SUPER INVERTER SERIES

MULTI TYPE
Service Manual 2018
 CONTENTS
1. General information of Indoor Units .......................... 1

2. Features ....................................................................... 2

3. Dimensions ................................................................ 12

4. Service Space (unit: mm) .......................................... 20

5. Wiring diagram .......................................................... 23

6. Static Pressure (Duct) ............................................... 30

7. Operation temperature range ................................... 31

8. Electronic function ...................................................... 32

9. General information of Outdoor Units ....................... 42

10. Features ........................................................................ 43

11. Dimensions................................................................... 44

12. Refrigeration Cycle Diagram ....................................... 45

13. Wiring diagram ............................................................. 47

14. Indoor units combination ............................................ 51

15 Sound Levels ............................................................. 53

16 Installation Details ..................................................... 54

17 Electronic control function ....................................... 62

18 Troubleshooting ........................................................ 67
※The specifications, designs, and information in this book are subject to change without notice for
product improvement.
1. General information of Indoor Units

Four-way cassette (compact) Silm cassette

Console 15C

A5 Ducted A6 Ducted

ODU

38QUS014DS2*
38QUS014DS2-2
38QUS018DS2*
38QUS018DS2-2 38QUS036DS4*
38QUS027DS3* 38QUS042DS5*

Model
Four-way
cassette Super slim cassette Console 15C A5 Duct A6 Duct ODU
(compact)
38QUS014DS2*
42QTD007D8S 42QTD024DS* 42QZA009DS* 42QHC007D8S 42QSS012DS* 42QSS007D8S
38QUS014DS2-2
38QUS018DS2*
42QTD009D8S 42QZA012DS* 42QHC009D8S 42QSS009D8S
38QUS018DS2-2
42QTD012D8S 42QZA018DS* 42QHC012D8S 42QSS012D8S 38QUS021DS3*
42QTD018D8S 42QHC018D8S 42QSS018DS* 38QUS027DS3*
42QHC024D8S 42QSS024DS* 38QUS028DS4*
38QUS036DS4*
38QUS042DS5*

*Model with gray Mark was phased.

1
2. Features
2.1 Four-way cassette type(compact)
⑴ New panel
 360°surrounding air outlet design, affords comfortable feeling

⑵ Compact design
 The body size is 570×260×570mm, it’s just smaller than the ceiling board, so it’s very easy for
installation and will not damage the decoration. The panel size is 647×50×647mm.
 The hooks are designed in the four corners of the body, which can save installation space.

⑶ Electric control box built-in design

 The E-box is simply and safely built inside the indoor unit. It’s convenient for installation and
maintenance. Can check the control part easily, you only need to open the air return grille.

⑷ Fresh air intake function:

 Fresh air fulfills air quality more healthy and comfortable.

2
 Fresh
Air

Dimension:Φ75mm

⑸ Air passage function

 Reserves the space for air outlet from the side of indoor unit; It’s availed to connect air duct
from the two sides to the nearby small rooms.

3
2.2 A5 Duct
⑴ Installation accessories: (Optional)
 Front Board, Canvas Air Passage, Filter, Panel, for easy installation

Front Board Filter Panel

⑵ Easy Installation: Two air inlet styles (Bottom side or Rear side)
 Air inlet from rear is standard for all capacity; air inlet from bottom is optional.
 The size of air inlet frame from rear and bottom is same, it’s very easy to move the cover from bottom to
rear side, or from rear to the bottom, in order to matching the installation condition.

Air intake from rear (Standard)

Air intake from bottom (Optional)

⑶ Fresh air intake function

 Install one duct from the reserved fresh-air intake to outdoor.
Continually inhale the fresh air to improve the quality of the indoor air, fulfills air quality more healthy and
comfortable.

⑷ Easy maintenance
 Clean the filter (Optional, standard product without filter)
It is easy to draw out the filter from the indoor unit for cleaning, even the filter is installed in rear side or
bottom side.

4
 Replace the motor or centrifugal fan
Remove the ventilated panel firstly. Remove a half of blower housing and take out the motor with
centrifugal fan. Directly remove two bolts, and then replace the motor or centrifugal fan easily.

Motor

Blower Housing

Ventilated Panel

⑸ Reserved remote on-off and central control ports

 Reserved remote on-off ports and central control ports, can connect the cable of an on-off controller or a
central controller to realize remote on-off control function or group control function.

5
 Remote on-off ports Central control ports

⑹ Built-in drain pump (Optional):

 Built-in drain pump can lift the water to 750mm upmost. It’s convenient to install drainage piping under
most space condition.

750mm upmost

⑺ Built-in display board

 The standard indoor unit can be controlled by wired controller.
 There is a display board with a receiver in the E-box. Move out the display, and fix it in other place, even
in the distance of 10m. The unit will realized remoter control.
 The wired controller and the display board can display the error code or production code when the chips
detect some failure.

6
 Wired Controller (Standard) Remote Controller (Optional)

Display

2.3 Console
(1) Consumes up to 30% less energy than non-inverter units
——DC inverter compressor
——indoor fan motor adopts DC motor

(2) Achieves set temperature more quickly

——air supplying from top and bottom or from top only
——air inlet from four directions

(3) Compact unit body, space saving

——this unit body is very thin and harmonious with room. It is beautiful, elegant and space saving.
——light weight and compact.

(4) Flexible installation.

——can be used for floor standing or lower wall applications
——as a floor standing floor model, it can be semi or fully recessed without loss of capacity.

(5) High efficiency filter

——built in Formaldehyde nemesis filter
——active-carbon and biological anti-virus filter is optional.

(6) Comfort
——flexible air blow: vertical auto swing and wide angle louvers ensure that warm air reaches the furthest
corners of the room and increase the air flow coverage
——Low noise operation, lowest to 23Db
——Low starting power and precise room temperature adjustment

(7) Powerful mode can be selected for rapid cooling or heating.

7
(8) Easy cleaning grille and maintenance

(9) Indoor unit adopts DC motor, it has five level fan speed meet different requirements.

7.4 Super slim cassette

(1) Overview
 Compact design, super slim body size, less space requiring in installation
 Each louver can be separately controlled, more comfort air blowing is possible.
 Auto-lifting panel design, more convenient to clean and maintain the filter. (optional)
(2) Fresh air intake function
 Fresh air fulfills air quality more healthy and comfortable.
 Ventilation motor is optional to increase the effect of fresh air.

(3) Optional ionizer generator

 Ionizer generator is optional to get refreshing air to your room.

Ionizer generator Ventilation motor

connector connector

 Ionizer can be switched on or off by remote controller.

When pressing the Clean Air button on the remote controller, Ionizer will work and the indicator light on
display board will shine.

8
(4) External air duct design
 Reserve external air duct, more flexible for the air supply.

(5) Built-in draining pump

 Due to the improvement of structure, more convenient to repair or replace the draining pump.

Draining Pump

 Built-in draining pump to make sure condensed water drain out reliably.

(6) Terminals for alarm lamp and long-distance on-off controller connection are standard
 Reserve terminals for the connection of alarm lamp and long-distance on-off controller, more human
control.

9
 Alarm lamp

Long-distance on-off controller

7.5 Ceiling-Floor
(1) New design, more modern and elegant appearance.

(2) Convenient installation

--The ceiling type can be easily installed into a corner of the ceiling even if the ceiling is very narrow
--It is especially useful when installation of an air conditioner in the center of the ceiling is impossible
due to a structure such as one lighting.

(3) Two direction auto swing (vertical & horizontal) and wide angle air flow,
--Air flow directional control minimizes the air resistance and produces wilder air flow to vertical
direction.
--The range of horizontal air discharge is widened which secures wider air flow distribution to provide
more comfortable air circulation no matter where the unit is set up

(4) New foam drain pan with plastic-spraying inner surface

10
(5) Easy operation.

(6) Remote control and optional wired control method.

11
3. Dimensions
3.1 Four-way cassette type (compact):

D r a in h o le
G a s s id e
L iq u id s id e ( fo r S e r v ic e )
Body

4 - in s ta ll h a n g e r

2- 1 5 0 D is tr ib u tio n d u c t

523

570
2- 170

E - p a r ts b o x

4 - S c r e w h o le
( fo r in s ta ll p a n e l)

545

570 260

3 2 D r a in p ip e
6 5 F r e s h a ir in ta k e

75
156
125
44

W ir in g c o n n e c tio n p o r t 40

68

Panel
647

647 50

12
3.2 A5 Duct

a i r i n l e t f r o m r e a r s i d e
A i r f i l t e r ( o p t i o n a l )

J
I

L B
H2 4 - i n s t a l l h a n g e r
A
H1 L i q u i d s i d e
W1
W2

2 5 D r a in p ip e G a s s i d e

M
2 5 D r a in p ip e
T e s t m o u th & T e s t c o v e r

C
2 5 D r a in c o n n e c tin g p ip e
( fo r p u m p )

E l e c t r i c c o n t r F
o r el s h abir oin ta
xke

E F
G
H

A i r f i l t e r ( o p t i o n a l )
K

a i r i n l e t f r o m b o t t o m s i d e

Note: standard product without filter Unit: mm

Size of install
Outline dimension(mm) Air outlet opening size Air return opening size Size of refrigerant pipe
Model hanger

A B C D E F G H I J K L M H1 H2 W1 W2

42QSS012DS* 700 210 635 570 65 493 35 119 595 200 80 740 350 120 143 95 150

13
3.3 Console

600
700 210

H a n g in g a r m
195

1 6 D r a in p ip e

14
3.4 Super-Slim Cassette Type
92 92

D
7 5 F r e s h a ir in ta k e

80
D
A 80

136
4 - in s ta ll h a n g e r
126
D 680
D Body
G a s s id e 91

90
L iq u id s id e

135
W ir in g c o n n e c tio n p o r t
92

92
E - p a r ts b o x
A

A
92

92
780
780

840
92

92
B
A

A
92

S e r v ic e h o le fo r

92
T e s t m o u th & T e s t c o v e r
d r a in in g p u m p 3 2 D r a in h o le

132
D
B 680 D
196
840
C

A A
D

B
D

92 92 92 92

Panel
950

950 55

Unit: mm
Model A B C D
42QTD024DS* 160 95 245 60

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3.5 Ceiling &Floor Type
2- 33 W ir in g c o n n e c t io n p o r t

2- 40 D r a in d is c h a r g e p o r t

204
140
94
120 F r e s h a ir in t a k e
R e f r ig e r a n t p ip e h o le
120

B
C

H a n g in g a r m
220
222

Capacity (KBtu/h) A B C D
18/24 1068 675 235 983

16
3.6 Ducted
A5

17
A6

18
3.7 Hi-wall
3.7.1 Indoor Unit

Model W D H
(KBtu/h)

42QHC007D8S
730 192 291
42QHC009D8S
42QHC012D8S 812 192 300
42QHC018D8S 973 218 319
42QHC024D8S 1082 225 338

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4. Service Space (unit: mm)
4.1 Four-way cassette (compact)

