PARTS LIST

MM-701E

McDonnell & Miller

Service Parts Catalog
Table of Contents
Replacement Parts for: General Information
Boiler Controls . . . . . . . . . . . . . . . . . .5 Warranty & Return Policy . . . . . . . . . . . . . .68
Liquid Level Controls . . . . . . . . . . . .51 Maintenance & Replacement
Flow Switches . . . . . . . . . . . . . . . . . .55 Interval Guidelines . . . . . . . . . . . . . . .70

BoiLer ControL rePLaCement PartS

Low water Cut-oFFS For SerieS Page Low water Cut-oFFS For SerieS Page

• For Hot Water Boilers • For Steam Boilers

PS-800 Series
Replacement Probes
5

PS-850 5
Series
PSE-800 Series 5

RB Series 6
• Combination Low Water Cut-Off/
Pump Controllers for Steam Boilers
751P/752P Series 5

42/42A and 18
• For Steam Boilers 42S/42S-A

61 7

93/193 20
63 8

94/194 22
64 10

764 12

150/157
67 14 150S/157S 24

767 16 1575 29

69 17
157S-RBP 28

1
Table of Contents

BoiLer ControL rePLaCement PartS (continued)

water FeederS For SerieS Page water FeederS For SerieS Page

• Electric Uni-Match® 31 • Make-Up 21 33

WF2 And WFE

25-A 34
101-A 32

221 35
• Mechanical 47/47-2 40

551-S 36
247/247-2 42

847 37
51/51-2 44

851 38

51-S/51-S-2 46
851-S 39

53/53-2 48

VaLVeS
• Test-N-Check® TC-4 50

2
Table of Contents

Liquid LeVeL ControL ProduCtS

remote SenSorS For SerieS Page FLoat aCtuated For SerieS Page

RS 51 27-W 53

PneumatiC aCtuated
PFC 52

FLow SwitCh ProduCtS

Liquid FLow For SerieS Page Liquid FLow For SerieS Page

• General Purpose FS4-3 55 • Industrial FS7-4 62

FS4-3-T 56 FS7-4E 63

FS5 57 FS7-4W 63

FS8-W 58

air FLow
FS-251 59
AF1 64

FS-254 59
AFE-1 65
• High Sensitivity FS1 60

AF2 66
FS1-W 60

AF3 67
FS6 61

FS6-W 61

3
 GENERAL INFORMATION LIQUID LEVEL CONTROLS FLOW SWITCHES BOILER CONTROLS

4
notes
Boiler Control Replacement Parts
Boiler Control Replacement Parts
Replacement Probes

BOILER CONTROLS
PA-800
For Repl. Probe Part Weight
Model Model No. Number Description lbs. (kg)

PS-801-120 PA-800 354081 Probe 0.5 (.23)

PSE-851-120 Dimensions, in. (mm)
PS-802-24 3/4 NPT
PS-852-24
RS-1-LP
PS-851-M-120
PS-852-M-24
PS-801-M-120 1.31 1.56 2.13
(33) (40) (54)
PS-802-M-24
750P-MT-120
751P-MT-120
751P-MT-24
PSE-801-120
PSE-802-24
PSE-801-M-120
PSE-802-M-24

PA-800-U
For Repl. Probe Part Weight
Model Model No. Number Description lbs. (kg)

PS-801-U-120 PA-800-U 354141 Probe 0.5 (.23)

PS-802-U-24 Dimensions, in. (mm)
PS-851-M-U-120 3/4 NPT
PS-851-U-120
PS-802-M-U-24
PS-801-M-U-120
750P-MT-U-120 1.31
(33) 3.06 1.56
PSE-801-M-U-120 (78) (40)
PSE-802-M-U-24
PSE-801-U-120
PSE-802-U-24
751P-MT-U-120
752P-MT-U-24

5
 Boiler Control Replacement Parts
Replacement Probes
BOILER CONTROLS

PA-800-RX2
For Repl. Probe Part Weight
Model Model No. Number Description lbs. (kg)

PS-802-RX2-24 PA-800-RX2 354140 Probe 0.5 (.23)

PS-851-RX2-120 Dimensions, in. (mm)

1/2 NPT
PSE-802-RX2-24

1.31 1.56 2.13

(33) (40) (54)

PA-RB-122

For Repl. Probe Part Weight

Model Model No. Number Description lbs. (kg)

RB-122 PA-RB-122 354083 Probe 0.5 (.23)

Dimensions, in. (mm)
RS-1-LP-S
3/4 NPT
PS-851-SP-120

PS-852-SP-24

RB-120

PS-851-M-SP-120 1.31 1.56 1.32

(33) (40) (34)
PS-852-M-SP-24

751P-MT-SP-120

752P-MT-SP-24

6
Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Steam Boilers

BOILER CONTROLS
Series 61
Low Water Cut-Offs

Series 61

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg)

61-HD 140300 Head mechanism 3.5 (1.6)

61 or
6667 153825 Head mechanism 1.5 (0.7)
Head mechanisms include a gasket and bolts.

Components model 61-hd

Part Catalog Weight

Key Number Number Description lbs. (kg)

1 302600 CO-12 Head Gasket 0.1 (0.5)

2 318800 67-12 Gasket 0.1 (0.5)
3 344200 SA67-2 Float & Bellows Assembly 0.3 (.14)
4 309100 11 Switch 0.5 (.23)
5 309151 11-M Switch w/Manual Reset 0.5 (.23)
6 309200 11-MV Switch for Millivolt Service 0.5 (.23)

model 6667

3 4 5 6

2
1

7
 Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Hot Water Boilers
BOILER CONTROLS

Series 63
Low Water Cut-Offs

Series 63

Replacement Head Mechanisms

For Repl. Head Part Weight
Model Model No. Number Description lbs. (kg)

63
63-HD 142600 Head mechanism 7.0 (3.2)
w/ No. 2 switch
63-B

63-BM
63-M-HD 143200 63-HD w/manual reset 7.0 (3.2) model 63-hd
63-M
Head mechanisms include a gasket and bolts.

Components (shown on page 9)

model 63-m-hd
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 110000 2 Switch 1.0 (0.5)

2 110100 2-M Switch w/manual reset 1.0 (0.5)

3 343200 SA63-5 Bellows assembly 1.5 (7.3)

4 302500 CO-11 Gasket 0.1 (.05)

5 343400 SA63-30 Float 1.0 (0.5)

6 302600 CO-12 Head gasket 0.1 (.05)

7 302900 CO-106 Cam 0.1 (.05)

8
Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Hot Water Boilers

BOILER CONTROLS
Series 63 (continued)
Low Water Cut-Offs
Components

1
2

4
5

9
 Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Hot Water Boilers
BOILER CONTROLS

Series 64
Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg)

64 64-HD 144400 Head mechanism 4.0 (1.8)

Series 64
64-A
Head mechanisms include a gasket and bolts.

