A319/ A320/ A321

TECHNICAL TRAINING MANUAL

ATA 38

WATER AND WASTE

Under no circumstances should this document be used as a reference

This document must be used for training purposes only.

Future updates will not be issued to the holder of this manual.

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WATER AND WASTE – TABLE OF CONTENTS

GENERAL
System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
MEL/ Deactivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Maintenance Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
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POTABLE WATER (A320)
Potable Water System D/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
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POTABLE WATER (A319/A321) (Classic)
Potable Water System D/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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POTABLE WATER (Enhanced)
Potable Water System D/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
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WASTE WATER
Waster Water System D/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
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TOILET (Classic)
Toilet System Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Toilet System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
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TOILET (Enhanced)
Toilet System Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Toilet System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
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MAINTENANCE PRACTICE
Potable Water SYS Servicing (A320) . . . . . . . . . . . . . . . . . . . . . . . . . .43
Potable Water SYS Servicing (A318/A319/A321) . . . . . . . . . . . . . . . . 49
Toilet System Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
I

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SYSTEM OVERVIEW
The water and waste system consist of three subsystems:
- Potable water system
- Waste water system
- Toilet system

WATER AND WASTE FLUID STORAGE (A318, A319 AND A321)

The potable water tank and the waste holding tank are installed in the
pressurized underfloor area LH rear the aft cargo compartment. An
indication system monitors the water and waste tank quantities.

POTABLE WATER SYSTEM

The potable water system supplies water from the water tank through a
distribution system to the user. The water is supplied to water faucets in
the galleys and lavatories. The system also supplies water to the water
heaters and vacuum toilet units. Mechanically or electrically operated
valves control the supply of the potable water system.
Compressed air is used to pressurize the system to supply water from
the tank to the necessary service locations. The air pressure is supplied
from the bleed air system in normal configuration or a ground pressure
connection for maintenance. An air compressor can be installed as an
option. Each lavatory can be isolated from the potable water distribution
system through a manual shut-off valve.

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SYSTEM OVERVIEW - WATER AND WASTE FLUID STORAGE (A318, A319 AND A321) & POTABLE WATER SYSTEM
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SYSTEM OVERVIEW
WATER AND WASTE FLUID STORAGE (A320)

For the A320 only, the location of the potable water tank is aft of the
forward cargo compartment.

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SYSTEM OVERVIEW - WATER AND WASTE FLUID STORAGE (A320)

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SYSTEM OVERVIEW
POTABLE WATER HEATING, ICE PROTECTION AND
WINTERIZATION PROTECTION

One water heater is installed in each lavatory and in each galley. Water
pipes, where icing conditions can occur are insulated and heated by
tape electrical heaters. The potable water service panel is heated to
prevent ice formation. Optionally, the fill/drain nipple and overflow
nipple are also electrically heated. These heating elements are
controlled automatically by two anti-ice control units installed in the
cargo compartments. In winter conditions, the potable water system
must be drained during night stops.

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SYSTEM OVERVIEW - POTABLE WATER HEATING, ICE PROTECTION AND WINTERIZATION PROTECTION
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SYSTEM OVERVIEW
POTABLE WATER CONTROL AND INDICATING (FAP)

The water and waste indications are displayed on the Forward

Attendant Panel (FAP) or on the Flight Attendant Panel (FAP) for
aircraft fitted with enhanced cabin systems. On the Forward Attendant
Panel, the quantity indication is displayed automatically as soon as the
service panel is open, or if the INDication ON P/B is pressed. On the
Flight Attendant Panel, the quantity indication is also displayed
automatically as soon as the service panel is open, or when the
Water/Waste key on the FAP is selected. As an option, the filling
quantity can be selected (25%, 50%, 75% and 100%).

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SYSTEM OVERVIEW - POTABLE WATER CONTROL AND INDICATING (FAP)

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SYSTEM OVERVIEW
POTABLE WATER CONTROL AND INDICATING (SERVICE PANEL)

There is only one control handle to fill or drain the water tank. It is
located on the water service panel. On A320 aircrafts, two drain valves
are electrically controlled when the fill/drain control handle is set to the
drain position. The overflow valve opens electrically when the fill/drain
valve handle is set to the drain or fill position. On the servicing panel,
the indicator gives the water quantity. Two green lights indicate that the
drain valves are open. One green light indicates that the overflow valve
is open. One green light indicates that the tank is full. All three drain
valves and the overflow valve can be opened manually. On A318, A319
and A321, one green light indicates that the forward drain valve is open
and one green light indicates that the tank is full.