4.2 Duct
Ensure enough space required for installation and maintenance.

All the indoor units reserve the hole to joint the fresh air pipe. The hole size as following:

20
 Ne cessary roo m
Drain sid

A
>2500mm
out let intle t outlet

Chart 1 ground
No te:180 00-24000Btu/h(R 22) Series A ≥ 26 0mm
36000-48000Btu/h(R 22) Series A≥ 330mm

4.3 Console
Hook

Body
Nut

B
Ceiling 880mm
Panel
Chart 2
No te:180 00- 24000B tu/h(R 22) Seri es B= 240mm
360 00- 48000Btu /h(R 22) Series B= 310mm

4.4 Super-Slim Cassette Type

>1000mm

>1000m m
B
>1000m m

>1000mm

Chart 3

21
4.5 Ceiling &Floor Type

4.6 Hi-wall

22
5. Wiring diagram
38QUS014DS2*/ 38QUS014DS2-2/ 38QUS018DS2-2

38QUS018DS2*

23
38QUS021DS3*

38QUS027DS3*

24
38QUS028DS4*

38QUS036DS4*

25
38QUS042DS5*

42QHC007D8S、42QHC009D8S、42QHC012D8S、42QHC018D8S、42QHC024D8S

16022000A83297

26
42QTD007D8S/42QTD009D8S/42QTD012D8S/42QTD018D8S
42QTD009DS* 、42QTD012DS* 、42QTD018DS*

42QTD024DS*

27
42QSS012DS*

42QSS007D8S/42QSS009D8S/42QSS012D8S

28
42QSS018DS*, 42QSS024DS*

42QZA009DS*, 42QZA012D8S, 42QZA018DS*

29
6. Static Pressure (A5 Ducted)

30
7. Operation temperature range
Temperature
Cooling operation Heating operation Drying operation
Mode

Room temperature 18℃～32℃ 0℃～27℃ 18℃～32℃

Outdoor temperature 0℃～46℃ -15℃～24℃ 0℃～46℃

CAUTION:

1. If the air conditioner is used beyond the above conditions, certain safety protection features may
come into operation and cause the unit to operate abnormally.

2. The room relative humidity should be less than 80%. If the air conditioner operates beyond this figure,
the surface of the air conditioner may attract condensation. Please set the vertical air flow louver to its
maximum angle (vertically to the floor), and set HIGH fan mode.

3. The optimum performance will be achieved during this operating temperature zone.

31
8. Electronic function
Note: Below function only for light commercial, for Hi-wall units, please refer to 1 drive 1 service manuals.
8.1 Abbreviation
T1: Indoor room temperature

T2: Indoor evaporator temperature

T2B: Coil temperature of indoor heat exchanger outlet(This sensor is located in outdoor unit)

T3: Coil temperature of outdoor heat exchanger

T4: Outdoor ambient temperature

T5: Compressor discharge temperature

Ts: Setting temperature

8.2 Icon explanation on indoor display board

8.2.1 Four-way cassette (compact)

8.2.2 A5&A6 Duct

PRE-DEF indicator(cooling and heating type)
or fan only indicator(cooling only type)
Timer indicator Alarm indicator
Operation lamp Infrared signal receiver
Temporary button Display digital tube

MANUAL OPERATION TIMER DEF./FAN ALARM

8.2.3 Console

32
8.2.4 Super slim cassette

8.2.5 Ceiling& floor

8.2.6 15C

8.3 Main Protection

8.3.1 Three minutes delay at restart for compressor.
8.3.2 Sensor protection at open circuit and breaking disconnection.

8.3.3 Indoor fan delayed open function

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----When system starts up, the louver will be active immediately, and the indoor fan will open after certain
time.

----If the system runs in heating mode, the anti-cold wind function has priority.

8.3.4 Fan speed is out of control (For the units used DC fan motor)

For console:
When indoor fan speed keeps too low (300RPM) for certain time, the unit will stop and the LED will display
the failure.
For other models:

When indoor fan speed keeps too low (lower than 300 RPM) for 50s, the indoor fan will shut off and restart
30s later, if protection happened 3 times when fan motor restart continuously, the unit will stop and the LED
will display the failure.
8.3.5 Inverter module protection

The Inverter module has a protection function about current, voltage and temperature. If these protections
happen, the corresponding code will display on indoor unit and the unit will stop working.

8.4 Operation Modes and Functions

8.4.1 Fan-only mode
(1) Outdoor fan and compressor stop.

(2) For Console: Indoor fan can be set to high/med/low/breeze, for other models: Indoor fan can be set to
high/med/low/auto.

(3) The louver operates same as in cooling mode.

(4) Auto fan in fan-only mode acts as follow:

For all models:

T 1 -2 4

H
a (H -L )* 0 .7 5 + L

b (H -L )* 0 .5 + L

c (H -L )* 0 .2 5 + L

d L
e

8.4.2 Cooling mode

8.4.2.1 Outdoor fan running rules

34
 T4

A+

While A,B,C…means different fan speed of outdoor unit.

8.4.2.2 Indoor fan running rules

For all models:

In cooling mode, indoor fan runs all the time and the speed can be selected as high, medium, low and auto.
When the compressor is running, the indoor fan is controlled as below:
Setting fan
T1-Td ℃(°F) Actual fan speed
speed
H+(H+=H+G)
A H（=H）
H
B
H-（H-=H-G)
C
M+(M+=M+Z)
D M(M=M)
M
E
M-(M-=M-Z)
F
L+(L+=L+D)
G L(L=L)
L
H
L-(L-=L-D)
I

The auto fan acts as below rules:

T 1 -T d

H
a (H -L )* 0 .7 5 + L

b (H -L )* 0 .5 + L

c (H -L )* 0 .2 5 + L

d L
e

8.4.2.3 Evaporator low temperature T2 protection

For all models: When T2<4℃ for 250s or T2<0℃ , the indoor has no capacity demand and resume till
T2>8℃

35
8.4.3 Dry mode
8.4.3.1 Indoor fan speed is fixed at breeze and can’t be changed. The louver angle is the same as in cooling
mode.

8.4.3.2 Low indoor room temperature protection

In drying mode, if room temperature is lower than 10℃, the indoor fan will stop and not resume until room
temperature exceeds 12℃.

784.3.3 Evaporator anti-freezing protection and condenser high temperature protection are active and the
same as that in cooling mode.

8.4.3.4 The outdoor fan operates the same as in cooling mode.

8.4.4 Heating mode

8.4.4.1 Outdoor fan running rules

T4

A+

8.4.4.2 Indoor fan running rules

For all models:

In heating mode, indoor fan can be selected as high, medium, low and auto. The anti-cold- wind function has
the priority.
When the compressor is running, the indoor fan is controlled as below:
Setting fan
T1-Td℃ Actual fan speed
speed

H-（H-=H-G)
H
H（=H）
H+(H+=H+G)

M-(M-=M-Z)
M
M(M=M)
M+(M+=M+Z)

L-(L-=L-D)
L
L(L=L)
L+(L+=L+D)
-

If the compressor stops caused by the room temperature rising, the indoor fan will be forced to run 127

seconds with breeze. During this period, the anti-cold-wind is disabled.

36
Auto fan action in heating mode:

T 1 -T d

( H + - L ) * 0 .2 + L
( H + - L ) * 0 .4 + L

( H + - L ) * 0 .6 + L

( H + - L ) * 0 .6 + L

( H + - L ) * 0 .8 + L

H+

8.4.4.3 High evaporator coil temp.T2 protection:

If T2>63℃, the indoor unit has no capacity demand and resume till 48℃.

8.4.4.4 Prevent Over-Heating

In heating mode, when the indoor unit has no capacity requirement due to indoor room temperature
increased, the Indoor fan will run in super breeze. (Anti-cold wind function has the priority)

8.4.4.5 Defrosting mode：

Condition of defrosting:

AC will enter the defrosting mode according to the value of temp. of T3 and the value range of temp. change
of T3 and also the compressor running time.

Condition of ending defrosting:

If any one of the following items is satisfied, the defrosting will finish and the machine will turn to normal
heating mode.

----T3 rises to be higher than TCDE1℃.

----T3 keeps to be higher than TCDE2℃ for 80 seconds.

----The machine has run for 10 minutes in defrosting mode.

Defrosting action：

37
 4 -W a y v a lv e

n o lo n g e r th a n 1 0 m in
C o m p re s s o r
C o o l- F 9

T im e A 1 0 S
10S 30S
In d o o r fa n A n ti c o ld w in d

O u td o o r fa n

P M V r u n n in g
PMV 4 m in s w ith 4 8 0 P
480P

8.4.5 Auto-mode

This mode can be chosen by remote controller and the setting temperature can be changed between
17~30℃.
In auto mode, the machine will choose cooling, heating or fan-only mode according to the difference
between T1 and TS.
For all models:

T1-TS Running mode

T1-TS＞2℃ Cooling
-2< T1-TS≤2℃ Fan-only
T1-TS≤-2℃ Heating
Indoor fan will run at auto fan of the relevant mode.

The louver operates same as in relevant mode.

If the machine switches mode between heating and cooling, the compressor will keep stopping for 15
minutes and then choose mode according to T1-Ts.

If the setting temperature is modified, the machine will choose running function again.

8.4.6 Forced operation function

8.4.6.1 Enter forced operation function:

Press the touch button continually, the AC will run as below sequence:

Forced auto→Forced cooling→Off

When the machine is off, pressing the touch button will carry the machine to forced auto mode, after this, if
pressing the button once again, the machine will turn into forced cooling mode.

In forced cooling mode, pressing touch button will turn off the machine.
8.4.6.2 In forced operation mode, all general protections and remote control are available.

8.4.6.3 Operation rules:

38
Forced cooling mode:
The compressor runs at F2 frequency and indoor fan runs as breeze. After running for 30 minutes. the
machine will turn to auto mode as 24℃ setting temperature.

Forced auto mode:

The action of forced auto mode is the same as normal auto mode with 24℃ setting temperature.

8.4.6.4 When there’s indoor unit running in forced cooling, it is the master forced cooling unit. Other indoor
units will run at forced cooling mode too and they will be the slave forced cooling units. The slave forced
cooling units can not quit forced cooling mode until the master forced cooling unit quit, and turn to cooling
mode at low speed with 24℃ setting temperature.

7.4.6.5 The slave forced cooling units will not be controlled by other signals.

8.4.7 Timer Function

8.4.7.1 Timing range is 24 hours.

8.4.7.2 Timer on. The machine will turn on automatically when reaching the setting time.

8.4.7.3 Timer off. The machine will turn off automatically when reaching the setting time.
8.4.7.4 Timer on/off. The machine will turn on automatically when reaching the setting “on” time, and then
turn off automatically when reaching the setting “off” time.

8.4.7.5 Timer off/on. The machine will turn off automatically when reaching the setting “off” time, and then
turn on automatically when reaching the setting “on” time.

8.4.7.6 The timer function will not change the AC current operation mode. Suppose AC is off now, it will not
start up firstly after setting the “timer off” function. And when reaching the setting time, the timer LED will be
off and the AC running mode has not been changed.