Components (shown on page 11)

Item Part Model Weight
Number Number Number Description lbs. (kg)

1 343600 SA64-30 Float assembly 1.0 (0.5)

2 302600 CO-12 Head gasket 0.1 (.05)

3 343500 SA64-2 Bellows assembly 0.3 (.14)

(includes item 2) model 64-a

4 318800 67-12 Gasket 0.1 (.05)

5 309100 11 Switch 0.5 (.23)

6 309151 11-M No. 11 w/manual reset 0.5 (.23)

7 309200 11-MV No. 11 for Millivolt service 0.5 (.23)

8* 332800 MA-259 Quick hook-up fittings 4.5 (2.0)

(includes item 8, 9, 10)

9* 351800 SA259-24 Upper quick hook-up 1.7 (.77) model 64-hd

10* 349500 SA159-24 Lower quick hook-up 1.7 (.77)

11* 349400 SA159-17 Black “Y” assembly 2.3 (1.0)

*Available for 64-A models only

10
Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Hot Water Boilers

BOILER CONTROLS
Series 64 (continued)
Low Water Cut-Offs
Components

11
8 9

1 3 5 6 7

10

4
2

11
 Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Hot Water Boilers
BOILER CONTROLS

Series 764
Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg)

764 64-HD 144400 Head mechanism 4.0 (1.8)

Series 764
Head mechanisms include a gasket and bolts.

model 64-hd
Components (shown on page 13)
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 343600 SA64-30 Float assembly 1.0 (0.5)

2 302600 CO-12 Head gasket 0.1 (.05)

3 343500 SA64-2 Bellows assembly 0.3 (.14)

(includes item 2)

4 318800 67-12 Gasket 0.1 (.05)

5 309100 11 Switch 0.5 (.23)

6 309151 11-M No. 11 w/manual reset 0.5 (.23)

7 309200 11-MV No. 11 for Millivolt service 0.5 (.23)

12
Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Hot Water Boilers

BOILER CONTROLS
Series 764 (continued)
Low Water Cut-Offs
Components

1 3 5 6 7

4
2

13
 Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Steam Boilers
BOILER CONTROLS

Series 67
Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Model Model No. Number Description lbs. (kg)

67
Series 67
67-LQHU 6667 153825 Head mechanism 1.5 (0.7)

67-G 6667MV 153850 6667 for Millivolt 1.5 (0.7)

service

model 67-Lqhu
Components (shown on page 15) (without quick
hook-up fittings)
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 344100 SA66-35 Upper tube assembly 1.0 (0.5)

2 334600 MA559 Quick hook-up fittings 2.5 (1.1)

3 318800 67-12 Gasket 0.1 (.05)

4 344200 SA67-2 Float and bellows assembly 1.0 (0.5)

5 309100 11 Switch 0.5 (.23)

model 6667
6 309151 11-M Switch w/manual reset 0.5 (.23)

7 309200 11-MV No. 11 for Millivolt service 0.5 (.23)

8 310447 14-B Blow-down valve 0.5 (.23)

9 313200 37-39 Blow-down valve gasket 0.1 (.05)

model 6667mV

14
Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Steam Boilers

BOILER CONTROLS
Series 67 (continued)
Low Water Cut-Offs
Components

Model 6667
2

4 5 6 7

15
 Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Steam Boilers
BOILER CONTROLS

Series 767
Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Model Model No. Number Description lbs. (kg)
Series 767
767 6667 153825 Head mechanism 1.5 (0.7)

Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 318800 67-12 Gasket 0.1 (.05)

2 344200 SA67-2 Float and bellows assembly 1.0 (0.5)

model 6667
3 309100 11 Switch 0.5 (.23)

4 309151 11-M Switch w/manual reset 0.5 (.23)

5 309200 11-MV No. 11 w/Millivolt service 0.5 (.23)

6 310447 14-B Blow-down valve 0.5 (.23)

7 313200 37-39 Blow-down valve gasket 0.1 (.05)

Model 6667

2 3 4 5

16
Boiler Control Replacement Parts
Low Water Cut-Offs – Float Type
For Steam Boilers

BOILER CONTROLS
Series 69
Low Water Cut-Offs
Replacement Head Mechanisms
For Repl. Head Part Weight
Model Model No. Number Description lbs. (kg)

69

69-J
Series 69
169

269 6667 153825 Head mechanism 1.5 (0.7)

369

469

569

69-MV-P 6667-MV 153850 6667 w/Millivolt service 1.5 (0.7)

369-MV
Components model 6667

Item Part Model Weight

Number Number Number Description lbs. (kg)

1 344300 SA69-104 Shield assembly 0.5 (.23)

2 320500 69-112 Gasket (GT Models) 0.1 (.05)

3 318826 69-113 O-ring .01 (.004)

4 318827 69-114 O-ring .01 (.004)

5 318800 67-12 Gasket 0.1 (.05)

model 6667mV
6 309100 11 Switch 0.5 (.23)

7 309151 11-M Switch w/Manual Reset 0.5 (.23)

8 309200 11-MV Switch for Millivolt Service 0.5 (.23)

9 344200 SA67-2 Float & Bellows Assembly 0.1 (.05)

9 8 6 7
2 3
4

1 5
17
 Boiler Control Replacement Parts
Combination Low Water Cut-Off/Pump Controllers
For Steam Boilers
BOILER CONTROLS

Series 42 and 42S

Low Water Cut-Off/Pump Controllers

Series 42S

Replacement Head Mechanisms

For Repl. Head Part Weight
Model Model No. Number Description lbs. (kg)

42S 42S-HD 129502 Head mechanism 7.5 (3.4)

Head mechanisms include a gasket and bolts.

Components (shown on page 19)

Item Part Model Weight
Number Number Number Description lbs. (kg) model 42S-a

1 302600 CO-12 Head gasket 0.1 (.05)

2* 328300 MA-159 Quick hook-up fittings 6.0 (2.7)

(includes items 4, 5, 6)

3* 351800 SA259-24 Upper quick hook-up fittings 1.7 (.77)

4* 349500 SA159-24 Lower quick hook-up fittings 1.7 (.77)

5* 349400 SA159-17 Black “Y” assembly 3.0 (1.4)

model 42S-hd
6 347900 SA150-106R Bellows Assembly 0.4 (.18)
* Available for 42S-A models only.
IMPORTANT:
Replacement Switch Information • Snap switches must be replaced as an assembly.
• We recommend complete head replacement to eliminate the
need for field replacement of the switch assembly.
• Series 42 & 42S Replacement Switch Assemblies are not
interchangeable and must be selected and ordered for the
specific control model(s) on which they will be installed.

Replacement Switch Assemblies For Series 42S

For Repl. Switch Part Weight
Model Model No. Number Description lbs. (kg)

42S SWA-42S 310488 Snap-action 0.5 (.23)

switch assembly

model Swa-42S

18
Boiler Control Replacement Parts
Combination Low Water Cut-Off/Pump Controllers
For Steam Boilers

BOILER CONTROLS
Series 42 and 42S (continued)
Low Water Cut-Off/Pump Controllers
Components

5
3

19
 Boiler Control Replacement Parts
Combination Low Water Cut-Off/Pump Controllers
For Steam Boilers
BOILER CONTROLS

Series 93 & 193

Low Water Cut-Off/Pump Controllers
Replacement Head Mechanisms
For Part Repl. Head Weight
Model Number Model No. Description lbs. (kg)

93, 193 162400 93-HD Head mechanism 16 (7.25)

163200 93-7B-HD Head mechanism with 7B switch 16 (7.25)

162600 93-M-HD Head mechanism, manual reset 16 (7.25)

163300 93-7B-M-HD Head mechanism with 7B switch, 16 (7.25)

manual reset
Components (shown on page 21)
Item Part Model Weight Series 93-hd
Number Number Number Description lbs. (kg)

1 162402 93-HDLS Head w/o switch 15.0 (6.8)

2 345700 SA91-60 Float (includes item 3) 0.7 (.32)

3 325400 150-14 Gasket 0.1 (.05)

4 110300 5 Electric switch 3.5 (1.6)

5 110400 5-M No. 5 w/manual reset 3.5 (1.6)

6 110800 7B Electric switch/ 4.0 (1.8)

proportioning control
Series 93
7 110900 7B-M No. 7B w/manual reset 4.0 (1.8)

#5 Switch
1 344800 SA91-30B Burner Switch 0.1 (.05)
Contact Assembly
(Red dot on terminal panel)
(Includes 1A terminal panel)
2 345000 SA91-30P Pump Switch 0.1 (.05)
Contact Assembly
(Blue dot on terminal panel)
(Includes 2A terminal panel)

#7B Switch Series 193

1 344800 SA91-30B Burner Switch 0.1 (.05)
Contact Assembly
(Red dot on terminal panel)
(Includes 1A terminal panel)
2 309000 7B-1R Resistor/Slide 0.1 (.05)
Wire Assembly
3 345150 SA7-30 Terminal Panel 0.5 (.23)

