Honeywell LP916A Mounting instructions

LP916A-C Pneumatic
Remote Bulb Thermostats
Copyright © 1987 Honeywell Inc. • All Rights Reserved
75-5559
SERVICE DATA
GENERAL
DESCRIPTION
The LP916 Thermostats are bleed-type controllers with a
fixed throttling range. They have a liquid-filled, remote
thermal element.
APPLICATION
Typical applications for the LP916A are duct-mounted (Fig. 1)
and mixed air control (Fig. 2). The LP916B is typically used
for fan coil unit control (Fig. 3). Typical applications for the
reverse acting LP916C are cooling coil control similar to
Figure 1 or fan coil control (Fig. 4).
Fig. 1.Typical LP916A duct-mounted heating application.
Fig. 2.Typical LP916A mixed air application.
Fig. 3.Typical LP916B fan coil application, heating/
cooling with seasonal changeover.
S5785-2
S5783-1
S3803-1

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LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
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Fig. 4.Typical LP916C fan coil application, cooling only.
SPECIFICATIONS
Models:
LP916A: Direct Acting.
LP916B: Reverse acting at 9 or 13 psi (62 or 90 kPa)
supply pressure (Summer), direct acting at 18 psi
(124 kPa) supply pressure (Winter).
LP916C: Reverse Acting.
Maximum Safe Air Pressure:
25 psi (172 kPa).
Maximum Safe Temperature:
Duct-mounted models 190F (88C); all others 135F (57C).
Nominal Main-Line Pressure:
LP916A & C: 18 psi (124 kPa).
LP916B: 18 psi (124 kPa) heating, 9 or 13 psi (62 or
90 kPa) Cooling.
For other LP916 specifications refer to Table 1.
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LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
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Table 1. LP916 Specifications.
Model Setpoint
Range F/C Throttling Range F/C Restrication Size In. Bulb Size Inches
Inactive or obsolete.
Mounting
Bracket
0.007
1LP916A1001 65-85F 3.5F 3/8 x 9 Separate
LP916A1019 65-85F or 19-30C 3.5F or 2C 0.007 1/2 x 5 Integral
55-95F 7.0F 0.007 3/8 x 6-11/16LP916A1035 1 Integral
1LP916A1027 65-85F 3.5F 0.007 3/8 x 9 Integral
LP916A1050 17-27C 1.95C 0.007 1/2 x 5 Integral
17-27C 1.95C 0.007 3/8 x 9LP916A1068 Integral
13-35C 3.89C 0.007 3/8 x 6-11/16LP916A1076 Integral
17-27C 1.95C 0.007 3/8 x 9LP916A1084 Integral
35-115F 0.007 3/8 x 3-1/214.0F
LP916A1100 Integral
55-95F 0.007 3/8 x 77.0FLP916A1118 Integral
3.5F or 2C65-85F or 19-30CLP916A1134 0.005 3/8 x 9 Integral
55-95F 7.0F 0.005 3/8 x 6-11/16LP916A1142 Integral
17-27C 1.95C 0.005 3/8 x 9LP916A1159 Integral
LP916A1175 0.007 3/8 x 77.0F or 4C40-80F or 4-27C Integral
3.5F or 2C65-85F or 19-30CLP916B1017 0.007 1/2 x 5 Integral
65-85F 3.5F 0.007 3/8 x 9LP916B1025 Integral
17-27C 1.95C 0.007 3/8 x 9LP916B1041 Integral
3.5F or 2C65-85F or 19-30CLP916B1058 0.007 1/2 x 5 Integral
65-85F 3.5F 0.007 3/8 x 9LP916B1066 Integral
3.5F or 2C65-85F or 19-30CLP916B1082 0.005 1/2 x 5 Integral
17-27C 1.95C 0.005 3/8 x 9LP916B1090 Integral
3.5F or 2C65-85F or 19-30CLP916B1108 0.005 3/8 x 9 Integral
65-85F 3.5F 0.007 3/8 x 9LP916C1007 Integral
17-27C 1.95C 0.007 3/8 x 9LP916C1015 Integral
LP916C1023 60-80F or 16-27C 3.5F or 2C 0.007 3/8 x 9 Integral
3.5F or 2C65-85F or 19-30C 0.007 1/2 x 5LP916C1049 Integral
35-115F 0.007 3/8 x 3-1/214.0FLP916C1072 Integral
55-95F 0.007 3/8 x 77.0FLP916C1080 Integral
3.5F or 2C65-85F or 19-30CLP916C1098 0.005 3/8 x 9 Integral
40-80F or 4-27C 0.007 3/8 x 77.0F or 4CLP916C1114 Integral
17-27C 3.80C 0.007 3/8 x 6-11/16LP916A1092 Separate
65-85F or 19-30C 3.5F or 2CLP916A1126 0.005 3/8 x 9 Separate
0.007 3/8 x 93.5F65-85FLP916B1009 Separate
3.5F or 2C65-85F or 19-30CLP916B1074 0.005 3/8 x 9 Separate
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1

