Johnson Controls GM 20 Series User manual

Installation Sheets Manual 121
Gas Combustion Combination Controls and Systems Section G
Technical Bulletin GM-20/25
GM-40/45
Issue Date 1298
© 1998 Johnson Controls, Inc. 1
Part No. 24-8711-48, Rev. A www.johnsoncontrols.com
Code No. LIT-121892
Introduction Page 3
x Application 3
x Electrical Ratings 3
x Specifications 4
Installation 5
x Mounting 5
x Standard Wiring (From Burner Sequence Control) 6
x 4-Pin Connector Plug Wiring (From Burner Sequence Control) 8
x GM-4_6_ Connection of Impulse Lines 9
x Checkout Procedure 10
Adjustments 11
x GM-_ _1_ (Dual On/Off Fast Open with Flow Adjustment) 11
x GM-_ _2_ (Dual On/Off Step-slow Opening with Flow Adjustment) 12
x GM-_ _3_ (Dual On/Off with Pressure Regulator) 12
x GM-_ _4_ (Dual On/Off with Step-slow Opening with Pressure Regulator) 13
x GM-4_5_ (Dual On/Off with Servo Precision Regulator) 13
x GM-4_6_ (Dual On/Off with Gas/Air Ratio Control) 15
Repairs and Replacement 19
GM-20/25 and GM-40/45 Series
Dual-block Multi-function Gas Control Valves
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2 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 3
Introduction
Figure 1: GM Series Dual-block Multi-function
Gas Control Valves
The GM Series dual-block multi-function gas control valves are intended
for use on atmospheric and forced-draft gas burners in heating
installations. This multi-functional control on a dual-block valve body
provides a compact answer to gas train applications. The GM valve
replaces multiple gas train components, such as on/off gas valves, gas
pressure regulators, and modulating gas valves. Optional sizing of body
flanges offers greater adaptation to diversified burner designs and
applications. Valves are approved to European and North American gas
valve standards.
Typical applications include boilers, burners and ovens, rooftop units,
makeup air heaters, hot water heaters, kilns, and paint booths.
Table 1: Electrical Ratings
Valve Model Operating Voltages Power Consumption
GM-2_ _ _ 230 VAC +10/-15%, 50/60 Hz
120 VAC +10/-15%, 50/60 Hz
24 VAC +10/-15%, 50/60 Hz 46 VA
GM-4_ _ _ 230 VAC +10/-15%, 50/60 Hz
120 VAC +10/-15%, 50/60 Hz
24 VAC +10/-15%, 50/60 Hz 46 VA
Application
Electrical
Ratings
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4 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
Table 2: Specifications
Media 1st (Manufactured Gas), 2nd (Natural Gas), and 3rd (Liquefied
Petroleum [LP] Gas) Family Gases
Maximum Inlet
Pressure
Europe:
GM-_01 _ and GM-_02_: 360 mbar
GM-251_ and GM-252_: 200 mbar
All Other Models 100 mbar
North America:
GM-_01 _ and GM-_02_: 5 psi
GM-251_ and GM-252_: 2 psi
All Other Models 0.5 psi
Maximum
Regulating
Setting
20 mbar (8 in. W.C.) (GM-_ _3_ and GM-_ _4_)
50 mbar (20 in. W.C.) (GM-4_5_ and GM-4_6_)
Reverse
Pressure Rating 150 mbar (60 in. W.C.) minimum; Class A (EN 161)
Regulator
Classification Spring Regulator (GM-_ _3_ and GM-_ _4_): Class B (EN 88)
Servo Regulator (GM-4_5_): Class A (EN 88)
Permissible
Ambient
Temperature
-15 to 60°C (5 to 140°F)
Body
Connections Detachable flanges with pipe thread 3/8 to 1-1/2 in. NPT or Rp
Valve Torsion
Group Group 2 (EN 88 and EN 161)
Pressure Taps Flanges: 9.0 mm (0.35 in.) spigot for flexible tubing
Body: Rp 1/8 thread standard (multi-position)
Rp 1/4 thread special (multi-position) GM-4 only
Materials Body and Flanges: Die-cast aluminum
Diaphragms and Seals: Perbunan rubber
Solenoid Enclosure: IEC 529 (NEMA 1 and IP 54)
Filter Segment Standard Dirt Strainer: 0.5 mm (0.02 in.) metal mesh
Optional Filter Set: 0.05 mm (0.002 in.) nylon mesh and fleece filter
Operating Time
Rating 100% Continuous
Valve Timings Closing Time: < 1 second
Opening Time: < 1 to 15 seconds
Dead Time: < 1 second
Electrical