20
Boiler Control Replacement Parts
Combination Low Water Cut-Off/ – Pump Controllers
For Steam Boilers

BOILER CONTROLS
Series 93 & 193 (continued)
Low Water Cut-Off/Pump Controllers
Components
4 5 6 7

1A 3

3
2
2

7B Switch

1A 2A

1 2

5 Switch

21
 Boiler Control Replacement Parts
Combination Low Water Cut-Off/Pump Controllers
For Steam Boilers
BOILER CONTROLS

Series 94 & 194

Low Water Cut-Off/Pump Controllers
Replacement Head Mechanisms
For Part Repl. Head Weight
Model Number Model No. Description lbs. (kg)

94, 194 165300 94-HD Head mechanism 21 (9.52)

166000 94-M-HD Head mechanism, manual reset 21 (9.52)

166400 94-7B-HD Head mechanism with 7B switch 21 (9.52)

166500 94-7B-M-HD Head mechanism with 7B switch, 21 (9.52)

manual reset Series 94-hd

Components (shown on page 23)

Item Part Model Weight
Number Number Number Description lbs. (kg)

1 165302 94-HDLS Head w/o switch 15.0 (6.8)

2 345700 SA91-60 Float (includes item 3) 0.7 (.32)

3 323300 92-68 Gasket 0.1 (.05)

4 110300 5 Electric switch 3.5 (1.6)

5 110400 5-M No. 5 w/manual reset 3.5 (1.6)

6 110800 7B Electric switch/ 4.0 (1.8) Series 94

proportioning control

7 110900 7B-M No. 7B w/manual reset 4.0 (1.8)

#5 Switch
1 344800 SA91-30B Burner Switch 0.1 (.05)
Contact Assembly
(Red dot on terminal panel)
(Includes 1A terminal panel)
2 345000 SA91-30P Pump Switch 0.1 (.05)
Contact Assembly
(Blue dot on terminal panel)
(Includes 2A terminal panel)
#7B Switch
1 344800 SA91-30B Burner Switch 0.1 (.05) Series 194
Contact Assembly
(Red dot on terminal panel)
(Includes 1A terminal panel)
2 309000 7B-1R Resistor/Slide 0.1 (.05)
Wire Assembly
3 345150 SA7-30 Terminal Panel 0.5 (.23)

22
Boiler Control Replacement Parts
Combination Low Water Cut-Off/ – Pump Controllers
For Steam Boilers

BOILER CONTROLS
Series 94 & 194 (continued)
Low Water Cut-Off/Pump Controllers

4 5 6 7

1A 3

3
2 2

7B Switch

1A 2A

1 2

5 Switch

23
 Boiler Control Replacement Parts
Low Water Cut-Off/Pump
Controllers For Steam Boilers
BOILER CONTROLS

Series 150, 150S

Series 157, 157S
The Series 150S is available as an alternative for
Series 150 LWCO controls that contain mercury
switches. Please keep in mind that in a replacement
or repair situation you do not have to change out the 150 or 150S 157 or 157S
entire control. A head replacement (i.e. 150S-HD) is Float Chamber Body water Column Body
all that’s required.

There may be additional letters such as ‘B’, ‘R’, ‘RL’,

etc. in the sales catalog designation of the control.
These additional letters designate tapping locations
and sizes which have no affect on which head
mechanism to purchase. All head mechanisms are
interchangeable and can be installed on any body.

‘MD’Models
The ‘MD’ model should be used as a replacement
head when the boiler operating pressure is less than
50 psi. These were created to provide a control with
factory settings to compensate for the narrowing of
setpoints. The larger differential between pump on
and burner off reduces the potential for nuisance
burner shutdown.

It is important to understand that there are

requirements that lead to the best performance
of ALL level controllers and LWCO’s:

• Use of properly-sized pump starters/relays

in the pump control circuitry
• Pumps that are balanced to the system
requirements
• Equalizing piping, per the boiler manufacturer’s
recommendations, to properly sense the
boiler water level
• Industry accepted blowdown piping to provide
best cleaning action of the control chamber, float
linkage mechanism and/or probes
• Proper periodic blowdown of the boiler controls.
• Proper chemical treatment of boiler water.
• Annually cleaning and careful exam-
ination of the float mechanism, probes, and
electrical switches or controls. More frequent
cleaning may be required for exceptionally
dirty steam systems.

24
Boiler Control Replacement Parts
Low Water Cut-Off/Pump Controllers
For Steam Boilers

BOILER CONTROLS
Series 150, 150S
Series 157, 157S
(continued)

Replacement Head Mechanisms

For Part Repl. Head Weight
Model Number Model No. Description lbs. (kg)

150S-HD 173003 Head mechanism 11.0 (5.0)

150S-M-HD 172809 150S-HD w/manual reset 11.0 (5.0)

150S-MD-HD 173103 150S-HD w/maximum differential 11.0 (5.0)

150S-M-MD-HD 172810 150S-HD w/manual reset 11.0 (5.0)

and maximum differential

158S-HD 178602 Head mechanism 12.5 (5.7) Series 150S-hd

158S-M-HD 172821 158-S-HD w/manual reset 12.5 (5.7)

158S-M-MD-HD 172822 158-S-HD w/manual reset 12.5 (5.7)

and maximum differential

159S-HD 172702 Head mechanism 12.0 (5.7)

25
 Boiler Control Replacement Parts
Low Water Cut-Off/Pump Controllers
BOILER CONTROLS

For Steam Boilers

Series 150, 150S
Series 157, 157S

IMPORTANT:
• Snap switches must be replaced as an assembly.
• We recommend complete head replacement to eliminate the need for field adjustment
of the switch assembly.
• Series 150S and 157S replacement switch assemblies are not interchangeable with
Series 150 and 157 mercury switch controls.

Note:
Manual reset models with date code 03K (October 2003)
or older require the purchase of a new head.

Replacement Switch Assemblies for Series150S and 157S

For Repl. Switch Part Weight
Model Model No. Number Description lbs. (kg)

All SWA-150S 310462 Snap-action 0.5 (.23)

150S & 157S switch assembly
Units model Swa-150S
Except SWA-150S-M 354089 Snap-action 0.5 (.23) model Swa-150S-md
‘MD’ Models switch assembly model Swa-150S-m
w/manual reset model Swa-150S-m-md

All SWA-150S-MD 310464 Snap-action switch 0.5 (.23)

150S & 157S assembly for maximum
‘MD’ Models differential models

SWA-150S-M-MD 354086 Snap-action switch 0.5 (.23)

assembly for maximum
differential models
w/manual reset
model Swa-158S
model Swa-158S-m

All SWA-158S 310468 Snap-action 0.5 (.23)

158S switch assembly
Models for Model 158S

SWA-158S-M 354087 Snap-action 0.5 (.23)

switch assembly
w/manual reset

All
159S SWA-159S 310470 Snap-action 0.5 (.23)
Models switch assembly
model Swa-159S

Switch assemblies include a mounting bracket and color-coded terminal connection wires.

26
Boiler Control Replacement Parts
Low Water Cut-Off/Pump Controllers

BOILER CONTROLS
For Steam Boilers
Series 150, 150S
Series 157, 157S (continued)

7
Series 150 Head Gasket
and Casting

Refer to page 26 for RAISED

Switch Assemblies FLANGE GASKET

R
3 CATALOGUE NO.
150-14H
P.N. 325500

RAISED FLANGE

This new gasket, specifically designed for

the Raised Flange Heads, may be used.

FLAT
FLANGE GASKET
4 CATALOGUE NO.
150-14
2 P.N. 325400

FLAT FLANGE

This gasket must be used on the Flat

Flange Heads.