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LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
75-5559
OPERATION
LP916A (Direct Acting)
When temperature at the sensing element falls below setpoint
of the LP916A, branchline pressure to the normally open
(n.o.) valve is lowered, and the valve is modulated open to
maintain setpoint temperature.
LP916B (Reverse/Direct Acting)
With main-line pressure at 13 psi (90 kPa) for all except
LP916B1058 which requires 9 psi (62 kPa), the LP916B
operates reverse acting. As the sensed temperature
increases, the branchline pressure decreases and chilled
water flow increases with a n.o. valve.
With a high main-line pressure of 18 psi (124 kPa) or above,
the LP916B operates direct acting. As the sensed
temperature increases, the branchline pressure increases
and hot water flow decreases with a n.o. valve.
LP916C (Reverse Acting)
When the LP916C is used with a normally open valve for
cooling, branchline pressure drops with a rise in sensed air
temperature and the n.o. valve is modulated open to maintain
setpoint temperature.
MAINTENANCE
EQUIPMENT REQUIRED
— Commercial Cleaning Solvent or Degreaser.
— Gage Adaptor CCT729A.
— Gage 305965, 0 to 30 psi.
— 5/64-inch Hex wrench.
WARNING
Careless handling of solvents can result in permanent
damage to the respiratory system or skin. Avoid
prolonged inhalation of vapors or contact with skin.
CLEANING
Remove cover. Use cleaning solvent to clean all surfaces.
Clean the element and capillary tubing, making certain
neither is damaged or kinked. Do not bend the capillary
tubing in a short radius.
OPERATIONAL CHECK
Use gage adaptor. Insert the gage into the gage tap (Fig. 5)
on the front of the device. Set main-line pressure to 18 psi
(124 kPa), or 13 psi (90 kPa) for LP916B Summer
application. Slowly turn the setpoint knob above and below
bulb ambient temperature. The branchline pressure should
vary from 3 to 13 psi (21 to 90 kPa) pressure, or 13 to 3 psi
(90 to 21 kPa) for reverse acting application within the rated
throttling range. If operation is not satisfactory, recalibrate and
recheck (see CALIBRATION). Turning the knob to above 13
psi (90 kPa) should build branch line to within 2 psi (14 kPa)
of main.
Fig. 5. LP916 Gage tap location.
GAGE TAP
C2861
COOLER
NORMAL
WARMER

LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
575-5559
CALIBRATION CHECK
Set setpoint knob to temperature measured at bulb location.
Branchline pressure should be 8 ±1 psi (55 ±7 kPa).
CALIBRATION
LP916A & C
AApply 18 psi (124 kPa) main-line pressure.
BMeasure temperature at sensing bulb location.
CRemove setpoint knob using 5/64-in hex wrench to
loosen setscrew.
DRotate setpoint shaft to achieve 8 psi (55 kPa)
branchline pressure. Allow enough time for pressure
build-up.
EReplace the knob and position the pointer to
correspond to the temperature sensed by the remote
bulb.
LP916B
AFor direct action, follow Steps 1 through 5 for LP916A
and C.
BFor reverse action (except LP916B1058), apply 13 psi
(90 kPa) main-line pressure. For the LP916B1058,
apply 9 psi (62 kPa) main-line pressure.
CAdjust switchover lever stop (Fig. 6) to achieve 8 psi
(55 kPa) branchline pressure when the setpoint knob is
set to measured bulb temperature. For the
LP916B1058 model, branchline pressure should be
6 psi (41 kPa).
Fig. 6. LP916B Automatic switchover mechanism.
SWITCHER
LEVER STOP
SWITCHER
SPRING
ADJUSTING NUT STUD C8363