Connections Standard Wiring: PG 13.5 compression fitting with cage-type
terminal blocks inside the electrical box
Optional Wiring: 1/2 in. NPT conduit adapter compression fitting or
4-pin connector plug (ISO 4400 [DIN 43650])
Coil Insulation
Class Class F
Agency Listings IAS (AGA/CGA) Certificate Numbers: C0197002
C0197004
European Certificate Number: CE 0063AN3731
Specification
Standards EN 88, EN 126, and EN 161
Standards Complying with the EMC Directive
Standards Complying with the Low Voltage Directive
ANSI Standards, Z21.18, Z21.21, and Z21.78
Canadian Standards CAN1-6.3 and CAN1-6.5
The performance specifications are nominal and conform to acceptable industry standards. For
application at conditions beyond these specifications, consult the local Johnson Controls office.
Johnson Controls, Inc. shall not be liable for damage resulting from misapplication or misuse of its
products.
Refer to the GM-20/25 and GM-40/45 Series Product Bulletin (LIT-4350340) for necessary information on
operating and performance specifications of this product.
Specifications
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 5
Installation
IMPORTANT: This technical bulletin is intended as a guide for
authorized service personnel installing or servicing
Johnson Controls products. Carefully follow all
instructions in this sheet and all instructions on the
appliance. Limit repairs, adjustments, and servicing to
the operations listed in this sheet or on the appliance.
!
WARNING: The system must meet all applicable codes. Improper
installation may cause fire, explosions, property
damage, and injuries or death.
Carefully follow all instructions in this sheet and all instructions on the
appliance. Limit repairs, adjustments, and servicing to the operations listed
in this sheet or on the appliance.
!
WARNING: Fire or explosion hazard. Shut off the gas supply at
the main manual shutoff valve before installing or
servicing the GM Series valve.
1. Ensure that the maximum ambient temperature is not exceeded
(see Table 2).
2. Check the power supply voltage for compatibility with the required
valve voltage. All wiring must conform to national and local electrical
codes and regulations.
3. When installing the valve on the manifold, the gas must flow through
the valve body in the direction indicated by the arrow on the body. If
the valve is installed with the gas flow opposite the arrow, leakage can
occur.
4. Shut off the gas at the main manual shutoff valve.
5. Mount the valve. It is recommended that the flanges be mounted to
the pipe separately with the valve then mounted between the
two flanges. The filter plate assembly should be installed (using the
longer bolts) between the inlet flange and the valve.
Mounting
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6 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
The GM Series valve may be mounted on a horizontal manifold with
the solenoid actuator pointed up (vertical) or in any position not
exceeding 90ofrom the vertical. The valve may also be mounted on a
vertical manifold in any position around its axis (see Figure 2). Do not
install the solenoid actuator upside down. Install vertically wherever
possible.
90° Maximum
from Vertical
90° Maximum
from Vertical
Limited Horizontal and Vertical
Figure 2: GM Series Valve Mounting Position
Use an approved pipe joint sealing compound on male threads before
assembly.
6. Remove excess compound after mounting the flanges to the pipe.
Threads of pipe and nipples must be smooth and free of tears and
burrs. Steam clean all piping to remove foreign substances such as
cutting oil or thread chips.
!
WARNING: Shock hazard. Avoid electrical shock and equipment
damage by disconnecting electrical power to the valve
before proceeding.
!