Series 150S

Components
Item Model Part Weight
Number Number Number Description lbs. (kg)

1 SA150-106R 347900 Bellows assembly 0.4 (.18)

2 SA150-11 347600 Float & rod 1.0 (0.5)

3 150-14H 325500 Head gasket for raised 0.5 (.23)

face flange head, 8 holes

4 150-14 325400 Head gasket for flat 0.5 (.23)

face flange head, no holes

7 150-436 326950 Cover .435 (.19)

27
 Boiler Control Replacement Parts
Low Water Cut-Off/Pump Controllers
For Steam Boilers
BOILER CONTROLS

Series 150, 150S

Series 157, 157S (continued)

2
1

Components
Item Model Part Weight
Number Number Number Description lbs. (kg)

1 EA-157-S 354106 Short electrode for 157S-RBP 0.5 (.23)

2 EA-157-L 354107 Long electrode for 157S-RBP 0.5 (.23)

model 157S-rBP

28
Boiler Control Replacement Parts
Low Water Cut-Off/Pump Controllers
For Steam Boilers

BOILER CONTROLS
Series 1575

Components
Item Model Part Weight
Number Number Number Description lbs. (kg)
1
1 150E-CU 310490 Control unit, automatic reset 2.07 (.96)

2 PA-750-HP 176319 High Pressure Probe 0.5 (0.23)

3 PS-1-SS 179530 Sensing Probe Rod-12" 0.5 (0.23)

29
 BOILER CONTROLS

30
notes
Notes
Boiler Control Replacement Parts
Water Feeders – Electric

BOILER CONTROLS
Series wF2 and wFe uni-match®
Electric Water Feeders

Components
Item Part Model Weight uni-match®
Number Number Number Description lbs. (kg)

1 310473 STR-WF2 Strainer/orifice kit 0.1 (.05)

31
 Boiler Control Replacement Parts
Water Feeders – Electric
BOILER CONTROLS

Series 101-a
Electric Water Feeders

Components
Item Part Model Weight
Number Number Number Description lbs. (kg) Series 101-a

1 310453 CTRD-101 Cartridge & strainer kit 0.8 (.36)

2 324435 37-101 Tetraseal O-ring 0.1 (.05)

3 324100 101-24V-48 Transformer (24V) 3.5 (1.6)

4 347100 SA-101-38 Strainer (includes item 2) 0.7 (.32)

1
4
3

Round Port Hex Port

Pilot Action Style Cartridge Style
Before August 1995 After August 1995

32
Boiler Control Replacement Parts
Water Feeders – Make-Up

BOILER CONTROLS
Series 21
Make-Up Water Feeders
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 311200 21-30 Float 1.7 (.77)

(includes item 2)
Series 21
2 335400 847-26 Gasket 0.1 (.05)

3 311100 21-27 Gasket 0.1 (.05)

4 310800 21-12 Gasket 0.1 (.05)

5 339500 SA21-6 Valve assembly 3.0 (1.4)

(includes items 2, 3, 4 & 6)

6 312900 37-28 Gasket 0.1 (.05)

7 342300 SA51-9R Strainer assembly 3.0 (1.4)

8 339700 SA21-38R Strainer basket 1.0 (0.5)

(includes item 9)

9 324435 37-101 Tetraseal O-ring 0.1 (.05)

10 311400 21-109 Connector 0.1 (.05)

11 310600 21-3 Bracket 2.5 (1.1)

11
10 3

2 4

7
9

33
 Boiler Control Replacement Parts
Water Feeders – Make-Up
BOILER CONTROLS

Series 25-a
Make-Up Water Feeders

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg)

25-A 25A-HD 127100 Head mechanism 20 (9.1)

Components Series 25-a

Item Part Model Weight

Number Number Number Description lbs. (kg)

1 304100 F-26 Gasket 0.1 (.05)

2 334100 421-30 Float 1.5 (0.7)
(includes item 2)
3 340400 SA27T-75 Diaphragm seal assembly 0.1 (.05)
(includes item 1)
4 339800 SA25-5 Arm assembly 0.1 (.05)
5 311100 21-27 Gasket 0.1 (.05)
6 312900 37-28 Gasket 0.1 (.05)
7 342300 SA51-9R Strainer assembly 3.0 (1.4)
model 25-a-hd
(includes item 6)
8 324435 37-101 Tetraseal O-ring 0.1 (.05)
9 339700 SA21-38R Strainer basket 1.0 (0.5)
(includes item 8)
10 339900 SA25A-6 Valve assembly 3.0 (1.4)
11 340000 SA25A-15 Stem, disc & seat assembly 0.3 (.14)
` (includes item 6)
12 311900 27T-9 Float Rod 0.1 (.05)

4 5
12

1 2
3
10
6

11

8 7

34
Boiler Control Replacement Parts
Water Feeders – Make-Up

BOILER CONTROLS
Series 221
Make-Up Water Feeders
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 311200 21-30 Float 1.7 (.77)

(includes item 2)
Series 221
2 304100 F-26 Gasket 0.1 (.05)
3 311100 21-27 Gasket 0.1 (.05)
4 310800 21-12 Gasket 0.1 (.05)
5 339500 SA21-6 Valve assembly 3.0 (1.4)
(includes 2,3,4,6)
6 312900 37-28 Gasket 0.1 (.05)
7 342300 SA51-9R Strainer assembly 3.0 (1.4)
8 339700 SA21-38R Strainer basket 1.0 (0.5)
(includes item 9)
9 324435 37-101 Tetraseal O-ring 0.1 (.05)
10 311400 21-109 Connector 0.1 (.05)
11 310600 21-3 Bracket 2.5 (1.1)

10
3 11

4
2

7
9

35
 Boiler Control Replacement Parts
Water Feeders – Make-Up
BOILER CONTROLS

Series 551-S
Make-Up Water Feeders
Replacement Head Mechanisms
For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg)

551-S 551S-HD 136600 Head mechanism 25.7 (11.7)

Components Series 551-S

Item Part Model Weight
Number Number Number Description lbs. (kg)

1 310437 FLT-51-05 Float (includes item 2) 2.5 (1.1)

(see note below)

2 304100 F-26 Gasket 0.1 (.05)

3 310442 BA-551-05 Bellows bracket assembly 1.5 (0.7)

(see note below)

4 312800 37-27 Gasket 0.1 (.05)

Series 551-S-hd
5* 352600 SA551S-101-102 Valve & strainer kit 4.0 (1.8)

6 324435 37-101 Tetraseal o-ring 0.1 (.05)

7 347100 SA101-38 Strainer basket 0.7 (.32)

(includes item 6)

8 310452 CTRD-51 Cartridge kit 0.8 (.36)

1 NOTE:
2 One time float and bellows
replacement is required
4 when replacing bellows or
float assemblies with date
codes before February 2005
(05B).
4

6
Round Boss Hex Boss 5
Pilot Action Style Cartridge Style
Pre August 1995 After August 1995
8
7
* Units manufactured prior to August 1995 have a round
port pilot valve and a strainer assembly. These valve
and strainer assemblies can be replaced with the
current hex port cartridge valve and strainer assembly.

36
Boiler Control Replacement Parts
Water Feeders – Make-Up

BOILER CONTROLS
Series 847
Make-Up Water Feeders
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 313600 37A-130 Float (includes item 2) 2.0 (0.9)

2 335400 847-26 Gasket 0.1 (.05)

Series 847
3 352800 SA847-4 Bellows bracket assembly 1.5 (0.7)
(includes item 2 and 4)

4 312800 37-27 Gasket 0.1 (.05)

5* 341600 SA47-101-102 Valve & strainer kit 3.0 (1.4)

6 324435 37-101 Tetraseal O-ring 0.1 (.05)

7 347100 SA101-38 Strainer basket 0.7 (.32)

(includes item 6)

8 310453 CTRD-101 Cartridge & strainer kit 0.8 (.36)

9 110000 2 Switch 1.0 (0.5)

10 312600 37-20 Cover 0.1 (.05)

2
1

10

4 4 9

6
Round Boss Hex Boss
5
Pilot Action Style Cartridge Style
Pre August 1995 After August 1995
8
7
* Units manufactured prior to August 1995 have a round
port pilot valve and a strainer assembly. These valve
and strainer assemblies can be replaced with the
current hex port cartridge valve and strainer assembly.