6
LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
75-5559
TROUBLESHOOTING
Before troubleshooting the LP916, check branchline piping
and actuators for leaks.
Refer to Figure 7 to troubleshoot the LP916 Thermostat.
Fig. 7. LP916Troubleshooting flowchart.
CHECK
CALIBRATION
CHECK MAIN
AIR
PRESSURE
DISCONNECT
BRANCH LINE AT
CONTROLLER
AND PLUG
OUTLET
CONTROLLER OK.
CHECK PIPING AND
ACTUATOR FOR
LEAKS
REPLACE
CONTROLLER
PRESSURE
BLEEDS OFF
WHEN SETPOINT
IS MOVED IN
OPPOSITE
DIRECTION?
PRESSURE
BUILDS UP
SMOOTHLY
WHEN SETPOINT
IS CHANGED?
CORRECT
PRESSURE
FOR SEASON
OR
APPLICATION?
OPERATES
PROPERLY
?
BEGIN
MAKE
OPERATIONAL
CHECK
PRESSURE
BUILDS UP
PROPERLY?
TROUBLESHOOT
AIR SUPPLY
YES
YES NO
YES
NO
NO
NO
YES
NO YES
RECALIBRATE
CALIBRATION
OK?
NO
YES
REPLACE FILTERS AND
RESTRICTION PLATE
C2860

LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
775-5559
REPAIR
The only repair recommended for the LP916 is the
replacement of the plate and tube assembly, gaskets,
restriction plate, and filters with connector assembly and
gasket. Since February 1984, models have a different
connector assembly with a single gasket, these are included
in Repair Kit 14003113-002, as shown in Figure 8. All
available parts are listed in the PARTS AND ACCESSORIES
section.
EQUIPMENT REQUIRED
Gulmite Head Screw Wrench 316744-00021.
14003113-002 REPAIR KIT INSTALLATION
ATurn off system air and remove LP916 from system.
BRemove and save the three No. 8-32 x 7/16-in. pan
head screws from the connector assembly (Fig. 8) or
plate and tube assembly (Fig. 9 or 10).
CLift off the connector assembly and gasket or plate and
tube assembly, restriction gasket, restriction plate, body
gasket, and two filters and discard.
DPlace new gasket on body and align screw holes.
EPosition the new connector assembly on gasket and
align screw holes. A 0.007 in. restriction may be used
for models with a 0.005 in. restriction with no effect on
operation except a slightly higher air consumption. If air
consumption is a problem, connector assembly with a
0.005 in. restriction may be ordered and substituted.
FInsert and tighten the three screws.
GMake operational check (See OPERATIONAL CHECK).
NOTE: For 14003113-001 Repair Kit follow directions on
package.
Fig. 8. Repair kit 14003113-002 (0.007 in. restriction
included in kit).
INDICATES 0.005 IN. RESTRICTION
INDICATES 0.007 IN. RESTRICTION
CONNECTOR
ASSEMBLY
GASKET
C8362