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SYSTEM OVERVIEW - POTABLE WATER CONTROL AND INDICATING (SERVICE PANEL)

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SYSTEM OVERVIEW
WASTE WATER SYSTEM

The waste water system drains the used water from the lavatory
washbasins and the galley sinks. The waste water is discarded
overboard outside through the drain valve and the drain mast. The two
drain masts and drain lines have integrated electrical heating elements
to prevent ice formation at high altitude or during cold weather.

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SYSTEM OVERVIEW - WASTE WATER SYSTEM

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SYSTEM OVERVIEW
TOILET SYSTEM (CLASSIC) TOILET SYSTEM CONTROL AND INDICATING

The toilet system gives sanitary facilities for the passengers and crews. The VSC controls the system and related electronic components. A Flush
The system is a vacuum type toilet system and uses potable water for Control Unit (FCU) per toilet controls the rinse and flush cycle as soon as
flushing. the flush switch is pressed. On the Forward Attendant Panel (FAP), the
quantity indication is displayed as soon as the IND ON P/B is pressed.
TOILET SYSTEM FLUSHING OPERATION On the servicing panel, the waste control handle is used to drain the
waste holding tank.
The system uses potable water from the aircraft pressurized water
system to flush the toilet. A vacuum drain valve removes waste from
the toilet bowl to an under floor waste holding tank. At high altitude, the
differential pressure between the cabin and the atmospheres is
sufficient to move the waste from the toilet bowl into the waste holding
tank. At low altitude or on ground, a vacuum generator starts to give the
necessary differential pressure in the waste system to move the waste
from the bowl to the tank. The Vacuum System Controller (VSC)
controls the flushing system operation and stops the operation when
the waste servicing panel is open. When the tank is full, the liquid level
transmitter stops the system operation.

TOILET SYSTEM WASTE DISPOSAL

The waste holding tank is installed on the right of the aircraft under the
floor behind the bulk cargo compartment. The tank includes a water
separator, a liquid level transmitter, a liquid level sensor, a waste drain
valve and two rinse line connections.

TOILET SYSTEM WASTE TANK HEATING (OPTIONAL)

The waste holding tank can be insulated. The lines between the tank
and the service panel with the waste drain valve can be insulated and
heated.

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SYSTEM OVERVIEW - TOILET SYSTEM (CLASSIC) ... TOILET SYSTEM CONTROL AND INDICATING
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SYSTEM OVERVIEW
TOILET SYSTEM (ENHANCED)

On enhanced systems, the vacuum toilet system is connected to the

Cabin Intercommunication Data System (CIDS).The CIDS controls and
monitors the system functions and the related electric components.
The system uses potable water from the potable water system to rinse
the toilet bowl. When the waste holding tank is full, a signal is sent to
the CIDS, which shuts down the toilet systems. The Flight Attendant
Panel (FAP) displays the waste tank quantity stored in the waste
holding tank when the Water/Waste key on the FAP is selected.

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SYSTEM OVERVIEW - TOILET SYSTEM (ENHANCED)

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SERVICING
POTABLE WATER SERVICING

The potable water system supplies the galleys and toilets with water
from the tank via a distribution system. The tank is pressurized by air
either:
- From the pneumatic system,
- Or from a ground cart connected to the ground connector,
- Or optionally from a compressor.

On the A320 only, two valves are used for filling:

- The fill/drain valve, this is opened manually and closed electrically,
- The overflow valve, this is opened and closed electrically,
Four valves are used for draining:
- The fill/drain valve, this is opened and closed manually,
- The FWD drain valve, tank drain valve and overflow valve, these
are opened and closed electrically.

NOTE: On A320, if there is no electrical power all four valves can be

manually operated.

On A318, A319 and A321, one valve is used for filling:

- The overflow/fill/drain valve, this is opened manually and closed
electrically,
Two valves are used for draining:
- The overflow/fill/drain valve, this is manually operated,
- The FWD drain valve, this is electrically operated.

NOTE: On A318, A319 and A321, if there is no electrical power both

valves must be manually operated.