37
 Boiler Control Replacement Parts
Water Feeders – Make-Up
BOILER CONTROLS

Series 851
Make-Up Water Feeders
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 313600 37A-130 Float (includes item 2) 2.0 (0.9)

2 335400 847-26 Gasket 0.1 (.05)

Series 851
3 352925 SA851-4 Bellows bracket assembly 1.5 (0.7)

4 312800 37-27 Gasket 0.1 (.05)

5* 342500 SA51-101-102 Valve & strainer kit 3.0 (1.4)

6 324435 37-101 Tetraseal O-ring 0.1 (.05)

7 347100 SA101-38 Strainer basket 0.7 (.32)

(includes item 6)

8 310452 CTRD-51 Cartridge & strainer kit 0.8 (.36)

9 335700 851-105 Float rod 0.3 (.14)

10 110000 2 Switch 1.0 (.05)

11 312600 37-20 Cover 0.1 (.05)

2
1

9 11

4 4
10

6
Round Boss Hex Boss 5
Pilot Action Style Cartridge Style
Pre August 1995 After August 1995
8 7
* Units manufactured prior to August 1995 have a round
port pilot valve and a strainer assembly. These valve
and strainer assemblies can be replaced with the
current hex port cartridge valve and strainer assembly.

38
Boiler Control Replacement Parts
Water Feeders – Make-Up

BOILER CONTROLS
Series 851-S
Make-Up Water Feeders
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 313600 37A-130 Float (includes item 2) 2.0 (.9)

2 335400 847-26 Gasket 0.1 (.05)

Series 851-S
3 352925 SA851-4 Bellows bracket assembly 1.5 (.7)
(includes item 4)

4 312800 37-27 Gasket 0.1 (.05)

5 342100 SA51S-6 Valve assembly 3.0 (1.4)

6 316200 51S-114 Valve seat 0.1 (.05)

7 312900 37-28 Gasket 0.1 (.05)

8 324435 37-101 Tetraseal O-ring 0.1 (.05)

9 340700 SA37-38 Strainer basket 0.7 (.32)

(includes item 8))

10 342200 SA51-9 Strainer assembly 3.0 (1.4)

11 335750 851S-105 Float rod 0.3 (.14)

12 110000 2 Switch 1.0 (0.5)

13 312600 37-20 Cover 0.1 (0.5)

2
1
11 13

4 4
12

5
6
7

8
10

39
 Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs
BOILER CONTROLS

Series 47/47-2
Mechanical Water Feeder/Low Water Cut-Offs
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)
Series 47
1 310453 CTRD-101 Cartridge and strainer kit .35 (.16)

2* 341600 SA47-101-102 Valve, cartridge & strainer 3.0 (1.4)

assembly kit

3 324435 37-101 Tetraseal o-ring 0.1 (.05)

4 347100 SA101-38 Strainer for hex port valves 0.7 (.32)

(includes item 3)

5 341500 SA47-4 Bellows and bracket assembly 1.5 (0.7)

(includes item 15)

6 312800 37-27 Gasket 0.1 (.05) Series 47-2

7 302900 CO-106 Cam assembly 0.1 (.05)

8 110000 2 Switch 1.0 (0.5)

9 110100 2-M Switch with manual reset 1.0 (0.5)

10 332800 MA-259 Quick hook-up fittings 4.5 (2.0)

(includes item 11, 12, 13)

11 349400 SA159-17 Black “Y” assembly 2.3 (1.0)

12 351800 SA259-24 Upper quick hook-up fittings 1.7 (.77)

13 349500 SA159-24 Lower quick hook-up fittings 1.7 (.77)

14 340600 SA37-30 Float assembly 2.0 (0.9)

15 312700 37-26 Gasket 0.1 (.05)

16 310447 14-B Blow-down valve 1.5 (0.7)

(includes item 17)

17 313200 37-39 Blow-down valve gasket 1.0 (0.5)

* Units manufactured prior to August 1995

have a round port pilot valve and a strainer
assembly. These valve and strainer
assemblies can be replaced with the
current hex port cartridge valve and
strainer assembly.
Round Port Hex Port
Pilot Action Style Cartridge Style
Before August 1995 After August 1995

40
Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs

BOILER CONTROLS
Series 47/47-2 (continued)
Mechanical Water Feeder/Low Water Cut-Offs
Components

11

12 8
9
7

6
6
10

5
14
15
13

3
2

1 4

17

16

41
 Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs
BOILER CONTROLS

Series 247/247-2
Mechanical Water Feeder/Low Water Cut-Offs
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)
Series 247
1 310453 CTRD-101 Cartridge & strainer kit .35 (.16)

2* 341600 SA47-101-102 Valve, cartridge & strainer 3.0 (1.4)

assembly kit

3 324435 37-101 Tetraseal o-ring 0.1 (.05)

4 347100 SA101-38 Strainer for hex port valves 0.2 (.09)

(includes item 3)

5 341900 SA47-104 Bellows & bracket assembly 1.5 (0.7)

(includes item 11)

6 312800 37-27 Gasket 0.1 (.05) Series 247-2

7 302900 CO-106 Cam assembly 0.1 (.05)

8 110000 2 Switch 1.0 (0.5)

9 110100 2-M Switch w/manual reset 1.0 (0.5)

10 340600 SA37-30 Float assembly 2.0 (0.9)

11 312700 37-26 Gasket 0.1 (.05)

Round Boss Hex Boss

Pilot Action Style Cartridge Style
Pre August 1995 After August 1995

* Units manufactured prior to August 1995 have a round

port pilot valve and a strainer assembly. These valve
and strainer assemblies can be replaced with the
current hex port cartridge valve and strainer assembly.

42
Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs

BOILER CONTROLS
Series 247/247-2 (continued)
Mechanical Water Feeder/Low Water Cut-Offs
Components

8
9

6
6

5
10

11

3
2

1 4

43
 Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs
BOILER CONTROLS

Series 51/51-2
Water Feeder/Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg) Series 51

51-2-HD 135100 Head mechanism w/ No. 2 switch 18.3 (8.3)

51-2 or
51-2M-HD 135300 51-2-HD w/manual reset 26.0 (11.8)

Components (shown on page 43)

Item Part Model

1 110000 2 Low water cut-off switch 1.0 (0.5)

Series 51-2
2 110100 2-M No. 2 w/manual reset 1.0 (0.5)

3 310437 FLT-51-05 Float 2.5 (1.1)

(see note following page)

4 304100 F-26 Gasket 0.1 (.05)

5 312800 37-27 Gasket 0.1 (.05)

6 302900 CO-106 Cam assembly 0.1 (.05)

7 310439 BA-51-05 Bellows bracket assembly 1.5 (0.7)

(includes item 4)
(see note following page) model 51-2-hd

8* 342500 SA51-101-102 Valve & strainer kit 3.0 (1.4)

9 310452 CTRD-51 Cartridge & strainer kit 0.8 (.36)

10 324435 37-101 Tetraseal O-ring 0.1 (.05)

11 347100 SA101-38 Strainer basket 0.7 (.32)

(includes item 10)

44
Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs

BOILER CONTROLS
Series 51/51-2 (continued)
Water Feeder/Low Water Cut-Offs
Components

1
2

4
6

8 10

9
Round Boss Hex Boss 11
Pilot Action Style Cartridge Style
Pre August 1995 After August 1995

* Units manufactured prior to August 1995 have a round

port pilot valve and a strainer assembly. These valve
and strainer assemblies can be replaced with the
current hex port cartridge valve and strainer assembly.

Note: One time float and bellows replacement is required when replacing
bellows or float assemblies with date codes before February, 2005 (05B).