8
LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
75-5559
PARTS AND ACCESSORIES
PARTS LIST
See Figure 9 for LP916A &C exploded view and Figure 10 for
LP916B exploded view. See Tables 2 and 3 for LP916A &C
parts list and Tables 3 and 4 for LP916B parts list.
Table 2. LP916A and C Parts list (Fig. 9).
Key Part No. Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
316294
—
—
—
—
—
—
—
—
—
—
—
—
14003113-001
—
—
—
—
—
—
14004378-001
14004378-002
14004376-001
14003113-002
—
—
—
—
316372A
316372B
316372C
—
—
—
—
Cover
6-32 x 3/16 in. rd-hd slotted screw
6-32 x 1/4 in. pan-hd slotted screw with washer (2)
Spring
Plate
6-32 x 0.31 (5/16) in. rd-hd slotted screw with washer (2)
Base
Baseplate
Scaleplate
8-32 x 5/16 in. slotted pan-hd screw (7)
Palnut
Setpoint Shaft
Knob (includes 8-32 x 5/16 in. hex socket setscrew). Use 5/64 in. key to tighten.
Repair Kit—Consists of Filters, Body Gasket, 0.007 Restriction, and Restriction Gasket
Filters (2)
BodyGasket
0.007 Restriction Plate
Restriction Gasket
Plate and Tube Assembly
8-32 x 7/16 in. pan-hd slotted screw (3)
Connector Assembly (0.007)
Connector Assembly (0.005)
Gasket
Repair Kit—Consists of 14004378-001 Connector Assm. (0.007) & 14004376-001 Gasket
Nozzle
Flapper
Spring
4-40 x 3/16 rd-hd slotted screw
Element and Lever Assembly (see Table 3)
Element and Lever Assembly (see Table 3)
Element and Lever Assembly (see Table 3)
Lever (LP916A)
Lever (LP916C)
Spring
8-32 x 5/16 in. pan-hd slotted screw with star lockwasher

LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
975-5559
Fig. 9. LP916A and C Exploded view (SeeTables 2 and 3).
S22649

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LP916A-C PNEUMATIC REMOTE BULB THERMOSTATS
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Table 3. LP916A-C Element and lever assemblies.
Table 4. LP916B Parts list (Fig. 10).
Assembly
Part No. Part No. Bulb Size in. (mm)
316372A A1001, A1027, A1068, B1009,
B1025, B1041, B1066, C1007,
C1023
3/8 x 9-1/2
(9.5 x 241)
316372B A1019, B1017, B1058, C1049 1/2 x 5-3/4
(13 x 146)
316372Ç A1035, A1076, A1118, A1126,
A1134, A1142, A1159, A1175,
B1074, B1082, B1090, B1108,
C1080, C1098, C1114
3/8 x 6-3/4
(10 x 172)
Key Part No. Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15|
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
316294
—
—
316372A
316372B
316372C
—
—
—
—
—
—
—
—
—
—
—
—
—
—
316732
14003113-001
—
—
—
—
—
—
14004378-001
14004378-002
14004376-001
14003113-002
—
—
—
—
—
—
—
Cover
Nut
Lever
Element and Lever Assembly (see Table 3)
Element and Lever Assembly (see Table 3)
Element and Lever Assembly (see Table 3)
Stud
Spring
Lever
4-48 x 3/16 in. hex-hd screw
4-48 nut
8-32 x 0.31 (5/16) in. rd-hd slotted screw with washer (2)
Base
Spring
Disc Assembly
Diaphragm
Baseplate
8-32 x 5/16 in. slotted pan-hd screw (7)
Palnut
Setpoint Shaft
Knob (includes 8-32 x 5/16 in. hex socket setscrew). Use 5/64 in. key to tighten.
Repair Kit—Consists of Filters, Body Gasket, 0.007 Restriction, and Restriction Gasket
Filters (2)
BodyGasket
0.007 Restriction Plate
Restriction Gasket
Plate and Tube Assembly.
8-32 x 7/16 in. pan-hd slotted screw
Connector Assembly (0.007)
Connector Assembly (0.005)
Gasket
Repair Kit—Consists of 14004378-001 Connector Assm. (0.007) & 14004376-001 Gasket
Nozzle
Flapper
Spring
4-40 x 3/16 in. rd-hd slotted screw (3).
6-32 x 3/16 in. rd-hd slotted screw
Spring
8-32 x 5/16 in. pan-hd slotted screw with star lockwasher (2)