CAUTION: Equipment damage hazard. To prevent possible
grounding of the 24 VAC transformer secondary, do
not connect the ground wire on 24 VAC models.
Follow the procedure below to wire the valve when using the standard
PG 13.5 cable compression electrical connection.
1. Observe that the operating voltage is identical to the information on
the product identification label.
2. Route the electrical cable for the valve solenoid from the burner
sequence control to the valve.
3. Remove the cover of one of the electrical box and make wiring
connections in accordance with Figure 3.
4. Reattach the electrical box cover.
Standard Wiring
(From Burner
Sequence
Control)
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 7
Note: Figure 3 shows wiring connections for individual valve opening.
For simultaneous valve opening, wire a jumper between
Terminals V1 and V2 of either the electrical box on the first or
second valve.
5. Use a wrench to tighten the PG 13.5 cable compression plug to secure
wires and prevent moisture from entering the terminal box.
Note: If an optional 1/2 in. NPT thread electrical connector or 4-pin
DIN 43650 (ISO 4400) electrical connector (each ordered
separately) is used for wiring, refer to the documentation supplied
with the electrical connector for specific wiring instructions.
V1 V2
V1
V2
N
NV2V1 NV1V2
V1
V2
V1
V2
Addtional Connection
(
Ma
y
be used to connect pilot
or b
y
pass valves. Break awa
y
plastic to open.
)
GND GND
GND
*
Electrical Box
Connection
*
PG 13.5 Cable
Compression Plu
g
(
Factor
y
Installed
)
Wirin
g
Connections
N = Common
V1 = Line Valve 1
V2 = Line Valve 2
GND = Earth Ground*
(
* Do not connect earth
g
round
for 24 VAC models.
)
Figure 3: Standard Wiring Electrical Connections
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8 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
!
WARNING: Shock hazard. Avoid electrical shock and equipment
damage by disconnecting electrical power to the valve
before proceeding.
!
CAUTION: Equipment damage hazard. To prevent possible
grounding of the 24 VAC transformer secondary, do
not connect the ground wire on 24 VAC models.
Use the following procedure to wire the valve when using a factory-
installed 4-pin DIN 43650 (ISO 4400) electrical plug connection.
1. Observe that the operating voltage is identical to the information on
the product identification label.
2. Route the electrical cable for the valve solenoid from the burner
sequence control to the valve.
3. Make wiring connections in accordance with Figure 4.
Note: Figure 4 shows wiring connections for individual valve opening.
For simultaneous valve opening, wire a jumper between terminals
V1 and V2 of either the electrical box on the first or second valve.
PE
(
Ground
)
2
3
1N
(
Common
)
1
32
Line
(
Valve 1
)
Line
(
Valve 2
)
Terminal Desi
g
nations
V1 V2
Figure 4: 4-Pin Wiring Electrical Connections
4-Pin Connector
Plug Wiring
(From Burner
Sequence
Control)
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 9
The internal diameter of the impulse tubes for the combustion air (PA) and
the combustion chamber pressure (PF) should be 4.0 mm (5/32 in.), see
Figure 5. Make the connections as short as possible and route to prevent
the entry of condensate into the controller. The installation of a
condensation trap in the connection line from the combustion chamber is
highly recommended. Do not close the connection for PFif not used.
IMPORTANT: Avoid sharp bends or kinks in the tubing to avoid
damage to the tubing and allow for an accurate pressure
reading.
P
F
P
A
Figure 5: Impulse Line Connections
GM-4_6_
Connection of
Impulse Lines
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10 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
!
WARNING: Fire or explosion hazard. Verify that the valve
functions properly and there are no gas leaks. Follow
this checkout procedure before leaving the installation.
Failure to verify proper valve installation, equipment
operation, and gas tight connections may result in fire,
explosion, property damage, and injuries or death.
1. Shut off the gas at the main manual shutoff valve and open the
pressure connection between the manual shutoff valve and the GM
valve.
2. Connect air tubing with a maximum pressure of 1-1/2 times the
valve’s maximum operating pressure (as indicated on the valve) to the
opened pressure connection.