45
 Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs
BOILER CONTROLS

Series 51-S/51-S-2
Water Feeder/Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg) Series 51-S

51-S-2-HD 136200 Head mechanism w/ No. 2 switch 20.5 (9.3)

51-S or
51-S-2M-HD 136250 51-S-2-HD w/manual reset 21.7 (9.8)

Components (shown on page 47)

Item Part Model Weight
Number Number Number Description lbs. (kg)

1 110000 2 Low water cut-off switch 1.0 (0.5)

Series 51-S-2
2 110100 2-M No. 2 w/manual reset 1.0 (0.5)

3 310437 FLT-51-05 Float 2.5 (1.1)

(see note following page)

4 304100 F-26 Gasket 0.1 (.05)

5 312800 37-27 Gasket 0.1 (.05)

6 302900 CO-106 Cam assembly 0.1 (.05)

7 310439 BA-51-05 Bellows bracket assembly 1.0. (0.7)

(includes item 4)
(see note following page) model 51-S-2-hd

8 342100 SA51S-6 Valve assembly 3.0 (1.4)

9 316200 51S-114 Valve seat 0.8 (.36)

10 342200 SA51-9 Strainer assembly 0.1 (.05)

11 312900 37-28 Gasket 0.1 (.05)

12 324435 37-101 Tetraseal O-ring 0.1 (.05)

13 340700 SA37-38 Strainer basket 0.7 (.32)

(includes item 12)
model 51-S-2m-hd

46
Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs

BOILER CONTROLS
Series 51-S/51-S-2 (continued)
Water Feeder/Low Water Cut-Offs
Components

1
2

8
9
11

12
10

13

Note: One time float and bellows replacement is required when replacing
bellows or float assemblies with date codes before February, 2005 (05B).

47
 Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs
BOILER CONTROLS

Series 53/53-2
Water Feeder/Low Water Cut-Offs

Replacement Head Mechanisms

For Repl. Head Part Weight
Series Model No. Number Description lbs. (kg) Series 53

53-2-HD 137300 Head mechanism w/ No. 2 switch 20.5 (9.3)

53 or
53-2M-HD 137250 53-2-HD w/manual reset 20.5 (9.3)

Components (shown on page 49)

Item Part Model Weight
Number Number Number Description lbs. (kg)

1 110000 2 Low water cut-off switch 1.0 (0.5) Series 53-2

2 110100 2-M No. 2 w/manual reset 1.0 (0.5)

3 304100 F-26 Gasket 0.1 (.05)

4 310438 FLT-53-05 Float 4.0 (1.8)

(See note following page)

5 302900 CO-106 Cam assembly 0.1 (.05)

6 312800 37-27 Gasket 0.1 (.05)

7 310441 BA-53-05 Bellows bracket assembly 1.5 (0.7)

(includes item 3)
model 53-2-hd
(See note following page)

8 342800 SA53-6 Valve assembly 3.0 (1.4)

9 312900 37-28 Gasket 0.1 (.05)

10 324435 37-101 Tetraseal O-ring 0.1 (.05)

11 340700 SA37-38 Strainer basket 0.7 (.32)

model 53-2m-hd

48
Boiler Control Replacement Parts
Combination Mechanical Water Feeder/
Low Water Cut-Offs

BOILER CONTROLS
Series 53/53-2 (continued)
Water Feeder/Low Water Cut-Offs
Components

1
2

4
8

10

11

Note: One time float and bellows replacement is required when replacing
bellows or float assemblies with date codes before February, 2005 (05B).

49
 Boiler Control Replacement Parts
Valves
BOILER CONTROLS

Series tC-4 test-n-Check®

Valves

Components
Series tC-4
Item Part Model Weight upper Valve
Number Number Number Description lbs. (kg)

1 317354 TC-V Vacuum breaker w/gasket 0.3 (.14)

2 317350 TC-U Upper valve (includes item 1) 2.7 (1.2)

3 317353 TC-L Lower valve 2.7 (1.2)

Series tC-4
Lower Valve

50
Liquid Level Control Replacement Parts

Probe Type Remote Sensors

Components for Remote Sensors

Item Part Model Weight
Number Number Number Description lbs. (kg)

1 354370 GSKT-RS-1 Cover gasket 0.3 (.14)

remote Sensor
model rS-1-Br-1
2 354401 EA-RS Electrode 0.5 (.23)

3 354081 PA-800 Probe 0.5 (.23)

4 354410 GSKT-RS-2 Cover gasket 0.3 (.14)

remote Sensor
model rS-1-LP

LIQUID LEVEL CONTROLS

remote Sensor
Series rS

4
2

2
1

Series rS model rS-1-LP model rS-1-Br-1

51
 Liquid Level Control Replacement Parts

Pneumatic Actuated

Series PFC
Liquid Level Controls
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 310471 SWA-PFC-D Valve assembly-DA 2.0 (0.9)

2 310472 SWA-PFC-R Valve assembly-RA 2.0 (0.9)

Series PFC
3 354411 G-PFC-S Supply gauge 0.3 (.14)

4 354412 G-PFC-O Output gauge 0.3 (.14)

5 354320 FLT-PFC Float (includes item 6) 0.5 (.23)

6 354310 GSKT-PFC Gasket 0.2 (.09)

1
2
LIQUID LEVEL CONTROLS

52
Liquid Level Control Replacement Parts

Float Actuated

Series 27-w
Liquid Level Controls

Components
Item Part Model Weight Series 27-w
Number Number Number Description lbs. (kg)

1 334100 421-30 Float & Nipple 1.5 (0.7)

(includes item 2)

2 311100 21-27 Gasket 0.1 (.05)

3 340100 SA27W-6 Valve assembly 3.5 (1.6)

(includes item 2)

LIQUID LEVEL CONTROLS

1

53
 Notes

notes

54
Flow Switch Replacement Parts
Flow Switches – Liquid

Series FS4-3
General Purpose Liquid Flow Switches
Components
For Item Part Model Weight
Model Number Number Number Description lbs. (kg)

All models
(except those below)
1 310451 FS4-15SS Stainless steel paddle kit 0.1 (.05) Series FS4-3

2 305200 FS4-33 SPDT switch 0.3 (.14)

3 305512 FS4-3D-17 SPDT switch 0.3 (.14)

FLOW SWITCHES
FS4-3D
4 304300 FS1-17 SPDT switch (next to 0.3 (.14)
adjustment screw)
Note: Paddle kits include screws and washers.

COMM
ON
1" 2" 3" 6"
3
NORM

NORM SED
CLO

OPEN
CO RM
NO

4
M
M
ON
OP
EN
NO SED
CL

RM
O

(25mm)
2 (51mm)
1
(76mm)

(152mm)

FLO
W

Series FS4-3 Series FS4-3d Paddle Kit

55
 Flow Switch Replacement Parts
Flow Switches – Liquid

Series FS4-3t
General Purpose Liquid Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 305200 FS4-33 SPDT switch 0.3 (.14)

2 336900 FS4-3T-25 Paddle kit 0.1 (.05)

Series FS4-3t
(includes O-ring)
Note: Paddle kits include screws and washers.
FLOW SWITCHES

FLO
W 1" 1" 1/2"

(25mm) (25mm) (15mm)

For Model For Model For Model
FS4-3T1 FS4-3T3 FS4-3T2
FS4-3T2
FS4-3T3

Paddle Kit

FS4-3t

56
Flow Switch Replacement Parts
Flow Switches – Liquid

Series FS5
General Purpose Liquid Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 304300 FS1-17 Switch 0.3 (.14)

Series FS5

FLOW SWITCHES
1

Series FS5

57
 Flow Switch Replacement Parts
Series FS8-w
General Purpose Liquid Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 307400 GSKT-FS8W O-ring 0.1 (.05)

2 310478 FS8-33 Switch 0.3 (.14)

Series FS8-w
3 310451 FS4-15SS Stainless steel paddle kit 0.1 (.05)

Note: Paddle kits include screws and washers.

FLOW SWITCHES

1 1" 2" 3" 6"

2
(25mm)
(51mm)
(76mm) 3

(152mm)

Series FS8-w Paddle Kit

58
Flow Switch Replacement Parts
Series FS250
General Purpose Liquid Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 310801 GSKT-FS254 O-Ring 0.1 (.05)

2 310802 SW-FS250 Switch 0.3 (0.14)

FS251
3 310451 FS4-15SS Stainless steel paddle kit 0.1 (.05)

Note: Paddle kits include screws and washers.