8.4.7.7 The setting time is relative time.

8.4.8 Sleep mode

8.4.8.1 The sleep function is available in cooling, heating or auto mode.

8.4.8.2. Operation process in sleep mode is as follow.

After pressing ECONOMIC or SLEEP button on controller, the machine will turn into sleep mode.

When cooling, The set temperature rise 1℃ per hour(be lower than 30℃). Two hours later, the set
temperature will maintain as a constant and the fan speed is kept at low speed.

When heating, The set temperature decrease 1℃ per hour(be higher than 17℃). Two hours later, the set
temperature will maintain as a constant and the fan speed is kept at low speed (Anti-cold function takes
precedence over all).

When auto, After an hour running under economic mode ,if it is under cooling mode the set temp will rise 1℃,
if it is under heating mode the set temp will decrease 1℃, if it is under fan-only mode the set temp will be
changeless; the condition will be the same after the air conditioner running under economic mode after 2
hours, and during the next time the set temp do not change.

8.4.8.3 Operation time in sleep mode is 7 hours. After 7 hours the AC quits this mode and the AC will turn off.

39
8.4.8.4 Timer off and remote controller off signals have the priority compared with sleep function.

8.4.9 Auto-Restart function

The indoor unit is equipped with auto-restart function, which is carried out through an auto-restart module. In
case of a sudden power failure, the module memorizes the setting conditions before the power failure. The
unit will resume the previous operation setting (not including swing function) automatically after 3 minutes
when power returns.

If the memorization condition is forced cooling mode, the unit will run in cooling mode for 30 minutes and
turn to auto mode as 24℃ setting temp.

If AC is off before power off and AC is required to start up now, the compressor will have 1 minute delay
when power on. Other conditions, the compressor will have 3 minutes delay when restarts.

8.4.10 Drain pump control (For A5 Duct & Cassette)

Adopt the water-level switch to control the action of drain pump.

Main action under different condition :( every 5 seconds the system will check the water level one time)
1. When the A/C operates with cooling (including auto cooling) and forced cooling mode or dry mode, the
pump will start running immediately and continuously, till stop cooling or dry or no capacity demand.

2. Once the water level increase and up to the control point, LED will alarm and the drain pump open and
continue checking the water level. If the water level falls down below the control point (drain pump delay
close 1 minute) and operate with the last mode. Otherwise the entire system stop operating (including the
pump) and LED remain alarming after 3 minutes,

8.4.11 Follow me (optional)

1) If the indoor PCB receives the signal which results from pressing the FOLLOW ME button on remote
controller, the buzzer will emit a sound and this indicates the follow me function is initiated. But when the
indoor PCB receives signal which sent from remote controller every 3 minutes, the buzzer will not
respond. When the unit is running with follow-me function, the PCB will control the unit according to the
temperature from follow-me signal, and the temperature collection function of room temperature sensor
will be shielded, and the error detective function of room temperature sensor will be still invalid.
2) When the follow-me function is available, the PCB will not respond according to the setting temperature
from follow-me signal every 3 minutes.
3) The PCB will take action to the mode change information from remote controller signal, and the
follow-me function will be turned off. (if the wired remote controller does not initiate follow me function).
4) When the unit is running with follow-me function, if the PCB doesn’t receive any signal from remote
controller for 7 minutes or pressing FOLLOW ME button again, the follow-me function will be turned off
automatically, and the temperature collection function of room temperature sensor will be available, the
PCB will control the unit according to the room temperature detected from its own room temperature
sensor and setting temperature.
5) When the indoor PCB receives the follow-me signal from wired remote controller, the control is the

40
 same as that from wireless remote controller, but buzzer will not emit a sound. When the PCB receives
turning-off follow-me signal from wired remote controller, the unit will quit follow-me function at once.
The follow-me function controlled by wired remote controller prevails that by wireless remote controller.

8.4.12 Mode conflict

The indoor units can not work cooling mode and heating at same time.
Heating mode has a priority.
(1) Definition
Cooling mode Heating Mode Fan Off
Cooling mode No Yes No No
Heating Mode Yes No Yes No
Fan No Yes No No
Off No No No No
No: No mode conflict;

Yes: Mode conflict

(2) Unit action

 In case of one Indoor unit working in cooling mode or fan mode, and another indoor unit is set to heating
mode, the indoor unit working in cooling mode or fan mode will change to off. The outdoor unit will
change to heating mode after compressor stop 3 minutes. .
 In case of one Indoor unit working in heating mode, and another indoor unit is set to cooling mode or fan
mode, the indoor unit setting to cooling mode or fan mode will change to stand by. The outdoor unit will
continue working in heating mode.

If heating mode stops (not including the indoor unit in heating mode reaching the set temperature), 3
minutes after the outdoor unit restarts and works in cooling mode or fan-only mode.

41
9. General information of Outdoor Units
Model name Dimension (mm) Compressor

38QUS014DS2* 800x333x554 ASN108D22UEZ

38QUS014DS2-2 800x333x554 ASN140D21UFZ
38QUS018DS2* 845x363x702 ASM135D23UFZ
38QUS018DS2-2 800x333x554 ASM135D23UFZ
38QUS021DS3* 845x363x702 ASM135D23UFZ
38QUS027DS3* 845x363x702 ATF235D22UMT
38QUS028DS4* 946x410x810 ATF235D22UMT
38QUS036DS4* 946x410x810 ATF310D43UMT
38QUS042DS5* 946x410x810 ATF310D43UMT

42
10. Features

Outdoor unit

Power relay control

Low noise air flow system

Hydrophilic aluminum fin

The hydrophilic fin can improve the heating efficiency at operation mode.

4 way valve control

It is only operated in the heating operation mode except defrosting operation.

Anti-rust cabinet

Valve protection cover

It protects the valves and prevents water from dripping.

Discharge pipe temperature protection

43
11. Dimensions

Unit：mm
Model
W D H W1 A B
38QUS014DS2-2
800 333 554 860 514 340
38QUS018DS2-2
38QUS021DS3* 845 363 702 923 540 350
38QUS027DS3* 845 363 702 923 540 350
38QUS028DS4*
946 410 810 1034 673 403
38QUS036DS4*
38QUS042DS5* 946 410 810 1034 673 403

44
12. Refrigeration Cycle Diagram
12.1 Refrigeration circuit drawing of inverter 1 drive 2 type
IN D O O R OUTDOOR

E X V A C A P IL L A R Y A
L IQ U ID V A L V E A
CHECK VALVE

E X V B C A P IL L A R Y B
L IQ U ID V A L V E B T3
C ondenser
te m p . s e n s o r
C A P IL L A R Y T U B E

HEAT
EXCHANGE HEAT
T1 R oom T 4 A m b ie n t
(E V A P O R A T O R ) EXCHANGE
te m p . s e n s o r te m p . s e n s o r
(C O N D E N S E R )

T 2 B - A E v a p o r a to r
T 2 E v a p o r a to r G AS VALVE A te m p . s e n s o r o u tle t
te m p . s e n s o r
m id d le
4 -W A Y V A L V E
T 2 B -B
G AS VALVE B

A c c u m u la to r
T 5 D is c h a r g e
te m p . s e n s o r

C o m p re s s o r C O O L IN G

H E A T IN G

12.2 Refrigeration
IN D O circuit
OR drawing of inverter 1 drive 3 type OUTDOOR

E X V A C A P IL L A R Y A
L IQ U ID V A L V E A

E X V B C A P IL L A R Y B C H EC K VALVE
L IQ U ID V A L V E B

T3
E X V C C A P IL L A R Y C
L IQ U ID V A L V E C C ondenser
te m p . s e n s o r
C A P IL L A R Y T U B E

HEAT
EXCHANGE HEAT
T1 R oom T 4 A m b ie n t
(E V A P O R A T O R ) EXCHANGE
te m p . s e n s o r te m p . s e n s o r
(C O N D E N S E R )

T 2 B - A E v a p o r a to r
G AS VALVE A te m p . s e n s o r o u tle t
T 2 E v a p o r a to r
te m p . s e n s o r
m id d le T 2 B -B
G AS VALVE B
4 -W A Y V A L V E

T 2 B -C
G AS VALVE C
A c c u m u la to r T 5 D is c h a r g e
C O O L IN G
te m p . s e n s o r
C o m p re s s o r H E A T IN G

45
12.3 Refrigeration circuit drawing of inverter 1 drive 4 type
IN D O O R O UTDO OR

E X V A C A P ILLA R Y A
L IQ U ID V A L V E A

E X V B C A P ILLA R Y B
L IQ U ID V A L V E B
C H E C K V A LV E

E X V C C A P IL L A R Y C
L IQ U I D V A L V E C
T3
C ondenser
E X V D C A P IL L A R Y D te m p . s ens or
C A P ILLA R Y T U B E
L IQ U I D V A L V E D

HEAT
EXCHANGE HEAT
T 1 R oom T 4 A m b ie n t
(E V A P O R A T O R ) EXCHANGE
te m p . s ens or te m p . s ens or
(C O N D E N S E R )

T 2 B -A E v a p o ra to r
G A S V A LV E A t e m p . s e n s o r o u t le t

T 2 E v a p o ra to r
te m p . s ens or T 2 B -B
G A S V A LV E B
m id d le
4 -W A Y V A L V E
T 2 B -C A c c u m u la to r
G A S V A LV E C
H ig h p r e s s u re
s w itc h C O O LIN G
G A S V A LV E D T 2 B -D T 5 D is c h a rg e H E A T IN G
L o w p r e s s u re te m p . s ens or
s w itc h
C o m p re s s o r

12.4 Refrigeration circuit drawing of inverter 1 drive 5 type

IN D O O R OUTDOOR

E X V A C A P IL L A R Y A
L IQ U ID V A L V E A

E X V B C A P IL L A R Y B
L IQ U ID V A L V E B

E X V C C A P IL L A R Y C CHECK VALVE
L IQ U I D V A L V E C

T3
E X V D C A P IL L A R Y D
L IQ U I D V A L V E D C ondenser
te m p . s e n s o r
C A P IL L A R Y T U B E

E X V E C A P IL L A R Y E
L IQ U ID V A L V E E

HEAT
EXCHANGE HEAT
T1 Room T 4 A m b ie n t
(E V A P O R A T O R ) EXCHANGE
te m p . s e n s o r te m p . s e n s o r
(C O N D E N S E R )
T 2 B - A E v a p o ra to r
G AS VALVE A te m p . s e n s o r o u tle t

T 2 B -B
T 2 E v a p o r a to r G AS VALVE B
te m p . s e n s o r
m id d le T 2 B -C
G AS VALVE C
4 -W A Y V A L V E
A c c u m u la to r
C O O L IN G
G AS VALVE D T 2 B -D H ig h p r e s s u re
s w itc h H E A T IN G
T 5 D is c h a rg e
G AS VALVE E T 2 B -E L o w p r e s s u re te m p . s e n s o r
s w itc h
C o m p re s s o r

46
13. Wiring diagram
38QUS014DS2*/38QUS014DS2-2, 38QUS018DS2*/38QUS018DS2-2

47
Note: S(1)&S(2) are used in other type of models. They don't need to be connected in multi models.

38QUS021DS3*

48
38QUS027DS3*

38QUS036DS4*

49
38QUS042DS5*

50
14. Indoor units combination
14.1 Indoor unit combination for 38QUS014DS2-2
38QUS014DS2-2
One Unit Two Unit
7 7+7 9+9
9 7+9 9+12
12 7+12
18
14.2 Indoor unit combination for 38QUS018DS2*
38QUS018DS2-2
One Unit Two Unit
7 7+7 9+9
9 7+9 9+12
12 7+12 9+18
18 7+18 12+12
* means two indoor unit shall not operate simultaneously due to performance reduction.