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SERVICING - POTABLE WATER SERVICING

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SERVICING
TOILET SYSTEM SERVICING

Connect the toilet service vehicle to the toilet service panel. Move the
drain valve control-handle from the close to the open position.
Drain the waste from the toilet tank.
Flush the toilet system.
Fill the toilet tank with 10 l of disinfectant solution.

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SERVICING - TOILET SYSTEM SERVICING

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MEL/DEACTIVATION
If the drain mast is not heated, the aircraft can be dispatched provided
that the associated galleys or toilets are not used (toilet door locked
and placarded "Inoperative'') and their water shut off valves are closed.

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MEL/DEACTIVATION
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MAINTENANCE TIPS
POTABLE WATER SYSTEM DRAINING IN COLD WEATHER
CONDITIONS

In cold weather conditions the potable water system must be drained to

prevent damage to the system by ice. To decide if the potable water
system needs be drained, we must refer to the water system drain
configuration table in the AMM 12-24-38. If the bleed air system is off
and the outside air temperature is below 0 °C (32 °F), the drain valves
must remain open after the potable water system is drained to prevent
damage to the potable water system. The cold weather maintenance
practices for the potable water system are given in the AMM 12-31-38.

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MAINTENANCE TIPS - POTABLE WATER SYSTEM DRAINING IN COLD WEATHER CONDITIONS

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POTABLE WATER SYSTEM D/O

STORAGE 118,4 °F). An over temperature safety device protects the heating
element.
The potable water is stored in one tank installed in the pressurized
underfloor area of the right hand fuselage, aft of the forward cargo INDICATING
compartment. The potable water tank has a capacity of 200 l (53 US
gal). The quantity indication system indicates how much water is available in
the potable water tank. The quantity transmitter transmits the signal to
PRESSURIZATION the indicator on the water service panel and to the Forward Attendant
Panel (FAP). The TANK FULL light on the service panel comes on when
Pressurization of the system enables water supply from the tank to the the tank is full.
necessary service location. Compressed air is tapped from the cross
feed line of the engine or APU bleed air. On ground, when the bleed air FILLING
system is not available, the ground air pressure supply system is used.
If installed, an optional compressor is used for the pressurization in The Filling is achieved through a fill/drain valve operated by the fill/drain
case of bleed air decrease. During servicing, the overflow valve lets the control handle on the potable water service panel. The fill/drain control
potable water tank depressurized. handle simultaneously opens the electrically motorized overflow valve for
venting. The quantity transmitter sends a tank-full signal to close the
DISTRIBUTION fill/drain valve automatically. Manual operation is possible via control
handles dedicated to each valve. Maximum permissible pressure to fill
Potable water from the water tank is supplied through a system of the potable water tank is 50 psi (3.4 bars).
distribution lines. The lavatory and galley distribution lines run below
the passenger compartment floor. They are shrouded and insulated, CAUTION: WITHOUT ELECTRICAL POWER YOU MUST OPEN THE
and some of them are electrically heated to prevent ice formation. OVERFLOW VALVE MANUALLY PRIOR TO THE FILLING
TO PREVENT WATER SPILLAGE IN THE CABIN.
USER SUPPLY
DRAINING
Each lavatory can be isolated from the potable water distribution
system through a manual Shut-Off Valve (SOV). The draining operation is achieved through the fill/drain valve and two
motorized drain valves using the same control handle as the filling
HEATING operation. In this case, the overflow valve is also controlled to open.
Manual operation is possible via control handles dedicated to each valve.
A water heater is installed under the wash basin inside the sanitary unit
cabinet. If the quantity transmitter detects a low level into the water
tank, it cuts the electrical supply of the water heater. A thermostat
allows the water temperature to be maintained between 45 °C (113 °F)
and 48 °C

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STORAGE ... DRAINING

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POTABLE WATER SYSTEM D/O

STORAGE the indicator on the water service panel and to the Forward Attendant
Panel (FAP). The TANK FULL light on the service panel comes on when
The potable water tank with a capacity of 200 l (53 US gal) is installed the tank is full.
in the LH pressurized under floor area behind the rear cargo
compartment. SERVICING