FLOW SWITCHES
FS254

1" 2" 3" 6"

(25mm)
(51mm)
(76mm) 3

(152mm)

FS251 FS254 Paddle Kit

59
 Flow Switch Replacement Parts
Flow Switches – Liquid

Series FS1 & FS1-w

High Sensitivity Liquid Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 300311 GSKT-FS1/6W O-ring 0.1 (.05)

2 304300 FS1-17 Switch 0.3 (.14)

Series FS1
FLOW SWITCHES

Series FS1-w
1
2
2

Series FS1 Series FS1-w

60
Flow Switch Replacement Parts

Flow Switches – Liquid

Series FS6 & FS6-w

High Sensitivity Liquid Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 300311 GSKT-FS1/6W O-ring 0.1 (.05)

2 304300 FS1-17 Switch 0.3 (.14)

Series FS6

FLOW SWITCHES
Series FS6-w

1
2
2

Series FS6 Series FS6-w

61
 Flow Switch Replacement Parts
Flow Switches – Liquid

Series FS7-4, FS7-4L & FS7-4S

Industrial Liquid Flow Switches
Components
For Item Part Model Weight
Series Number Number Number Description lbs. (kg)

FS7-4

FS7-4S 1 307000 FS7-31 SPDT switch 0.3 (.14)

Series FS7-4
FS7-4L

FS7-4
FLOW SWITCHES

2 337550 FS7S-4R-4 Paddle arm 0.5 (.23)

FS7-4S

FS7-4 3 306700 FS7-28 Bronze paddle kit 0.1 (.05)

FS7-4S 4 306800 FS7-28S Stainless steel paddle kit 0.1 (.05)

FS7-4L 5* 337900 FS7-28L Bronze paddle kit 0.1 (.05)

FS7-4L 6* 337650 FS7-VL-4R-4 Paddle arm 0.5 (.23)

Series FS7-4L
Note: Paddle kits include screws and washers.
* Available on L models only.

5
1
3 4

1" 6"

(25mm)

2
6
(152mm)

12"
Series FS7-4 & FS7-4S Paddle (305mm)
Series FS7-4, FS7-4L & FS7-4S Kit Series FS7-4L Paddle Kit

62
Flow Switch Replacement Parts
Flow Switches – Liquid

Series FS7-4e & FS7-4w

Industrial Liquid Flow Switches
Components
For Item Part Model Weight
Series Number Number Number Description lbs. (kg)

1 307000 FS7-31 SPDT switch 0.3 (.14)

All models
2 337550 FS7S-4R-4 Paddle arm 0.4 (.18)
Series FS7-4e & FS7-4w

FS7-4E
3 306700 FS7-28 Bronze paddle kit 0.1 (.05)
FS7-4W

FLOW SWITCHES
FS7-4SE
4 306800 FS7-28S Stainless steel paddle kit 0.1 (.05)
FS7-4SW

FS7-4W
5 307200 FS7-W-43 Gasket 0.1 (.05)
FS7-4SW
Note: Paddle kits include screws and washers.

1 1

3 4
5
1" 6"

(25mm)

2 (152mm)

Series FS7-4e Series FS7-4w Paddle Kit

63
 Flow Switch Replacement Parts
Flow Switches – Air

Series aF1
Air Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 307000 FS7-31 SPDT switch 0.3 (.14)

2 301200 AF1-21 Gasket 0.1 (.05)

Series aF1
3 336000 AF1-122 Paddle kit for model AF1 & AF1-J 0.1 (.05)
(includes item 2)
FLOW SWITCHES

4 336050 AF1-S-122 Paddle kit for model AF1-S 0.1 (.05)

(includes item 2)

Note: Paddle kits include screws and washers.

3
4

64
Flow Switch Replacement Parts
Flow Switches – Air

Series aFe-1
Air Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 304300 FS1-17 SPDT switch 0.3 (.14)

2 308300 AFE-1-122 Paddle kit 0.1 (.05)

Series aFe-1
(includes item 3)

3 317352 AFE-1-21 Gasket 0.1 (.05)

FLOW SWITCHES
Note: Paddle kits include screws and washers.

65
 Flow Switch Replacement Parts
Flow Switches – Air

Series aF2
Air Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 307000 FS7-31 SPDT switch 0.3 (.14)

2 301200 AF1-21 Gasket 0.1 (.05)

Series aF2
3 301400 AF2-122 Paddle kit 0.1 (.05)
(includes item 2)
Note: Paddle kits include screws and washers.
FLOW SWITCHES

66
Flow Switch Replacement Parts
Flow Switches – Air

Series aF3
Air Flow Switches
Components
Item Part Model Weight
Number Number Number Description lbs. (kg)

1 307000 FS7-31 SPDT switch 0.3 (.14)

2 301200 AF1-21 Gasket 0.1 (.05)

Series aF3
3 301450 AF3-122 Paddle kit 0.1 (.05)
(includes item 2)
Note: Paddle kits include screws and washers.

FLOW SWITCHES
1

67
 Warranty & Return Policy
Warranty Policy Return Goods Policy

McDonnell & Miller warrants for a period of two (2) years Unused material may be returned for credit only with the
from the date of manufacture or one (1) year from date of written or oral consent of McDonnell & Miller. This
installation, whichever comes first, that all McDonnell & consent is in the form of an RGA number issued by
Miller and all Hoffman Specialty products furnished by it McDonnell & Miller, and is subject to the following conditions.
are free from defects in materials and workmanship.
1. Materials must be unused, of current design, and in
McDonnell & Miller’s liability for any breach of this original cartons.
Warranty shall be limited solely to replacement or repair
2. Credit will be issued based upon either a referenced
at the sole option of McDonnell & Miller, of any part or
invoice or product date code if an invoice is not
parts found to be defective during the Warranty Period
referenced. Requestor is to supply copy of the
providing the Product is properly installed and is being
referenced invoice if requested.
used for its intended purpose. Buyer must notify
McDonnell & Miller of any breach of this warranty, within 3. A 25% restocking charge will apply.
the aforementioned Warranty Period by notifying the 4. Unauthorized material returned to McDonnell & Miller
McDonnell & Miller representative with responsibility for will be either refused or sent back to the sender freight
servicing the Buyer’s account. Further, product alleged to collect by a carrier chosen by McDonnell & Miller.
be defective must be shipped by buyer to McDonnell &
Miller’s representative, transportation charges prepaid. 5. If material is received but subsequently found not to
have met the above conditions, it will be sent back to
It is expressly agreed that this shall be the sole and the sender freight collect by a carrier chosen by
exclusive remedy of the buyer, under no circumstances McDonnell & Miller.
shall McDonnell & Miller be liable for any costs. loss,
expense, damages, special damages, incidental damages 6. Products which are obsolete or made to special order
or consequential damages arising directly or indirectly are not returnable.
form the design, manufacture, sale, or use or repair of
the product whether based upon warranty, contract,
negligence or strict liability. In no event will liability
exceed the purchase price of the product.
The warranty and limits of liability contained herein are in
lieu of all other warranties and liabilities expressed or
implied. All implied warranties or merchantability and
fitness for a particular purpose are hereby disclaimed by
McDonnell & Miller and excluded from the warranty.
McDonnell & Miller neither assumes nor authorizes any
person to assume for it, any other Warranty obligation in
connection with the sale of the Product. This Warranty
shall not apply to any product or parts of products which
(a) have been repaired or altered outside of authorized
McDonnell & Miller facilities; (b) have been subject to
misuse, negligence or accident; or (c) have been used in
a manner contrary to McDonnell & Miller instructions.
In the case of Products not manufactured by McDonnell &
Miller, there is no warranty from McDonnell & Miller, but
McDonnell & Miller will extend to the buyer any Warranty
from McDonnell & Miller’s supplier of such products
Warranty Procedure
WARRANTY & RETURN

Return product to place of purchase or contact our local

Manufacturer’s Representative.