14.3 Indoor unit combination for 38QUS021DS3*

38QUS021DS3-1
One Unit Two Unit Three Unit
7 7+7 9+9 7+7+7 9+9+9
9 7+9 9+12 7+7+9
12 7+12 9+18 7+7+12
18 7+18 12+12 7+9+9
14.4 Indoor unit combination for 38QUS027DS3*
38QUS027DS3-1
One Unit Two Unit Three Unit
7 7+7 9+9 12+18 7+7+7 7+9+9 9+9+9
9 7+9 9+12 7+7+9 7+9+12 9+9+12
12 7+12 9+18 7+7+12 7+9+18 9+12+12
18 7+18 12+12 7+7+18 7+12+12

51
14.5 Indoor unit combination for 38QUS028DS3*
38QUS028DS4-1
One Unit Two Unit Three Unit Four Unit
7 7+7 9+9 12+18 7+7+7 7+9+12 9+9+18 7+7+7+7 7+9+9+9
9 7+9 9+12 12+24 7+7+9 7+9+18 9+12+12 7+7+7+9 9+9+9+9
12 7+12 9+18 18+18 7+7+12 7+12+12 12+12+12 7+7+7+12
18 7+18 12+12 7+7+18 9+9+9 7+7+9+9
24 7+24 9+24 7+9+9 9+9+12 7+7+9+12
14.6 Indoor unit combination for 38QUS036DS4*
38QUS036DS4-1
One Unit Two Unit Three Unit Four Unit
7 7+7 9+9 12+18 7+7+7 7+9+9 7+12+18 9+9+18 9+18+18 7+7+7+7 7+7+9+9 7+7+12+18 7+9+12+18 9+9+12+12
9 7+9 9+12 12+24 7+7+9 7+9+12 7+12+24 9+9+24 12+12+12 7+7+7+9 7+7+9+12 7+9+9+9 7+12+12+12 9+12+12+12
12 7+12 9+18 18+18 7+7+12 7+9+18 7+18+18 9+12+12 12+12+18 7+7+7+12 7+7+9+18 7+9+9+12 9+9+9+9
18 7+18 9+24 7+7+18 7+9+24 9+9+9 9+12+18 7+7+7+18 7+7+9+24 7+9+9+18 9+9+9+12
24 7+24 12+12 7+7+24 7+12+12 9+9+12 9+12+24 7+7+7+24 7+7+12+12 7+9+12+12 9+9+9+18
14.7 Indoor unit combination for 38QUS042DS5*
38QUS042DS5-1
One Unit Two Unit Three Unit Four Unit Five Unit
7 7+7 9+9 12+18 7+7+7 7+9+9 7+12+18 9+9+18 9+18+18 7+7+7+7 7+7+9+9 7+7+12+18 7+9+9+18 7+9+18+18 9+9+9+12 9+9+12+24 7+7+7+7+7 7+7+7+9+9 7+7+9+9+9 7+9+9+9+9 7+9+12+12+12 9+9+12+12+12
9 7+9 9+12 12+24 7+7+9 7+9+12 7+12+24 9+9+24 12+12+12 7+7+7+9 7+7+9+12 7+7+12+24 7+9+9+24 7+12+12+12 9+9+9+18 9+12+12+12 7+7+7+7+9 7+7+7+9+12 7+7+9+9+12 7+9+9+9+12 9+9+9+9+9
12 7+12 9+18 18+18 7+7+12 7+9+18 7+18+18 9+12+12 12+12+18 7+7+7+12 7+7+9+18 7+7+18+18 7+9+12+12 7+12+12+18 9+9+9+24 9+12+12+18 7+7+7+7+12 7+7+7+9+18 7+7+9+9+18 7+9+9+9+18 9+9+9+9+12
18 7+18 9+24 7+7+18 7+9+24 9+9+9 9+12+18 12+12+24 7+7+7+18 7+7+9+24 7+9+9+9 7+9+12+18 7+12+12+24 9+9+12+12 12+12+12+12 7+7+7+7+18 7+7+7+9+24 7+7+9+12+18 7+9+9+12+12 9+9+9+9+18
24 7+24 12+12 7+7+24 7+12+12 9+9+12 9+12+24 12+18+18 7+7+7+24 7+7+12+12 7+9+9+12 7+9+12+24 9+9+9+9 9+9+12+18 12+12+12+18 7+7+7+7+24 7+7+7+12+18 7+7+12+12+12 7+9+9+12+18 9+9+9+12+12

52
15 Sound Levels
Outdoor Unit

Microphone

1.0m
Note: H= 0.5 × height of outdoor unit

Model Noise Power dB(A) Noise level dB(A)

38QUS014DS2* 63 56
38QUS014DS2-2 64 56
38QUS018DS2* 66 59.5
38QUS018DS2-2 65 57
38QUS021DS3* 66 58
38QUS027DS3* 68 61
38QUS028DS4* 67 61
38QUS036DS4* 68 63
38QUS042DS5* 68 63

53
16 Installation Details
16.1.1 Wrench torque sheet for installation
Outside diameter Torque Additional tightening torque
mm N.cm N.cm
Ф6.35 1500(153kgf.cm) 1600(163kgf.cm)
Ф9.52 2500(255kgf.cm) 2600(265kgf.cm)
Ф12.7 3500(357kgf.cm) 3600(367kgf.cm)

16.1.2 Connecting the cables

The power cord of connect should be selected according to the following specifications sheet.

Rated current of appliance Nominal cross-sectional area (mm²)

>3 and ≤6 0.75
>6 and ≤10 1
>10 and ≤16 1.5
>16 and ≤25 2.5
The cable size and the current of the fuse or switch are determined by the maximum current indicated on the
nameplate which located on the side panel of the unit. Please refer to the nameplate before selecting the
cable, fuse and switch.

16.1.3 Pipe length and the elevation

Maximum piping length and height difference

1 drive 2 1 drive 3 1 drive 4 1 drive 5

Max. length for all rooms (m) 30 45 60 75

Max. length for one IU (m) 25 30 35 35

Max. height difference between IU and OU (m) 15 15 15 15

Max. height difference between IUs (m) 10 10 10 10

Additional refrigerant charge

1 drive 2 1 drive 3 1 drive 4 1 drive 5

Chargeless pipe
15 22.5 30 37.5
length (m)

Additional
15 x (length for all 15 x (length for all 15 x (length for all 15 x (length for all
refrigerant charge
rooms - 15) rooms – 22.5) rooms - 30) rooms – 37.5)
(g)

Caution:

● Refrigerant pipe diameter is different according to indoor unit to be connected. When using the
extension pipe, refer to the tables below.

54
● When refrigerant pipe diameter is different from that of outdoor unit union (for 18K&24K indoor unit),
additional transfer connector needs to be used on outdoor unit union.

Indoor unit Extension pipe diameter (mm/inch)

Model Pipe diameter (mm/inch)

Liquid 6.35(1/4) Liquid 6.35(1/4)

7K9K12K
Gas 9.52(3/8) Gas 9.52(3/8)

Liquid 6.35(1/4) Liquid 6.35(1/4)

18K
Gas 12.7(1/2) Gas 12.7(1/2)

24K Liquid 9.52(3/8) Liquid 9.52(3/8)

Gas 15.9(5/8) Gas 15.9(5/8)

Outdoor unit union diameter (mm/inch)

Liquid 6.35(1/4)

Indoor unit A/B/C/D/E 9.52(3/8)

Gas
12.7(1/2)

16.1.4 Installation for the first time

Air and moisture in the refrigerant system have undesirable effects as below:
● Pressure in the system rises.
● Operating current rises.
● Cooling or heating efficiency drops.
● Moisture in the refrigerant circuit may freeze and block capillary tubing.
● Water may lead to corrosion of parts in the refrigerant system.
Therefore, the indoor units and the pipes between indoor and outdoor units must be leak tested and
evacuated to remove gas and moisture from the system.
Gas leak check (Soap water method):
Apply soap water or a liquid neutral detergent on the indoor unit connections or outdoor unit
connections by a soft brush to check for leakage of the connecting points of the piping. If bubbles come out,
the pipes have leakage.
1. Air purging with vacuum pump

55
 (Indoor unit) (Liquid side) (Outdoor unit)

Two-way valve

Close

(Gas side)

Three-way valve

Manifold valve Close

Compound meter
Pressure
gauge
-0.1MPa
Lo Hi

Handle Lo Handle Hi
Charge hose Charge hose

Vacuum
pump

Vacuum
pump

1) Completely tighten the flare nuts of the indoor and outdoor units, confirm that both the 2-way and 3-way
valves are set to the closed position.
2) Connect the charge hose with the push pin of handle lo to the 3-way valves gas service port..
3) Connect the charge hose of handle hi connection to the vacuum pump.
4) Fully open the handle Lo of the manifold valve.
5) Operate the vacuum pump to evacuate.
6) Make evacuation for 30 minutes and check whether the compound meter indicates -0.1Mpa. If
the meter does not indicate -0.1Mpa after pumping 30 minutes, it should be pumped 20 minutes more. If the
pressure can’t achieve -0.1Mpa after pumping 50 minutes, please check if there are some leakage points.
Fully close the handle Lo valve of the manifold valve and stop the operation of the vacuum pump. Confirm
that the gauge needle does not move (approximately 5 minutes after turning off the vacuum pump).
7) Turn the flare nut of the 3-way valves about 45°counterclockwise for 6 or 7seconds after the gas
coming out, then tighten the flare nut again. Make sure the pressure display in the pressure indicator is a
little higher than the atmosphere pressure. Then remove the charge hose from the 3 way valve.
8) Fully open the 2 way valve and 3 way valve and securely tighten the cap of the 3 way valve.

56
2. Adding the refrigerant if the pipe length >5m

Electronic scale

Procedure:
1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve.

Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of the
cylinder. If the refrigerant is R410A, make the cylinder bottom up to ensure the liquid charge.

2). Purge the air from the charge hose.

Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air (be
careful of the liquid refrigerant).

3) Put the charging cylinder onto the electronic scale and record the weight.

4) Operate the air conditioner at the cooling mode.

5) Open the valves (Low side) on the charge set and charge the system with liquid refrigerant.
6).When the electronic scale displays the proper weight (refer to the table), disconnect the charge hose from
the 3-way valve’s service port immediately and turn off the air conditioner before disconnecting the hose.
7). Mount the valve stem caps and the service port

Use torque wrench to tighten the service port cap to a torque of 18N.m.