3. Paint the pipe connections and flanges of the valve with a rich soap
and water solution to check for leakage.
If bubbles occur, this is an indication of a leak. To stop a leak, tighten
joints and pipe connections. Replace the part if the leak cannot be
stopped.
If bubbles do not occur, remove the air tubing and close the upstream
pressure connection.
4. Open the main manual shutoff valve.
5. Refer to the Adjustments section to make any necessary valve setting
adjustments.
!
WARNING: Fire or explosion hazard. Valve settings must be in
accordance with the appliance or equipment
manufacturer’s specifications.
6. Before leaving the installation, observe at least three complete
operating cycles to ensure that all components are functioning
correctly.
Checkout
Procedure
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 11
Adjustments
IMPORTANT: All adjustments must be made in conjunction with the
gas appliance and in accordance with the appliance
manufacturer’s instructions. Only authorized
personnel should make adjustments. See each valve
model version for specific adjustments.
!
WARNING: Explosion hazard. The minimum flow rate of the
valve must not be adjusted below the minimum safe
working rate of the appliance.
It is recommended that the flange pressure tap connections be used to
monitor the inlet and outlet valve pressure while performing each of the
specific adjustment procedures. These pressure connections are located on
the inlet and outlet flanges of the valve in the form of a brass spigot,
sealed with a captive brass needle screw. To monitor the inlet or outlet
pressure using these taps, turn the appropriate needle screw in a
counterclockwise direction one or two turns and fit a 9 mm diameter
flexible tube over the spigot. After all valve adjustments have been made,
remove the flexible tube and turn the needle screw in a clockwise direction
until tight, sealing the spigot.
This valve provides manual flow adjustment throughout the full range of
zero to maximum flow. For flow rate adjustment, loosen the unsealed
mounting screw on the plastic adjustment knob at the top of the solenoid
coil. Hand turn the adjustment knob clockwise to decrease
or counterclockwise to increase the flow rate through the valve (see
Figure 6). Tighten the mounting screw to secure the adjustment knob at
the desired flow rate.
Figure 6: Manual Flow Adjustment Knob
GM-_ _1_
(Dual On/Off
Fast Open
with Flow
Adjustment)
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12 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
This valve provides adjustable step/slow opening for smooth ignition in a
burner application. The valve is factory set to maximum start gas position
and maximum flow position. Adjust the hydraulic damper at the top of the
solenoid coil to set the desired flow rate through the valve as well as the
desired start gas flow rate.
To adjust the maximum flow rate, loosen the unsealed mounting screw on
the aluminum hydraulic damper housing. Hand turn the housing clockwise
until the desired setting is obtained. Tighten the mounting screw to secure
the adjustment knob at the desired flow rate.
To adjust the start gas position, remove the plastic cap from the hydraulic
damper housing and turn the brass screw clockwise until the desired
setting is obtained (see Figure 7). Replace the plastic cap.
A
V
M
A
X
.
Figure 7: Hydraulic Damper Housing
This valve provides spring regulation to maintain the gas pressure at the
valve outlet. For outlet pressure adjustment, loosen the unsealed mounting
screw on the plastic regulator knob at the top of the solenoid coil. Hand
turn the regulator knob clockwise to increase or counterclockwise to
decrease the outlet pressure of the valve (see Figure 8). Tighten the
mounting screw to secure the adjustment knob at the desired outlet
pressure.
S
O
L
L
W
E
R
T
S
T
.
/ R
E
G
.
S
E
T
P
O
I
N
T
Figure 8: Spring Pressure Regulator Adjustment Knob
GM-_ _2_
(Dual On/Off
Step-slow
Opening
with Flow
Adjustment)
GM-_ _3_
(Dual On/Off
with Pressure
Regulator)
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 13
This valve provides controls for step/slow opening (for smooth ignition)
and pressure regulation (for maintaining outlet gas pressure).
Refer to the GM-_ _3_ version for setting the gas pressure at the valve
outlet. For setting of the start gas position and maximum flow rate, see the
GM-_ _2_ version.