68
Date Codes

McDonnell & Miller controls manufactured after 1972 See chart for more specific information on maintenance
feature a stamped date code, so you can easily check the and replacement intervals. Below are guides to help you
life expectancy and recommended replacement intervals. quickly locate and translate the date code on McDonnell
If a control has no date stamp replace it! & Miller controls.

Product Date Code Translation

WHERE TO FIND Month Year Example
97 = 1979
A = January 08 = 1980
18 = 1981
B = February 28 = 1982
38 = 1983
DATE CODES C = March 48 = 1984
58 = 1985
D = April 68 = 1986
78 = 1987 K09
E = May 88 = 1988 Translatesto
98 = 1989 October 1990
F = June 09 = 1990
19 = 1991
G=July 29 = 1992
39 = 1993
H=August 49 = 1994
59 = 1995
J = September
96 = 1996 Between
K=October 97 = 1997 1996and2008
98 = 1998 monthdesigner
L =November 99 = 1999 proceededyear
00 = 2000
M=December 01 = 2001 andyeardesignator
02 = 2002 wasnotreversed.
03 = 2003
04 = 2004 96K
05 = 2005 Translatesto
06 = 2006 October 1996
07 = 2007
08 = 2008
09 = 2009 Beginning2009
01 = 2010 monthdesignator
11 = 2011 proceedsyearand
21 = 2012 yeardesignatoris
31 = 2013 againreversed.
DATE CODES

41 = 2014
51 = 2015
61 = 2016
71 = 2017 K21
81 = 2018 Translatesto
91 = 2019 October 2012

69
 Recommended Maintenance

IMPORTANT
• Product repairs made with non-McDonnell & Miller manufacture.
parts will invalidate our warranty as well as any
• Use of water treatment can diminish product
agency recognitions. Without this recognition the
life. In such cases, components should be
product would no longer be eligible for use in listed
replaced on a more frequent basis.
end-use equipment.
• Visually inspect the inside of the float
• Previously used controls should never be
chamber during the annual inspection.
installed on a new system. Always install new
Partial disassembly may be required.
controls on a new boiler or system.
• A more frequent replacement interval may be
necessary based on the condition of the unit
at time of inspection. McDonnell & Miller’s
warranty is one (1) year from date of
installation or two (2) years from the
date of

Inspect all controls annually, and replace, repair or McDonnell & Miller products must also be maintained
clean, as needed. All chambered units are to be blown in accordance with the following ASME Code.
down per manufacturers instructions and local code
requirements. These requirements are to be determined
by the local service company, and are based on water
quality and system operation variables. Refer to the
installation instructions provided with the product for
specific assembly and test procedures.

ASME Boiler and Pressure Vessel Code – Section VI Paragraph 7.07 G

Low-Water Fuel Cut-Off and Water Feeder mechanisms, including necessary gaskets and installation
Maintenance. Low-water fuel cut-offs and water feeders instructions are available from the manufacturer. After
should be dismantled annually, by qualified personnel, to reassembly, test as per 7.05H.
the extent necessary to insure freedom from obstructions
and proper functioning of the working parts., Inspect
connecting lines to boiler for accumulation of mud, scale,
etc., and clean as required. Examine all visible wiring for
brittle or worn insulation and make sure electrical
contacts are clean and that they function properly. Give
special attention to solder joints on bellows and float
when this type of control is used. Check float for evidence
of collapse and check mercury bulb (where applicable) for
mercury separation or discoloration. Do not attempt to
repair mechanisms in the field. Complete replacement
RECOMMENDED MAINTENANCE

70
Replacement Guidelines
Recommended
Replacement Intervals
Recommended
Replacement
Recommended Interval
Product Series Maintenance (Maximum)
1575, 150S, 157S, Blow down and test daily 15 years
158S, 159S inspect annually.
69, 169, 269, Inspect and test annually. 10 years
369, 469
67, 767 Blow down weekly. Inspect and 10 years
test annually.
61, 63, Blow down weekly. Inspect and 10 years
Low Water Cut-Offs 64, 764 test annually.
42S Blow down daily. Inspect and 10 years
test annually.
93, 94, Blow down and test daily. 15 years
193, 194 Inspect and test annually.
750, 751P/752P, PSE-800 Inspect and test annually. 15 years
RB-122E
RB-24E Inspect and test annually. 10 years
WFE/Uni-Match ®
Inspect and test annually. 10 years
21, 221, 25-A, 51-S, 53, Inspect and test annually. 15 years
Water Feeders
851-S, 3155
Inspect Annually
101-A, 47, 51, 247 Blow down weekly. Inspect and 10 years
847, 551-S, 851 replace cartridge valve annually.
PFC Inspect and test annually. 15 years
Liquid Level Controls Blow down weekly
27-W Inspect and test annually. 5 years
Replacement 14-B Inspect and test annually. 10 years
Blow Down Valves
Replacement 751P/752P, PSE-800 Self cleaning probes. 10 years
Probes RB-122E Inspect 5 years.
Replacement Head 25-A, 42S, 51, 51-S, Inspect and test annually. 5 years
Mechanisms for 53, 61, 63, 64, 67, 93
Commercial/Industrial 94, 150S, 157S,
Applications 193, 194
Inspect and test annually. 10 years
Flow Switches FS1, FS4-3, FS5,
FS43T, FS6, FS7-4,
REPLACEMENT GUIDELINES

FS8W, AF, FS-250

71
 Notes

notes

Flow Switch Replacement Parts

 Notes

notes

Flow Switch Replacement Parts

 Notes

notes

Flow Switch Replacement Parts

Xylem
1) The tissue in plants that brings water upward from the roots;
2) a leading global water technology company.

We’re a global team unified in a common purpose: creating advanced technology solutions to
the world’s water challenges. Developing new technologies that will improve the way water is
used, conserved, and re-used in the future is central to our work. Our products and services move,
treat, analyze, monitor and return water to the environment, in public utility, industrial, residential
and commercial building services, and agricultural settings. With its October 2016 acquisition of
Sensus, Xylem added smart metering, network technologies and advanced data analytics for water,
gas and electric utilities to its portfolio of solutions. In more than 150 countries, we have strong,
long-standing relationships with customers who know us for our powerful combination of leading
product brands and applications expertise with a strong focus on developing comprehensive,
sustainable solutions.

For more information on how Xylem can help you, go to www.xyleminc.com

The Little Red Schoolhouse® - Training the Industry

Bell & Gossett has long been known for its dedication to
training. The “Little Red Schoolhouse®“ has graduated over
60,000 students since it was founded in 1954.

Graduates from the “Little Red Schoolhouse” may be found

throughout North America, Europe, Africa, Asia and Australia.

For applications to attend these seminars, please contact

a Bell & Gossett Representative in your area. They will
have the schedule dates for all seminars and will make all
the arrangements for you. As a service and a continuing
Seminars currently offered are: educational source to the HVAC industry, these seminars
• Modern Hydronic System Design – Basic* are offered free of charge. IACET certified CEU credits are
• Modern Hydronic System Design – awarded for each seminar.
Advanced*
* The USGBC has approved the technical and instructional
• Design & Application of Water Based
quality of the Modern Hydronic Heating Systems - Basic
HVAC Systems
Seminar (15 GBCI CE Hours) and the Large Chilled Water
• Large Chilled Water System Design*
Design Seminar (11 GBCI CE Hours). These courses are
• Pump Service & Maintenance School
approved for GBCI Continuing Education Hours towards
• Steam Systems Design & Applications LEED Credential Maintenance Programs.
• Steam System Operation & Maintenance
• Plumbing Systems Design

Xylem Inc.
8200 N. Austin Avenue
Morton Grove, Illinois 60053
Phone: (847) 966-3700
Fax: (847) 965-8379
www.mcdonnellmiller.com
McDonnell & Miller is a trademark of Xylem Inc. or one of its subsidiaries.
© 2017 Xylem Inc. MM-701E November 2017