Be sure to check for gas leakage.

57
16.1.5 Adding the refrigerant after running the system for many years

Electronic scale

Procedure:

1). Connect the charge hose to the 3-way service port, open the 2-way valve and the 3-way valve.
Connect the charge hose to the valve at the bottom of the cylinder. If the refrigerant is R410A, make the
cylinder bottom up to ensure liquid charge.

2). Purge the air from the charge hose.

Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air (be
careful of the liquid refrigerant).

3) Put the charging cylinder onto the electronic scale and record the weight.

4) Operate the air conditioner at the cooling mode.

5) Open the valves (Low side) on the charge set and charge the system with liquid refrigerant.
6).When the electronic scale displays the proper weight (refer to the gauge and the pressure of the low side),
disconnect the charge hose from the 3-way valve’s service port immediately and turn off the air conditioner
before disconnecting the hose.
7). Mount the valve stem caps and the service port

Use torque wrench to tighten the service port cap to a torque of 18N.m.

Be sure to check for gas leakage.

58
16.1.6 Re-installation while the indoor unit need to be repaired
1. Collecting the refrigerant into the outdoor unit

Procedure

1). Confirm that both the 2-way and 3-way valves are set to the opened position
Remove the valve stem caps and confirm that the valve stems are in the opened position.
Be sure to use a hexagonal wrench to operate the valve stems.
2). Connect the charge hose with the push pin of handle lo to the 3-way valves gas service port.
3). Air purging of the charge hose.
Open the handle Lo valve of the manifold valve slightly to purge air from the charge hose for 5 seconds and
then close it quickly.
4). Set the 2-way valve to the close position.
5). Operate the air conditioner at the cooling cycle and stop it when the gauge indicates 0.1MPa.
6). Set the 3-way valve to the closed position immediately
Do this quickly so that the gauge ends up indicating 0.3 to 0.5Mpa.
Disconnect the charge set, and tighten the 2-way and 3-way valve’s stem nuts.
Use a torque wrench to tighten the 3-way valves service port cap to a torque of 1.8 kgf.m.
Be sure to check for gas leakage.

59
16.1.7 Re-installation while the outdoor unit need to be repaired
1. Evacuation for the whole system

Procedure:

1). Confirm that both the 2-way and 3-way valves are set to the opened position.
2). Connect the vacuum pump to 3-way valve’s service port.
3). Evacuation for approximately one hour. Confirm that the compound meter indicates -0.1Mpa.
4). Close the valve (Low side) on the charge set, turn off the vacuum pump, and confirm that the gauge
needle does not move (approximately 5 minutes after turning off the vacuum pump).
5). Disconnect the charge hose from the vacuum pump.

60
2. Refrigerant charging

Procedure:
1). Connect the charge hose to the charging cylinder, open the 2-way valve and the 3-way valve
Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of the
cylinder. If the refrigerant is R410A, make the cylinder bottom up to ensure liquid charge.

2). Purge the air from the charge hose

Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air (be
careful of the liquid refrigerant).

3) Put the charging cylinder onto the electronic scale and record the weight.
4). Open the valves (Low side) on the charge set and charge the system with liquid refrigerant
If the system cannot be charge with the specified amount of refrigerant, or can be charged with a little at a
time (approximately 150g each time) , operating the air conditioner in the cooling cycle; however, one time is
not sufficient, wait approximately 1 minute and then repeat the procedure.
5).When the electronic scale displays the proper weight, disconnect the charge hose from the 3-way valve’s
service port immediately

If the system has been charged with liquid refrigerant while operating the air conditioner, turn off the air
conditioner before disconnecting the hose.

6). Mounted the valve stem caps and the service port

Use torque wrench to tighten the service port cap to a torque of 18N.m.

Be sure to check for gas leakage

61
17 Electronic control function
17.1 Abbreviation
T1: Indoor ambient temperature
T2: Coil temperature of indoor heat exchanger middle.

T2B: Coil temperature of indoor heat exchanger outlet(This sensor is located in outdoor unit)
T3: Coil temperature of outdoor heat exchanger

T4: Outdoor ambient temperature

T5: Compressor discharge temperature

Ts: Setting temperature

17.2 Electric control working environment.

17.2.1 Input voltage: 198V~264V.
17.2.2 Input power frequency:50Hz.
17.2.3 Indoor fan normal working amp. is less than 1A.
17.2.4 Outdoor fan. normal working amp. is less than 1.5A.
17.2.5 Four-way valve normal working amp. is less than 1A.

17.3 Outdoor unit’s digital display tube

There is a digital display tube in outdoor PCB.
Digital display tube display function
 In standby , the LED displays “- -”
 In compressor operation, the LED display the running frequency,
 In defrosting mode, The LED displays “dF” or alternative displays between running frequency and
“dF”(each displays 0.5s)
 In compressor pre-heating, The LED displays “PH” or alternative displays between running frequency
and “PH”(each displays 0.5s)
 During the oil return process, The LED displays “RO” or alternative displays between running
frequency and “RO”(each displays 0.5s)
 In low ambient cooling mode, the LED displays “LC” or alternative displays between running
frequency and “LC”(each displays 0.5s)
 In forced cooling mode, the LED displays “FC” or alternative displays between running frequency and
“FC”(each displays 0.5s)
 When PFC module protection occurs three times within 15 minutes, the LED displays “E6” or
alternative displays between running frequency and “E6”(each displays 0.5s)
 In protection or malfunction, the LED displays error code or protection code.

62
17.4 Outdoor unit point check function
There is a check switch in outdoor PCB.
Press the switch N times it will display the content corresponding to No. N. After getting into the check
function, it will display No. N with 1.5s, meanwhile the low bit decimal of digit display flashing, indicated to
get into the check function display. After 1.5s, it will display the content corresponding to No. N.
the digital display tube will display the follow procedure when push SW1 each time.
Display Remark
0 Normal display Display running frequency, running state or malfunction code
1 No. of indoor units in good connection Actual data
2 Outdoor unit running mode code Standby:0,Fan only 1, Cooling:2, Heating:3, Forced cooling:4 Forced
defrosting:5
3 A indoor unit capacity
4 B indoor unit capacity
The capacity unit is horse power. If the indoor unit is not connected,
5 C indoor unit capacity the digital display tube will show: “――”
6 D indoor unit capacity (7K:0.8HP, 9K:1HP,12K:1.2HP,18K:1.5HP)

7 E indoor unit capacity

8 A Indoor unit capacity demand code
9 B Indoor unit capacity demand code
Norm value*HP
10 C Indoor unit capacity demand code
(7K:0.8HP, 9K:1HP,12K:1.2HP,18K:1.5HP)
11 D Indoor unit capacity demand code
12 E Indoor unit capacity demand code
13 Total indoor units amendatory capacity
demand code
14 The frequency corresponding to the total
indoor units amendatory capacity demand
15 The frequency after the frequency limit
16 The frequency sending to compressor
control chip
17 A indoor unit evaporator outlet temp.(T2BA)
18 B indoor unit evaporator outlet temp.(T2BB) If the temp. is lower than -9 degree, the digital display tube will show
19 C indoor unit evaporator outlet temp.(T2BC) “-9”.If the temp. is higher than 70 degree, the digital display tube will
show “70”. If the indoor unit is not connected, the digital display tube
20 D indoor unit evaporator outlet temp.(T2BD) will show: “――”
21 E indoor unit evaporator outlet temp.(T2BE)
22 A indoor unit room temp.(T1A) If the temp. is lower than 0 degree, the digital display tube will show
“0”.If the temp. is higher than 70 degree, the digital display tube will
23 B indoor unit room temp.(T1B)
show “70”. If the indoor unit is not connected, the digital display tube
24 C indoor unit room temp.(T1C) will show: “――”
25 D indoor unit room temp.(T1D)
26 E indoor unit room temp.(T1E)
27 A indoor unit evaporator temp.(T2A)
28 B indoor unit evaporator temp.(T2B)
29 C indoor unit evaporator temp.(T2C) If the temp. is lower than -9 degree, the digital display tube will show
30 D indoor unit evaporator temp.(T2D) “-9”.If the temp. is higher than 70 degree, the digital display tube will
show “70”. If the indoor unit is not connected, the digital display tube
31 E indoor unit evaporator temp.(T2E) will show: “――”
32 Condenser pipe temp.(T3)
33 Outdoor ambient temp.(T4)
34 Compressor discharge temp.(T5) The display value is between 30~129 degree. If the temp. is lower
than 30 degree, the digital display tube will show “30”.If the temp. is
higher than 99 degree, the digital display tube will show single digit
and tens digit. For example, the digital display tube show “0.5”,it
means the compressor discharge temp. is 105 degree.)
35 AD value of current The display value is hex number.

63
 36 AD value of voltage For example ,the digital display tube show “Cd”, it means AD value is
205.
37 EXV open angle for A indoor unit
Actual data/4.
38 EXV open angle for B indoor unit
If the value is higher than 99, the digital display tube will show single
39 EXV open angle for C indoor unit digit and tens digit.
40 EXV open angle for D indoor unit For example ,the digital display tube show “2.0”,it means the EXV
open angle is 120×4=480p.)
41 EXV open angle for E indoor unit
Frequency limit caused by IGBT
Bit7 The display value
radiator
is hex number. For
Bit6 Frequency limit caused by PFC example, the
Bit5 Frequency limit caused by T4. digital display tube
show 2A,then
42 Frequency limit symbol Bit4 Frequency limit caused by T2. Bit5=1, Bit3=1,
Bit3 Frequency limit caused by T3. Bit1=1.
It means
Bit2 Frequency limit caused by T5.
frequency limit
Bit1 Frequency limit caused by current caused by T4,T3
and current.
Bit0 Frequency limit caused by voltage
43 Average value of T2 (Sum T2 value of all indoor units)/( number of indoor units in good
connection)(cooling:T2B, heating:T2)
44 Outdoor unit fan motor state Fan off:0, High speed:1, Med speed:2, Low speed:3 Breeze:4, Super
breeze:5
45 The last error or protection code 00 means no malfunction and protection

17.5 Protection
17.5.1 Three minutes delay at restart for compressor.
17.5.2 Temperature protection of compressor discharge.
When the compressor discharge temp. is getting higher, the running frequency will be limited as below rules:

T5

C o m p re s s o r o ff

F r e q u e n c y lim it

F r e q u e n c y h o l d in g

N o rm a l

17.5.3 Low voltage protection

VO LTAGE

N o li m it

VO LT_LTM _FR EQ 1_AD D

VO LT_LTM _FR EQ 2_AD D

Note: if the low voltage protection occurs and not resumes within 3min, it will keep the protection always
after restart the machine.