This valve provides servo regulation for precision control of the valve
outlet pressure. To set the valve for the desired outlet pressure, the start
gas pressure must be adjusted first.
To set the start gas position, energize the solenoid coil to open the valve
seats. Remove the pressure tap plug (see Figure 9) located below the gas
outlet pipe connection and measure the start gas pressure. The adjustment
scale (PST) indicates the factory-set start gas pressure (see Figure 10);
therefore, a subsequent fine adjustment may be necessary. Use the
hexagonal tool provided (or an acceptable Allen wrench) to adjust the PST
scale and obtain the desired start gas pressure.
Pressure
Tap Plu
g
Figure 9: Valve Outlet Pipe Connection
P
ST
P
G
5-50
2
6
10
Figure 10: PST and PGAdjustment Scales (Metric Shown)
GM-_ _4_
(Dual On/Off
Step-slow
Opening with
Pressure
Regulator)
GM-4_5_
(Dual On/Off
with Servo
Precision
Regulator)
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14 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
The start gas pressure (PST) remains at the set level until the pressure tap
plug is replaced and tightened. The pressure then rises to the setpoint (PG).
IMPORTANT: PGmust be greater then PST in order for the valve to
operate properly.
Once the desired start gas pressure has been obtained, the outlet pressure
(PG) can be adjusted. To set the outlet pressure position, energize the
solenoid coil to open the valve seats. Remove an outlet pressure tap plug
from the valve body and measure the servo pressure regulator performance
and timing characteristics (see Figure 11). The adjustment scale (PG)
indicates the factory-set outlet pressure (see Figure 10), which can be
adjusted using the hexagonal tool provided (or an acceptable Allen
wrench) to obtain the desired servo pressure regulator performance and
timing characteristics.
P
G
P
ST
3 to 12 Seconds
Time
(
s
)
P
G
Figure 11: Servo Pressure Regulator Performance vs.
Timing Characteristics
Cycle the valve three times to check for proper performance, leaving a
minimum time of 20 seconds between cycles to evacuate the pressure
chamber.
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 15
This valve provides mechanical modulating control of the gas outlet
pressure at a consistent ratio to the main air blower pressure. An example
of a typical installation is shown in Figure 12. The burner control responds
to a higher demand for heat by increasing the amount of air being supplied
to the burner, resulting in an increased air pressure. With the air pressure
(PA) connected to the valve, the valve seat position is controlled to achieve
the optimum outlet gas pressure according to the preset gas/air ratio.
The combustion chamber pressure (PF) can be connected to improve
combustion quality in cases where the combustion chamber pressure is
significantly higher during operation than atmospheric pressure.
M
P
G
P
A
P
F
Gas
Line
Manual
Shutoff
Valve
Optional
Pressure
Switch
Filter/
Strainer
Air Line
GM Series Combination Control
Solenoid
Valve Workin
g
with Controller
Gas/Air
Controller
Boiler
Solenoid
Valve
Figure 12: Typical Application Installation
The valve not only allows a gas/air ratio adjustment, but also an offset
adjustment (zero set), which allows for fine adjustment at lower ratios.
With these adjustments, the outlet valve pressure (PG) calculates to:
PG= R • PA+ Z without combustion chamber pressure PF
PG- PF= R • (PA- PF) + Z with combustion chamber pressure PF
GM-4_6_
(Dual On/Off
with Gas/Air
Ratio Control)
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16 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
To adjust the valve, first check the factory settings. The adjustments for
the gas/air ratio (R scale) and zero set (Z scale) are located on both sides of
the gas/air ratio control module (see Figure 13). The factory settings are:
xGas/air ratio (R): 1:2
xZero set (Z): 0
Z
0
-+
R
1
0,6
23
4
5
6
Figure 13: Zero Set and Gas/Air Ratio Adjustments
Before starting the burner, make sure that the gas/air ratio and zero set
settings are correct for the specific appliance. If necessary, use the
hexagonal tool provided (or an acceptable Allen wrench) to adjust these
settings to the appliance manufacturer’s recommendations. If the specific
ratio settings are not available, ensure that the appliance is safe to operate
at the factory settings.