PRESSURIZATION The Servicing of the potable water system can be done with or without
electrical power. With electrical power, the single fill/drain handle
Compressed air is used to pressurize the system in order to supply mechanically operates the fill/overflow drain valve and electrically
water from the tank to the necessary service locations. The controls the forward drain valve. Without electrical power, the valves are
compressed air is tapped from the cross feed-line of the engine or APU individually operated by cables. The draining operation is accomplished
bleed air and is connected to the water tank air inlet. On ground, when by opening the fill/overflow drain valve and the forward drain valve. The
the bleed air system is not available, the ground air pressure supply filling operation is accomplished by opening the fill/overflow drain valve
system is used. If installed, an optional compressor is used for the and closing the forward drain valve. When the tank is full, the quantity
pressurization in case of bleed air decrease. transmitter sends a signal to close the fill/overflow drain valve
automatically.
DISTRIBUTION

Potable water from the water tank is supplied through a system of

distribution lines, which are routed below the passenger compartment
floor. A part of the forward distribution line goes through a hose for
added protection. The potable water distribution lines are insulated and
electrically heated to prevent ice formation in and around the lines.

HEATING

In each lavatory, a water heater is installed under the wash basin. If the
quantity transmitter detects a low level into the water tank, it cuts the
electrical supply of the water heater. A thermostat maintains the water
temperature between 45°C (113°F) and 48°C (118.4°F). An over
temperature safety device protects the heating element.

INDICATING

The quantity indication system indicates how much water is available in

the potable water tank. The quantity transmitter transmits the signal to

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STORAGE ... SERVICING

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POTABLE WATER SYSTEM D/O

STORAGE the indicator on the water service panel. It also sends the information to a
Decoder/Encoder Unit (DEU) B, which in turn interfaces with the active
The potable water tank with a capacity of 200 l (53 US gal) is installed Cabin Intercommunication Data System (CIDS) director to display on the
in the pressurized LH under floor area behind the rear cargo Flight Attendant Panel (FAP) the water tank contents in percentage of
compartment. volume. The TANK FULL light on the service panel comes on when the
tank is full.
PRESSURIZATION
SERVICING
Compressed air is used to pressurize the system in order to supply
water from the tank to the necessary service locations. The The Servicing of the potable water system can be done with or without
compressed air is tapped from the cross feed-line of the engine or APU electrical power. With electrical power, the single fill/drain control handle
bleed air and is connected to the water tank air inlet. On ground, when mechanically operates the fill/overflow drain valve and electrically controls
the bleed air system is not available, the ground air pressure supply the forward drain valve. Without electrical power, the valves are
system is used. If installed, an optional compressor is used for the individually operated by cables. The draining operation is accomplished
pressurization in case of bleed air decrease. by opening the fill/overflow drain valve and the forward
drain valve. The filling operation is accomplished by opening the
DISTRIBUTION fill/overflow drain valve and closing the forward drain valve. When the
tank is full, the quantity transmitter sends a signal to close the fill/overflow
Potable water from the water tank is supplied through a system of drain valve automatically.
distribution lines, which are routed below the passenger compartment
floor. A part of the forward distribution line goes through a hose for
added protection. The potable water distribution lines are insulated and
electrically heated to prevent ice formation in and around the lines.

HEATING

In each lavatory, a water heater is installed under the wash basin. If the
quantity transmitter detects a low level into the water tank, it cuts the
electrical supply of the water heater. A thermostat maintains the water
temperature between 45°C (113°F) and 51.7°C (125°F). An over
temperature safety device protects the heating element.

INDICATING

The quantity indication system indicates how much water is available in

the potable water tank. The quantity transmitter transmits the signal to

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STORAGE ... SERVICING

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WASTER WATER SYSTEM D/O

GENERAL

The waste water drain system discards the waste water from the
lavatory wash basins and from the galley sinks.

DRAIN ASSEMBLY

Each lavatory wash basin has a drain assembly with a valve actuated
by a control knob and a cable.

NOTE: The control knob is operated by the lavatory user.

DRAIN VALVE

Each drain valve opens only when a certain amount of water is

collected. This prevents a permanent loss of cabin air pressurization
through the drain lines.

DRAIN MAST

In flight, differential pressure between the cabin and the drain mast
outlet discards the waste water. On ground, gravity discards the waste
water.
The drain masts are electrically heated to prevent ice formation.