64
17.5.4 Compressor current limit protection
Temperature interval.of current limit is same as range of T4 limited frequency.
Cooling mode:
T4

C o o lZ o n e 5

C o o lZ o n e 4

C o o lZ o n e 3

C o o lZ o n e 2

C o o lZ o n e 1

Heating mode:
T4

H e a tZ o n e 4

H e a tZ o n e 3

H e a tZ o n e 2

H e a tZ o n e 1

17.5.5 Indoor / outdoor units communication protection

If the indoor units cannot receive the feedback signal from the outdoor units for 2 minutes, the AC will stop
and display the failure.

17.5.6 High condenser coil temp. protection.

T3

O ff

D e c re a s e

H o ld

R esum e

17.5.7 Outdoor unit anti-freezing protection

When T2<4℃ for 250 seconds or T2<0℃, the indoor unit capacity demand will be zero and resume to
normal when T2>8℃ and the time of protection is no less than 3 minutes.

17.5.8 Oil return

Running rules:
1. If the compressor frequency keeps lower than setting frequency for setting time, the AC will rise the
frequency to setting frequency for setting time and then resume to former frequency.
2. The EXV will keep 300p while the indoor units will keep the current running mode.

65
If the outdoor ambient is higher than setting frequency during the oil return, the AC quit oil return.

17.5.9 Low outdoor ambient temperature protection

When compressor is off, T4 is be lower than -35℃.for 10s, the AC will stop and display “LP”.
When compressor is on, T4 is be lower than -40℃.for 10s, the AC will stop and display “LP”.
When T4 is no lower than -32℃.for 10s, the unit will exit protection.

66
18 Troubleshooting
18.1 Indoor unit error code explanation:
For Console
Operation Lamp
Malfunction Timer Lamp
(flashes)
Indoor EEPROM malfunction X 1
Communication malfunction between indoor and outdoor units X 2
Indoor fan speed has been out of control X 4
Open or short circuit of T1 temperature sensor X 5
Open or short circuit of T2 temperature sensor X 6
Overcurrent protection (For some units) O 1
Open or short circuit of T4 temperature sensor O 2
Open or short circuit of T3 temperature sensor O 3
Open or short circuit of T5 temperature sensor O 4
Outdoor EEPROM malfunction (For some units) O 5
Outdoor fan speed is out of control O 6
Open or short circuit of T2B temperature sensor (For free-match indoor units) O 7
IPM module malfunction ☆ 1

Over voltage or over low voltage protection ☆ 2

Too low ambient temperature protection ☆ 4

Inverter compressor drive protection ☆ 5

Mode conflict ☆ 6

Low pressure protection of compressor ☆ 7

O (on) X(off) ☆(flash at 2Hz)

For other type

Operation Lamp
Malfunction Error Code Timer Lamp
(flashes)
Indoor EEPROM malfunction E0 X 1
Communication malfunction between indoor and outdoor units E1 X 2
Indoor fan speed has been out of control E3 X 4
Open or short circuit of T1 temperature sensor E4 X 5
Open or short circuit of T2 temperature sensor E5 X 6
Water level alarm EE X 8
Overcurrent protection (For some units) F0 O 1
Open or short circuit of T4 temperature sensor F1 O 2
Open or short circuit of T3 temperature sensor F2 O 3
Open or short circuit of T5 temperature sensor F3 O 4
Outdoor EEPROM malfunction (For some units) F4 O 5
Outdoor fan speed is out of control F5 O 6
Open or short circuit of T2B temperature sensor (For free-match indoor
F6 O 7
units)

Communication error between auto-lifting panel and slim cassette (For F7 O 8

67
slim cassette with auto-lifting panel)
Auto-lifting panel is faulty (For slim cassette with auto-lifting panel) F8 O 9
Auto-lifting panel is not closed (For slim cassette with auto-lifting panel) F9 O 10
IPM module malfunction P0 ☆ 1

Over voltage or over low voltage protection P1 ☆ 2

Too low ambient temperature protection P3 ☆ 4

Error rotor position protection of compressor P4 ☆ 5

Mode conflict P5 ☆ 6

Low pressure protection of compressor P6 ☆ 7

O (on) X(off) ☆(flash at 2Hz)

18.2 Outdoor unit error code explanation:

Display LED STATUS

E0 Outdoor EEPROM malfunction

E2 Indoor / outdoor units communication error

E3 Communication malfunction between IPM board and outdoor main board

E4 Open or short circuit of outdoor unit temperature sensor

E5 Voltage protection

E8 Outdoor fan speed has been out of control

F1 No A Indoor unit coil outlet temperature sensor or connector of sensor is defective

F2 No B Indoor unit coil outlet temperature sensor or connector of sensor is defective

F3 No C Indoor unit coil outlet temperature sensor or connector of sensor is defective

F4 No D Indoor unit coil outlet temperature sensor or connector of sensor is defective

F5 No E Indoor unit coil outlet temperature sensor or connector of sensor is defective

P1 High pressure protection (ForM4OE-28HFN1-Q, 38QUS036DS4*, 38QUS042DS5*)

P2 Low pressure protection (ForM4OE-28HFN1-Q, 38QUS036DS4*, 38QUS042DS5*)

P3 Current protection of compressor

P4 Temperature protection of compressor discharge

P5 High temperature protection of condenser

P6 IPM module protection

LP Low ambient temperature protection

Note: Once these error codes display, they will disappear in at least 30 seconds if the unit come back to
normal.(Except E2&E3)

68
18.3 Trouble shooting
18.3.1 For the indoor unit
18.3.1.1 Indoor EEPROM malfunction

Power off, then restart the

unit 2 minutes later

Yes

Replace the indoor main PCB

EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and
reprogrammed using a pulsed voltage.

69
18.3.1.2 Indoor / outdoor units communication error
Indoor / outdoor units communication error

Start: Power off , then Power on the

A/C by the Breaker. (reconnect the
power wire). Is it still displaying the
error code?

Yes

Check wiring on the outdoor and indoor

terminal follow the wiring diagram. Is all No Reconnect the wiring
connecting correctly?
No
No
Reconnect the wiring

Yes

Measure Vs, is it moving

Turn on all indoor unit by remote
alternately between positive value A: Is all the wiring between
No and negative value? (Vs is the No terminal and Indoor PCB
controller. Is all indoor unit display
voltage between S and N). Refer connect ok?
PIC 1

Yes Yes
Yes
Yes
Replace the Indoor PCB

Turn off the all indoor units. Is IPM Replace IPM board or
power LED or operating LED lamp No the outdoor main PCB
On? Refer PIC2

Power on by remote
controller, IIs it still
Yes displaying the error code
after 3 minutes?

Is main board“ ” Is the reactor connecting

No No Reconnect the wiring
lamp on? Refer PIC 3. well？

No

Yes Yes

Replace the outdoor main PCB

Is indoor units number correct? Check

on the outdoor check point . (2 for dual
Trouble is solved
zone, 3 for tri zone, 4 for qua zone,5 for
qui zone). Refer PIC 4.

No first time No second time A

Replacee outdoor unit PCB assembly(include

wiring) totally

70
 Pic 1: check the voltage of N to S
(Vs), is it moving alternately
between positive value and negative
value?

Pic 2: IPM or outdoor main PCB

Operating

Self-Check

Pic 2: IPM or outdoor main PCB

Power,

Self-Check

els) Operating

71
 PIC3 : Main board LED when power on and unit
standby.

. PIC 4: check point button,

Press 1 time for check how many indoor units are
connected

72
18.3.1.3 indoor unit fan speed has been out of control

Power
Power off,
off, then
then restart
restart the
the
unit
unit 2 minutes later. IsIs itit still
2 minutes later. still No The
The unit
unit operates
operates normally.
normally.
displaying
displaying the
the error
error code?
code?

Yes
Find
Find out
out the
the cause
cause and
and
Shut
Shut offoff the
the power
power supply,
supply, have it solved.
have it solved. For
For
rotate
rotate the
the fan
fan by
by hand.
hand. Does
Does No example,
example, whether
whether the
the fan
fan
itit rotate isis blocked
blocked oror the
the screws
screws
rotate properly?
properly?
which
which fix
fix the
the fan
fan are
are
tighten.
tighten.
Yes

Check
Check the
the wiring
wiring ofof fan
fan
motor.
motor. Are
Are all
all the
the No Correct
Correct the
the connections.
connections.
connections
connections good?
good?

Yes

Check
Check whether
whether the
the main
main PCB
PCB No Replace
Replace the
the main
main PCB
PCB
isis normal
normal through
through index
index 1?
1?

Yes

Replace
Replace the
the fan
fan motor
motor No

Index 1:
1: Indoor AC fan motor
Power on and set the unit running in fan mode at high fan speed. After running for 15 seconds, measure the
voltage of pin1 and pin2. If the value of the voltage is less than 100V(208~240V power supply)or 50V(115V
power supply), the PCB must have problems and need to be replaced.

2. Indoor DC fan motor(control chip is inside fan motor)

Power on and when the unit is in standby, measure the voltage of pin1-pin3, pin4-pin3 in fan motor
connector. If the value of the voltage is not in the range showing in below table, the PCB must have
problems and need to be replaced.
For other models:

73
For console:
5
4
6

1 3

DC motor voltage input and output

For split type:
NO. Color Signal Voltage
1 Red Vs/Vm 280V~380V
2 --- --- ---
3 Black GND 0V
4 White Vcc 14-17.5V
5 Yellow Vsp 0~5.6V
6 Blue FG 14-17.5V

For other types:

NO. Color Signal Voltage
1 Red Vs/Vm 192V~380V
2 --- --- ---
3 Black GND 0V
4 White Vcc 13.5-16.5V
5 Yellow Vsp 0~6.5V
6 Blue FG 13.5-16.5V

74
18.3.1.4 Open or short circuit of temperature sensor.

Check
Check the
the connections
connections
between
between temperature
temperature No Correct
Correct the
the connections.
connections.
sensor
sensor and
and PCB.
PCB. Are
Are the
the
connections good?
connections good?

Yes

Measure
Measure the
the resistance
resistance value
value
of
of the
the sensor
sensor via
via Appendix
Appendix 11

IsIs itit normal?

normal? No Replace
Replace the
the sensor.
sensor.

Yes

Replace
Replace the
the indoor
indoor PCB
PCB

18.3.1.5 Full-water malfunction

Power
Power off,off, then
then restart
restart the
the unit
unit 22 minutes
minutes
later.
later. Is
Is itit still
still displaying
displaying the
the error
error code?
code?

Yes

IfIf the
the water-level
water-level switch
switch No Insert
Insert the
the water-level
water-level switch
switch well
well
is
is inserted
inserted well?
well?

Yes

IfIf the
the water-level
water-level switch
switch Yes Replace
Replace the
the water-level
water-level switch
switch
is
is broken?
broken?

No

Replace
Replace the
the water
water pump,
pump, IfIf
malfunction
malfunction isis still
still not
not
solved
solved

Yes

Replace
Replace the
the indoor
indoor main
main PCB
PCB

75
18.3.2 For the super-slim cassette with up-down panel
18.3.2.1 Communication error between indoor unit and up-down panel
F0
F0 Displayed
Displayed
F7

Communication
Communication failure
failure between
between
indoor unit and up-down
indoor unit and up-down panel
panel

Check
Check the
the wire
wire connection
connection
between
between up-down
up-down panel panel and
and No Correct
Correct the
the connection
connection
indoor
indoor unit,
unit, isis itit right?
right?