Start the burner and gradually increase the output of the valve. If the
burner does not light, check for a flame during the ignition phase. If the
flame extinguishes immediately, the system may have excess air. Check
again and adjust the gas/air ratio (R) setting if necessary.
With the burner in the maximum output position, adjust the gas/air ratio
(R scale) to meet the desired flue gas analysis readings. The ratio (R) of
gas outlet pressure (PG) to combustion air pressure (PA) is adjustable within
a range of 0.6:1 to 6:1 (see Figure 14).
Check the flue gas analyses on low and high output settings without
manipulating the adjustments. Once the readings have been checked, fine
tune (by adjusting the zero set) the settings if necessary. In cases where
combustion chamber pressure (PF) is used, connect it and repeat the gas/air
ratio (R) adjustment.
Gas/Air Ratio (R)
Adjustment
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 17
Z0.6:1
0.7:1
1:1
2:1
3:1
5:1
6:1
004812 16 20
4
8
12
16
20
P
A
(
in. W.C.
)
P
A
- P
F
(
in. W.C.
)
P
G
(
in. W.C.
)
P
G
- P
F
(
in. W.C.
)
Figure 14: Analyses Chart
With the correct gas/air ratio (R) set, there may be some minor deviations
(caused by friction, etc.) at very low pressures. To allow for fine
adjustment of the valve, the zero set can be changed. The zero set adds a
constant offset to the flue gas analyses, affecting the low output figures
more significantly than the high output figures.
Zero set (Z) can be accomplished by a parallel shift of the characteristic
curve from -2 to +2 mbar (-0.8 to +0.8 in. W.C.) (see Figure 14).
Set the burner to the low fire position, perform a flue gas analysis, and
vary the outlet pressure by adjusting the Z scale until the desired flue gas
analysis readings are obtained.
If adjusting the zero set (Z) results in an unacceptable high output figure,
repeat the adjustments starting with the gas/air ratio (R) adjustment
procedure.
Zero Set (Z)
Adjustment
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18 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
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G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 19
Repairs and Replacement
Field repairs must not be made, except to replace the filter or strainer. For
a replacement part, contact the nearest Johnson Controls representative or
the original equipment manufacturer.
!
CAUTION: Label all wires prior to disconnection when servicing
valves. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
Perform the following steps to replace the filter or strainer.
1. Clean or replace the filter or strainer with each recommended
inspection or at a minimum each annual functional inspection.
2. Close the main manual shutoff valve and disconnect field wiring. As
each wire is disconnected, label it with the correct terminal
designation.
3. Remove the screws on the flanges and remove the valve and filter
plate.
4. Clean or replace the filter or strainer. Reinstall the filter plate and
valve.
5. Refasten the flange screws to the valve and reconnect field wiring.
!
WARNING: Fire or explosion hazard. Verify that the valve
functions properly and there are no gas leaks. Follow
this checkout procedure before leaving the installation.
Failure to verify proper valve installation, equipment
operation, and gas tight connections may result in fire,
explosion, property damage, and injuries or death.
6. Open the pressure connection between the manual shutoff valve and
the GM valve.
7. Connect air tubing with a maximum pressure of 1-1/2 times the
valve’s maximum operating pressure (as indicated on the valve) to the
opened pressure connection.
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20 G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin
8. Paint the pipe connections and flanges of the valve with a rich soap
and water solution.
If bubbles occur, this is an indication of a leak. To stop a leak, tighten
joints and pipe connections. Replace the part if the leak cannot be
stopped.
If bubbles do not occur, remove the air tubing and close the upstream
pressure connection.
9. Open the main manual shutoff valve.
10. Observe at least three complete operating cycles to ensure that all
components are functioning correctly.
Controls Group www.johnsoncontrols.com
507 E. Michigan Street FAN 121
P.O. Box 423 Installation Sheets Manual
Milwaukee, WI 53201 Printed in U.S.A.
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