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GENERAL ... DRAIN MAST

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TOILET SYSTEM PRINCIPLE

GENERAL

Potable water from the aircraft pressurized potable water system is

used to flush the toilet bowl. Differential pressure between the cabin
and the atmosphere moves the waste from the toilet bowl to the waste
holding tank. This difference of pressure can be caused by the vacuum
generator or by aircraft pressurization.

RINSE/FLUSH CONTROL

A flush control unit per toilet controls the flushing cycle.

VACUUM CONTROL

As soon as a FLUSH switch is pressed, electrical power is supplied to

the Vacuum System Controller (VSC). At high altitude, the altitude
pressure switch stops the electrical supply of the vacuum generator, the
differential pressure between the cabin and the atmosphere being
sufficient to move the waste from the toilet bowl to the waste holding
tank. At low altitude or on ground, the altitude pressure switch stays
closed. The vacuum generator generates the necessary differential
pressure.

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GENERAL ... VACUUM CONTROL

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TOILET SYSTEM DESCRIPTION

GENERAL - a water separator,
- a liquid level transmitter (hydrostatic pressure),
The toilet system removes waste from the toilet bowl through a vacuum - a liquid level sensor (ultrasonic type),
drain to an underfloor waste holding tank. An electronic Vacuum - waste inlets,
System Controller (VSC) controls and monitors the system and the - a waste outlet,
related electric components. The system uses potable water from the - two flush inlet nozzles.
potable water system to flush the toilet.
CONTROL/MONITORING
FLUSHING
The VSC controls and monitors the toilet system operation. It also reports
When the FLUSH switch is pressed, the flush control unit initiates the the vacuum toilet system failures to the Centralized Fault Display System
flush sequence. The vacuum generator starts to operate and after 1.6 (CFDS) and to the RS 232-C interface for shop maintenance.
seconds the water valve opens for 1.7 seconds. Then, the flush valve,
controlled by the flush control unit, opens for 4 seconds to evacuate the INDICATING
waste material through differential pressure.
The waste holding tank is equipped with a liquid level transmitter and a
VACUUM liquid level sensor. When the tank is full, the VSC shuts down the toilet
systems and sends a "SYSTEM INOP" message to the Forward
As soon as the FLUSH switch is pressed, the flush control unit sends Attendant Panel (FAP).
an electrical signal to the VSC, which operates the vacuum generator
for approximately 15 seconds. The vacuum generator creates the SERVICING
necessary differential pressure between the cabin and the waste
holding tank to move the waste from the toilet bowl. Above 4877 m The waste holding tank is serviced from a service panel, which is located
(16000 ft) altitude during climb and down to 3658 m (12000 ft) altitude on the right hand side of the lower fuselage between FR 65 and FR 66.
during descent, the VSC receives an electrical signal from the altitude It has:
switch and stops the electrical power to the vacuum generator. - a drain connection,
- a rinse/flush connection,
NOTE: The landing gear signal is used as a back up in case of altitude - an optional waste quantity indicator,
pressure switch failure. - a waste drain valve control handle,
- a limit switch.
STORAGE During servicing, the flush control units are automatically de-activated.
Thus, toilet use is inhibited during servicing. The waste drain control
The waste holding tank is installed on the right hand side of the aircraft handle mechanically operates the drain valve.
under the floor between FRame 65 and FR 68. The tank has a capacity
of 170 l (44.9 US gal). The tank has:

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GENERAL ... SERVICING

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TOILET SYSTEM PRINCIPLE

GENERAL

Potable water from the aircraft pressurized potable water system is

used to flush the toilet bowl. Differential pressure between the cabin
and the atmosphere moves the waste from the toilet bowl to the waste
holding tank. This difference of pressure can be caused by the vacuum
generator or by aircraft pressurization.

RINSE/FLUSH CONTROL

A flush control unit per toilet controls the time and sequence of the toilet
operation during the flushing cycle.

VACUUM CONTROL

A vacuum generator is connected to the aircraft power circuit through

the motor starting relay. As soon as a FLUSH switch is pressed, the
flush control unit sends an electrical signal, through the connected
Decoder/Encoder Unit (DEU) B to the Cabin Intercommunication Data
System (CIDS) directors, which activates the motor starting relay
according to the altitude. The Cabin Pressure Controller (CPC) supplies
altitude data to CIDS via the System Data Acquisition Concentrator
(SDAC). At high altitude, the CPC stops the electrical supply of the
vacuum generator, the differential pressure between the cabin and the
atmosphere being sufficient to move the waste from the toilet bowl to
the waste holding tank. At low altitude or on ground, the vacuum
generator generates the necessary differential pressure.