Yes

Replace
Replace the
the up-down
up-down panel
panel No Replace
Replace the
the indoor
indoor main
main PCB
PCB

18.3.2.2 Up-down panel is defective

F1
F1 Displayed
F8 Displayed

Up-down
Up-down panel
panel is
is defective
defective

IfIf panel
panel can
can not
not move
move Retry
Retry ifif panel
panel can
can up
up and
and
slightly, check
slightly, check thethe wiring
wiring No
down
down normally?
normally?
of
of louver
louver motors
motors

No No

IfIf panel
panel can
can move move slightly,
slightly, power
power
off, then restart
off, then restart the unitthe unit 22 minutes
minutes
later.
later. IfIf the
the error
error still
still exists?
exists?
Yes
Reconnect
Reconnect
No

Replace
Replace the
the louver
louver Check
Check the
the wiring
wiring of
of No Reconnect
Reconnect
motors
motors left
left and
and right
right sensors
sensors

Yes

The
The up-down
up-down panel
panel isis defective.
defective. No
No
replace
replace itit

76
18.3.3 For the outdoor unit
18.3.3.1 Outdoor EEPROM malfunction(ODU E0)

Power
Power off,
off, then
then restart
restart the
the
unit
unit 22 minutes
minutes later
later

Yes

Replace
Replace the
the outdoor
outdoor main
main PCB
PCB

EEPROM: An electrically erasable programmable read-only memory whose contents can be erased and
reprogrammed using a pulsed voltage.

77
18.3.3.2 Communication malfunction between IPM board and outdoor main board(ODU E3)

E3 display

Communication malfunction between

IPM board and outdoor main board

Is there at least one LED in

the IPM board light?

No

Check the signal wire between

the IPM board and the main Yes
board, is it connected good?

No

Yes
Reconnect and retry. Is
error still display?

No

No
Replace IPM board, and
then check whether the Yes
system can run normally

No

Replace outdoor main

board, and then check
Yes
whether the system can run
normally

No

Replace the electric control

Trouble is solved
box

78
18.3.3.3 Voltage protection(ODU E5)

Voltage protection

Check the voltage of

outdoor unit power supply,
whether the voltage No Check the power supply
between L(L1) and N (L2) is
about 220~240VAC

Yes

Check whether the voltage

of IPM board P and N is
normal? DC277-356V for
18-27KBtu/h; DC277-410V
for 36-42KBtu/h

No

Replace bridge rectifiers,

and then check whether the
system can run normally Yes
Yes

No

Replace IPM board, and

then check whether the Yes
system can run normally

No

Replace outdoor main board Trouble is solved

79
18.3.3.4 Outdoor unit fan speed has been out of control (E8)

Power
Power off,
off, then
then restart
restart thethe
unit 2 minutes later.
unit 2 minutes later. IsIs itit still
still No The
The unit
unit operates
operates normally.
normally.
displaying
displaying the
the error
error code?
code?

Yes
Find
Find out
out the
the cause
cause and
and
Shut
Shut offoff the
the power
power supply,
supply, have it solved.
have it solved. For
For
rotate
rotate the
the fan
fan by
by hand.
hand. Does
Does No example,
example, whether
whether the
the fan
fan
itit rotate isis blocked
blocked oror the
the screws
screws
rotate properly?
properly?
which
which fix
fix the
the fan
fan are
are
tighten.
tighten.
Yes

Check
Check the
the wiring
wiring ofof fan
fan
motor.
motor. Are
Are all
all the
the No Correct
Correct the
the connections.
connections.
connections
connections good?
good?

Yes

Check
Check whether
whether the
the main
main PCB
PCB No Replace
Replace the
the main
main PCB
PCB
isis normal
normal through
through index
index 1?
1?

Yes

Replace
Replace the
the fan
fan motor
motor No

Index 1:
1. Outdoor DC fan motor(control chip is inside fan motor)
Power on and when the unit is in standby, measure the voltage of pin1-pin3, pin4-pin3 in fan motor
connector. If the value of the voltage is not in the range showing in below table, the PCB must have
problems and need to be replaced.

DC motor voltage input and output

NO. Color Signal Voltage
1 Red Vs/Vm 140V~380V
2 --- --- ---
3 Black GND 0V
4 White Vcc 13.5-16.5V
5 Yellow Vsp 0~6.5V
6 Blue FG 15V

80
18.3.3.5 High pressure protection (ODU P1)(For 38QUS036DS4*, 38QUS042DS5*)

High
High pressure
pressure protection
protection

Whether
Whether the the wiring
wiring
between
between thethe high
high pressure
pressure
switch
switch and
and main
main control
control No Connect
Connect itit well
well
board
board is
is connected
connected well
well or
or
correctly
correctly

Yes

Whether
Whether the
the high
high
pressure
pressure protector
protector
is
is broken
broken

Method:
Method: Disconnect
Disconnect the
the plug.
plug.
Measure
Measure the
the resistance of the
resistance of the
high
high pressure
pressure protector,
protector, ifif No Replace
Replace high
high pressure
pressure protector
protector
the
the protector
protector is
is normal
normal thethe
value
value is
is o,
o,

Yes

Check
Check whether
whether the
the outdoor
outdoor
ambient
ambient temperature
temperature isis Yes Stop
Stop the
the unit
unit
higher
higher than
than 50℃
50℃

No

Check
Check ifif the
the outdoor
outdoor unit
unit
ventilation
NO Make
Make the
the outdoor
outdoor unit
unit ventilate
ventilate well
well
ventilation isis good
good

Yes
please
please refer
refer to
to the
the solution
solution of
of fan
fan
Check
Check ifif the
the outdoor
outdoor fan
fan runs
runs speed
speed has
has been
been outout of
of control
control
No malfunction
malfunction .. Find
Find out
out the
the cause
cause and
and
properly
properly
have
have itit solved.
solved.

Yes

Check
Check whether
whether the
the heat
heat
exchanger
Yes Clean
Clean the
the heat
heat exchanger
exchanger
exchanger is
is dirty
dirty

No
Replace
Replace outdoor
outdoor main
main
board
board

No

Check
Check whether
whether the
the refrigerant
refrigerant
system
system isis ok
ok

81
18.3.3.6 Low pressure protection (ODU P2)(For38QUS036DS4*, 38QUS042DS5*)

Low
Low pressure
pressure protection
protection

Whether
Whether the the wiring
wiring
between
between thethe low
low pressure
pressure
protector
protector and
and main
main control
control No Connect
Connect itit well
well
board
board is
is connected
connected well
well or
or
correctly
correctly

Yes

Whether
Whether thethe low
low
pressure
pressure protector
protector
is
is broken
broken

Method:
Method: Disconnect
Disconnect the
the plug.
plug.
Measure
Measure the
the resistance
resistance of
of the
the
low
low pressure
pressure protector.
protector. If
If the
the No Replace
Replace low
low pressure
pressure protector
protector
protector
protector is
is normal
normal the
the value
value isis
oo

Yes

Check
Check whether
whether the
the outdoor
outdoor
ambient
ambient temperature
temperature is
is too
too Yes Stop
Stop the
the unit
unit
low
low

No

Check
Check whether
whether valve
valve core
core
Open
Open fully
fully valve
valve core
core of
of
of
of high
high pressure
pressure valve
valve is
is No
high
high pressure
pressure valve
valve
opened
opened

Yes
please
please refer
refer to
to the
the solution
solution of
of fan
fan
Check
Check ifif the
the indoor
indoor fan
fan runs
runs speed
speed has
has been
been out
out of
of control
control
No malfunction.
malfunction. Find
Find out
out the
the cause
cause and
and
properly
properly in in cooling
cooling mode
mode
have
have itit solved.
solved.

Yes

Replace
Replace outdoor
outdoor main
main board
board

No
Refrigerant
Refrigerant isis not
not enough
enough add
add the
the
refrigerant
refrigerant

No

Check
Check whether
whether the
the refrigerant
refrigerant
system
system isis ok
ok

82
18.3.3.7 Current protection of compressor (ODU P3)

Current protection of compressor

Judge 1: Check whether the

input current of the power
supply wire is higher than max
protection current value

Yes

Check whether
the refrigerant
system is ok

Judge 2: Check whether the

outdoor ambient
Yes Stop the unit
temperature is higher than
50℃

No

Judge 3: Check whether the

Yes Make the outdoor unit ventilate well
outdoor unit is bad ventilation

No

Judge 4: Check whether the

Yes Clean the heat exchanger
heat exchanger is dirty

No

Let the refrigerant out, then use the high

Judge 5: The refrigerant
Yes pressure nitrogen or refrigerant to blow pipe,
pipe is blocked
vacuumize and charge the refrigerant again

No

Replace outdoor main

board,and check whether Yes
the system can run normally

No

Replace the electric control box Yes Trouble is solved

83
18.3.3.8 Temperature protection of compressor discharge (ODU P4)

Temperature
Temperature protection
protection of
of
compressor
compressor discharge
discharge

Check
Check whether
whether the
the
compressor Check
Check whether
whether the the
compressor discharge
discharge temp.
temp. isis Yes Yes Stop
Stop leaking
leaking and
and add
add refrigerant
refrigerant
refrigerant
refrigerant isis leak
leak
more than 115°C
more than 115°C ??

No
No

Check
Check whether
whether the
the
connection
connection isis right
right between
between
compressor
compressor discharge
discharge temp.
temp. No Correct
Correct the
the wiring
wiring connection
connection
sensor
sensor and
and PCB
PCB according
according
to
to wiring
wiring diagrams?
diagrams?

Yes

Measure
Measure thethe resistance
resistance value
value
of compressor
of compressor discharge
discharge
temp.
temp. sensor.
sensor. IfIf the
the value
value is
is No Replace
Replace the
the compressor
compressor discharge
discharge temp.
temp. sensor
sensor
not normal is
not normal is normal
normal refer
refer to
to
the
the Appendix
Appendix 2?
2?

Yes

Replace
Replace outdoor
outdoor main
main PCB
PCB

No

Replace
Replace high
high pressure
pressure valve
valve assy
assy

84
18.3.3.9 High temperature protection of condenser (ODU P5)
When outdoor pipe temperature is more than 65°C, the unit will stop, and unit runs again when outdoor pipe
temperature less than 52°C.

