24 Volt Honeywell Control Service
Some heaters covered by this manual come equipped with
a 24 volt vent damper and a Modular Honeywell Gas
Control. Both the Electronic Control Module and the Valve
Module of this control may be changed without the need to
disconnect the threaded control fitting from the body of the
water heater. Almost all gas valve failures will be corrected
by replacing the Electronic Control Module (ECM). If replac-
ing the ECM does not correct the problem, contact GSW
technical service at 1-888-479-8324 or online at techsup-
[email protected].
Electronic Control Module Replacement
Do not remove the entire gas control assembly from the
water heater. To remove the Electronic Control Module:
1.
Remove the front Torx screw at the bottom of the gas
control as illustrated in Figure 27.
2.
Use a flat-blade screwdriver to release the two tabs at
the top of the gas control and lift the electronic control
straight up (see Figures 28 & 29).
3.
Disconnect the temperature sensor cable.
Note:
When removing the control module from the gas con-
trol assembly, care is required to disengage the pins on the
valve module.
4.
Re-assemble in the reverse order.
Note:
Care is required to align the pins on the valve module
to their proper location in the control module during re-
assembly.
Valve Module Replacement
Do not remove the entire gas control assembly from the
water heater. To remove the Valve Module:
1.
Remove the Electronic Control Module as outlined
above.
Note:
When removing the control module from the gas con-
trol assembly, care is required to disengage the pins on the
valve module.
2.
Remove the screw and the ground tab with a Torx
screwdriver (see Figure 30).
3.
Insert a flat-blade screwdriver between the casting and
the locking tabs at the bottom of the valve.
4.
Carefully pry against the casting until it barely slides
past the locking tab edge.
5.
Repeat on the opposite side.
6.
Replace the valve.
Note:
Use caution when replacing the valve to not apply
pressure with the hand on the valve pins.
7.
Re-assemble in the reverse order.
Note:
Care is required to align the pins on the valve module
to their proper location in the control module during re-
assembly.
– 24 –
Figure 27
Disassembly Step 1
FRONT TORX
SCREW
Figure 28
Disassembly Step 2
TABS
DISCONNECT
TEMPERATURE
SENSOR CABLE
HERE
ELECTRONIC
CONTROL
MODULE
THREADED CONTROL
FITTING
(DO NOT REMOVE
FROM WATER HEATER)