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GENERAL ... VACUUM CONTROL

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TOILET SYSTEM DESCRIPTION

GENERAL STORAGE

The toilet system removes waste from the toilet bowl through a vacuum The waste holding tank is installed on the right hand side of the aircraft
drain to an underfloor waste holding tank. The vacuum toilet system is under the floor between FRame 65 and FR 68. The tank has a capacity of
connected to the Cabin Intercommunication Data System (CIDS), which 170 l (44.9 US gal). The tank has:
controls and monitors the system function and the related electric - a water separator,
components. The system uses potable water from the potable water - a liquid level transmitter (hydrostatic pressure),
system to flush the toilet. - a liquid level sensor (ultrasonic type),
- waste inlets,
FLUSHING - a waste outlet,
- two flush inlet nozzles.
When the FLUSH switch is pressed, the flush control unit initiates the
flush sequence. The vacuum generator starts to operate and after 1.6 CONTROL/MONITORING
seconds the water valve opens for 1.7 seconds. Then, the flush valve,
controlled by the flush control unit, opens for 4 seconds to evacuate the The waste system data is received by DEUs B and sent to the CIDS
waste material through differential pressure. directors (DIRs). This system is controlled and monitored by the Vacuum
System Controller (VSC) function, which is integrated inside the CIDS
VACUUM DIRs. It also reports the vacuum toilet system failures to the Centralized
Fault Display System (CFDS) and to the RS 232-C interface for shop
As soon as the FLUSH switch is pressed, the flush control unit sends maintenance.
an electrical signal to the CIDS (via the connected Decoder/Encoder
Unit (DEU) B), which operates the vacuum generator for approximately INDICATING
15 seconds. The vacuum generator creates the necessary differential
pressure between the cabin and the waste holding tank to move the The waste holding tank is equipped with a liquid level transmitter and a
waste from the toilet bowl. The vacuum generator is activated: liquid level sensor. When the tank is full, a signal is sent to the CIDS DIRs
- on ground, through the DEU B, which shuts down the toilet systems. The signal is
- during climb when the differential pressure is less than 246 mbar, also sent to the Flight Attendant Panel (FAP) through the DIRs and a
- during descent when the differential pressure is less than 203 mbar. "WASTE TANK NOT EMPTY-CHECK LEVEL GROUND SERVICE
The different pressure information is supplied by the Cabin Pressure REQUIRED" message is displayed.
Controller (CPC) via the System Data Acquisition Concentrator (SDAC).
SERVICING
NOTE: The landing gear signal is used as a back up in case of CPC or
SDACs failure. The waste holding tank is serviced from a service panel, which is located
on the right of the lower fuselage between FR 65 and FR 66. It has:
- a drain connection,

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- a rinse/flush connection,
- an optional waste quantity indicator,
- a waste drain valve control handle,
- a limit switch.

During servicing, the flush control units are automatically de-activated.

Thus, toilet use is inhibited during servicing. The waste drain control
handle mechanically operates the drain valve.

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THIS PAGE IS LEFT INTENTIONALLY BLANK

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GENERAL ... SERVICING

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POTABLE WATER SYS SERVICING (A320)

FILLING

The water service panel is located on the left side of the aft fuselage.
Electricity must be supplied to the panel. Use ground power and turns
on the MAINTenance BUS switch. When the panel door is open, the
light on the fill gauge indicates that the panel has power. As a back-up
check for electricity, press any one of the four indicator lights, they
should light up. Do not attempt to fill or empty the water system without
a powered panel. Also on panel are the fill and drain port and the
control handle.

To fill the water system, open the service door. Connect the fill hose to
the port. Turn the control handle counter clockwise to the FILL position
and pull out on the handle. Make sure the overflow valve opens: the
indicator light should light up. Turn on the water pump at the truck. The
quantity gauge will show when the system is taking on water. When the
tank is full the FULL light should come on. Turn off the pump of the
truck.
Push the control handle in and turn it back to the NORMAL position. On
some A320, the control handle is automatically pulled in and returns to
the NORMAL position by itself. Disconnect the hose and cap the port.
Before closing the door, clean and dry the service panel and check for
leaks, then close the access door.