Check
Check the
the connection
connection
between
between temperature
temperature No Correct
Correct the
the connection
connection
High
High temperature
temperature protection
protection of
of No sensor
sensor and
and PCB.
PCB.
condenser
condenser

Yes

Check
Check whether
whether the
the
condenser
condenser temperature
temperature is
is Check
Check whether
whether the
the
Higher
Higher than
than 65°
65°C
C resistance
resistance of of condenser
condenser
temp.
temp. sensor
sensor is
is normal
normal
No Replace
Replace the
the temperature
temperature sensor
sensor
refer
refer to
to the
the Appendix
Appendix 11
Yes

Check
Check whether
whether the
the outdoor
outdoor
ambient
ambient temperature
temperature isis Yes Stop
Stop the
the unit
unit
higher
higher than
than 50℃
50℃

No

Check
Check ifif the
the outdoor
outdoor unit
unit
ventilation
No Make
Make the
the outdoor
outdoor unit
unit ventilate
ventilate well
well
ventilation isis good
good

Yes
please
please refer
refer to
to the
the solution
solution of
of fan
fan
Check
Check ifif the
the outdoor
outdoor fan
fan runs
runs speed
speed has
has been
been outout of
of control
control
No malfunction
malfunction .. Find
Find out
out the
the cause
cause and
and
properly
properly
have
have itit solved.
solved.

Yes

Check
Check whether
whether the
the heat
heat
exchanger
Yes Clean
Clean the
the heat
heat exchanger
exchanger Yes
exchanger is
is dirty
dirty

No
Replace
Replace outdoor
outdoor main
main
board
board

No
Refrigerant
Refrigerant isis not
not enough
enough add
add the
the
refrigerant
refrigerant

No

Check
Check whether
whether the
the refrigerant
refrigerant
system
system isis ok
ok

85
18.3.3.10 IPM module protection (ODU P6)
IPM module protection

Check whether the voltage range

Check whether the input Regulate it to correct, then
of P-N on IPM module is normal?
No power supply is correct? No check whether the system
DC277-356V for 18-28KBtu/h;
208-230V, 1N, 60Hz can work normally?
DC277-410V for 36-42KBtu/h

Yes

Yes No

Check whether the connecting

line between main board and Connect it tightly,
No
the IPM module is connected check ok or not? Check whether the
Connect it correctly
tightly power supply line is
No and tightly, check ok
connected correctly and
or not?
tightly

Yes
No
Yes No

Check whether the connecting

Connect it well, check
line of the compressor is No
ok or not?
connected correctly or tightly Check whether the lines
Connect it tightly,
in E-part box are No
check ok or not?
connected tightly

Yes
No

Yes No
Replace the IPM module,
check whether the system can
work normally? Check whether the bridge rectifiers are
normal? Use the multimeter to measure
the resistance between each two
terminals, check whether there is the
No condition that value of resistance is 0
No
Check whether the resistance of
the fan motor is normal. If not, Yes
Check if the outdoor fan replace the fan motor. For other Yes
runs properly or the outdoor Yes models, refer to the solution of Replace the bridge rectifiers
unit ventilation is good. fan speed has been out of
control malfunction . F i n d o u t
Check whether the connecting line of
the cause and have it solved. every reactor is normal? If the line is
broken, the resistance of the two ports is
No ∞（models except for M4OA-36HFN1-
Q,M4OD-28HFN1-Q, M5OC-36HFN1-
Q）；Check whether the PFC module
broken (for M4OA-36HFN1-Q,M4OD-
No
Replace the main board; check 28HFN1-Q, M5OC-36HFN1-Q,M50D-
whether the system can work Yes 42HFN1-Q)
normally?
Replace the connecting line or
reactor or replace the PFC
module(for M4OC-36HRFN1-
No M,M50D-42HFN1-Q)

Replace the compressor, check

Yes whether the system can work Yes
normally?

Trouble is solved

86
18.4 Main parts check
Spec.
Indoor unit
9K/12K/18K/24K 9K/12K/18K 9K/12K 18K/24K
Model
Cassette Console Ducted DL
Indoor fan motor ZKFP-46-8-1 ZKFP-20-8-2 ZKFN-55-8-1 ZKFN-55-8-1
24K 18K/24K
Model
Cassette Ducted
Indoor fan motor ZKFP-124-8-2 ZKFN-160-8-1-2
Outdoor unit
Model 1x2(14k) 1x2(18k) 1x3(21K) 1x3(27K)
Compressor ASN108D22UEZ ASM135D23UFZ ASM135D23UFZ ATF235D22UMT
Outdoor fan
ZKFN-40-8-1L ZKFN-40-8-1L ZKFN-50-8-2 ZKFN-50-8-2
motor
Model 1x4(28K) 1x4(36K) 1x5(42K)
Compressor ATF235D22UMT ATF310D43UMT ATF310D43UMT
Outdoor fan
ZKFN-120-8-2 ZKFN-120-8-2 ZKFN-120-8-2
motor

87
1. Temperature sensor checking
Disconnect the temperature sensor from PCB, measure the resistance value with a tester.

Temperature Sensors.
Room temp.(T1) sensor,
Indoor coil temp.(T2) sensor,
Outdoor coil temp.(T3) sensor,
Outdoor ambient temp.(T4) sensor,
Compressor discharge temp.(T5) sensor.
Measure the resistance value of each winding by using the multi-meter.

88
Appendix 1 Temperature Sensor Resistance Value Table for T1,T2,T3,T4,T2B (℃--K)
℃ K Ohm ℃ K Ohm ℃ K Ohm ℃ K Ohm
-20 115.266 20 12.6431 60 2.35774 100 0.62973
-19 108.146 21 12.0561 61 2.27249 101 0.61148
-18 101.517 22 11.5000 62 2.19073 102 0.59386
-17 96.3423 23 10.9731 63 2.11241 103 0.57683
-16 89.5865 24 10.4736 64 2.03732 104 0.56038
-15 84.2190 25 10.000 65 1.96532 105 0.54448
-14 79.3110 26 9.55074 66 1.89627 106 0.52912
-13 74.5360 27 9.12445 67 1.83003 107 0.51426
-12 70.1698 28 8.71983 68 1.76647 108 0.49989
-11 66.0898 29 8.33566 69 1.70547 109 0.48600
-10 62.2756 30 7.97078 70 1.64691 110 0.47256
-9 58.7079 31 7.62411 71 1.59068 111 0.45957
-8 56.3694 32 7.29464 72 1.53668 112 0.44699
-7 52.2438 33 6.98142 73 1.48481 113 0.43482
-6 49.3161 34 6.68355 74 1.43498 114 0.42304
-5 46.5725 35 6.40021 75 1.38703 115 0.41164
-4 44.0000 36 6.13059 76 1.34105 116 0.40060
-3 41.5878 37 5.87359 77 1.29078 117 0.38991
-2 39.8239 38 5.62961 78 1.25423 118 0.37956
-1 37.1988 39 5.39689 79 1.21330 119 0.36954
0 35.2024 40 5.17519 80 1.17393 120 0.35982
1 33.3269 41 4.96392 81 1.13604 121 0.35042
2 31.5635 42 4.76253 82 1.09958 122 0.3413
3 29.9058 43 4.57050 83 1.06448 123 0.33246
4 28.3459 44 4.38736 84 1.03069 124 0.32390
5 26.8778 45 4.21263 85 0.99815 125 0.31559
6 25.4954 46 4.04589 86 0.96681 126 0.30754
7 24.1932 47 3.88673 87 0.93662 127 0.29974
8 22.5662 48 3.73476 88 0.90753 128 0.29216
9 21.8094 49 3.58962 89 0.87950 129 0.28482
10 20.7184 50 3.45097 90 0.85248 130 0.27770
11 19.6891 51 3.31847 91 0.82643 131 0.27078
12 18.7177 52 3.19183 92 0.80132 132 0.26408
13 17.8005 53 3.07075 93 0.77709 133 0.25757
14 16.9341 54 2.95896 94 0.75373 134 0.25125
15 16.1156 55 2.84421 95 0.73119 135 0.24512
16 15.3418 56 2.73823 96 0.70944 136 0.23916
17 14.6181 57 2.63682 97 0.68844 137 0.23338
18 13.9180 58 2.53973 98 0.66818 138 0.22776
19 13.2631 59 2.44677 99 0.64862 139 0.22231

89
Appendix 2 Temperature Sensor Resistance Value Table for T5 (℃--K)
℃ K Ohm ℃ K Ohm ℃ K Ohm ℃ K Ohm

-20 542.7 20 68.66 60 13.59 100 3.702

-19 511.9 21 65.62 61 13.11 101 3.595
-18 483 22 62.73 62 12.65 102 3.492
-17 455.9 23 59.98 63 12.21 103 3.392
-16 430.5 24 57.37 64 11.79 104 3.296
-15 406.7 25 54.89 65 11.38 105 3.203
-14 384.3 26 52.53 66 10.99 106 3.113
-13 363.3 27 50.28 67 10.61 107 3.025
-12 343.6 28 48.14 68 10.25 108 2.941
-11 325.1 29 46.11 69 9.902 109 2.86
-10 307.7 30 44.17 70 9.569 110 2.781
-9 291.3 31 42.33 71 9.248 111 2.704
-8 275.9 32 40.57 72 8.94 112 2.63
-7 261.4 33 38.89 73 8.643 113 2.559
-6 247.8 34 37.3 74 8.358 114 2.489
-5 234.9 35 35.78 75 8.084 115 2.422
-4 222.8 36 34.32 76 7.82 116 2.357
-3 211.4 37 32.94 77 7.566 117 2.294
-2 200.7 38 31.62 78 7.321 118 2.233
-1 190.5 39 30.36 79 7.086 119 2.174
0 180.9 40 29.15 80 6.859 120 2.117
1 171.9 41 28 81 6.641 121 2.061
2 163.3 42 26.9 82 6.43 122 2.007
3 155.2 43 25.86 83 6.228 123 1.955
4 147.6 44 24.85 84 6.033 124 1.905
5 140.4 45 23.89 85 5.844 125 1.856
6 133.5 46 22.89 86 5.663 126 1.808
7 127.1 47 22.1 87 5.488 127 1.762
8 121 48 21.26 88 5.32 128 1.717
9 115.2 49 20.46 89 5.157 129 1.674
10 109.8 50 19.69 90 5 130 1.632
11 104.6 51 18.96 91 4.849
12 99.69 52 18.26 92 4.703
13 95.05 53 17.58 93 4.562
14 90.66 54 16.94 94 4.426
15 86.49 55 16.32 95 4.294 B(25/50)=3950K
16 82.54 56 15.73 96 4.167
17 78.79 57 15.16 97 4.045 R(90℃)=5KΩ±3%
18 75.24 58 14.62 98 3.927
19 71.86 59 14.09 99 3.812

90
2.Compressor checking
Measure the resistance value of each winding by using the tester.

Position Resistance Value

ASN108D22UEZ ASM135D23UFZ ATF235D22UMT ATF310D43UMT

Blue -
1.57Ω(20℃) 1.75Ω(20℃) 0.75Ω(20℃) 0.65Ω(20℃)
Red

91
3. IPM continuity check
Turn off the power, let the large capacity electrolytic capacitors discharge completely, and dismount the IPM. Use a digital
tester to measure the resistance between P and UVWN; UVW and N.
Digital tester Normal resistance value Digital tester Normal resistance value

(+)Red (-)Black (+)Red (-)Black

N U
∞ ∞
U V
P (Several MΩ) N (Several MΩ)
V W

W (+)Red

92