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FILLING
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POTABLE WATER SYS SERVICING (A320)

DRAINING

Three drain ports controlled by the service panel are used to empty the
water system. The main drain port is located on the underside of the
aircraft directly below the water tank and next to the overflow port. A
few feet ahead of the main drain is another drain port for the forward lav
and galley lines. The port on the water service panel is used to drain
the lines for the rear lavs and galley. To drain the water system, move a
container under the main port.

At the control panel, uncap the port. Turn the control handle clockwise
to the DRAIN position and pull the handle out. Three indicator lights
should come on. They are: the OVERFLOW VALVE OPEN light, the
TANK DRAIN VALVE OPEN light and the FORWARD DRAINVALVE
OPEN light. Most of the water will come out of the main drain, only a
small amount will come out of the forward and aft drains. When the
system is drained, push the control handle in. Make sure that it returns
to the NORMAL position. All the indicator lights should go off. Replace
the drain cap.

Make sure the service panel is clean and dry. Then close the panel
door.

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DRAINING
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POTABLE WATER SYS SERVICING (A320)

MISCELLANEOUS

Without electricity, you will have to use the following manual overrides:
- for filling, open the overflow valve,
- for draining, open both valves of the main drain and the one of the
forward drain.

Maintenance will eventually replaced the X screw holding in this panel

shut with a P/B latch. Information on cold weather water servicing will
be provided by your instructor.

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MISCELLANEOUS
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POTABLE WATER SYS SERVICING (A318/A319/A321)

NORMAL FILLING

The water service panel is located on the left side of the aft fuselage.
Electricity must be supplied to the panel. Use ground power and turns
on the maintenance bus (MAINT BUS ON switch). When the service
panel is opened, the light on the fill gauge indicates that the panel has
power. Also on the panel are the fill and drain port and the control
handle.

To fill the water system, connect the fill hose to the port. Turn the
control handle counter clockwise to the FILL position and pull out on the
handle.
Turn on the water pump on the truck. The quantity gauge will show
when the system is taking on water. When the tank is full, the FULL
light comes on. The control handle returns to the NORMAL position by
itself. Turn off the pump on the truck. Disconnect the hose. Before
closing the door, clean and dry the service panel and check for leaks.
Then, close the access door.

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NORMAL FILLING
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POTABLE WATER SYS SERVICING (A318/A319/A321)

MANUAL FILLING

If electrical power is not available, the manual filling procedure must be

used. To fill the water system, open the servicing panel. Connect the fill
hose to the port. Turn the control handle counterclockwise to the FILL
position and pull out on the handle. Turn on the water pump on the
truck.
When the tank is full, the water comes out by the overflow port.
Manually push the control handle back in its NORMAL position. Turn off
the pump on the truck. Disconnect the hose. Before closing the door,
clean and dry the service panel and check for leaks. Then, close the
access door.

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MANUAL FILLING
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TOILET SYSTEM SERVICING

DRAINING

The lavatory service panel is located on the right side of the aft
fuselage.
Open the service door. The controls consist of a drain port, two valve
levers, a drain control handle and a filling port. To empty the waste
system, open the cap assembly and connect the drain hose and next to
it the fill hose. Next to the drain connection is a small lever marked
OPEN.
Push this lever in the direction of the arrow; the lever marked CLOSED
should rotate by spring action indicating that the valve has opened. Pull
the drain control handle outward to the extended position. This allows
waste materials to flow from the drain port. When the system is drained
return the control handle to the normal position. To flush the tank, use 5
gallons (19 l) of disinfectant commonly called "Blue Juice". Now drain
the system by extending the control handle. Once drained, return the
handle to the normal position. Replenish with 2 gallons (7,5 l) of blue
juice. You are now ready to disconnect hoses and replace the
connection caps on the drain and rinse ports. By closing the drain cap
the drain valve automatically closes. Clean and dry the panel with a
clean cloth and do not forget to close the service door. On the Forward
Attendant Panel:
- if the LAV indicator light is on, reservice the system,
- if the light remains on, contact maintenance or maintenance control.

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DRAINING
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