Westinghouse WGRGH20**75F Series Installation, Start-Up, Maintenance, Parts, Warranty page 45

Problem
It takes a long time before hot
water flows from the faucet
The water is not hot enough
The water at the faucet is too hot
A fan can be heard even when the
unit is not operating
White "smoke" can be seen coming
out of the exterior exhaust gas
vent
Table 28 - Troubleshooting Chart
DIAGNOSTICS AND SUGGESTED CORRECTIVE ACTIONS
The water heater control is able to record information about the water heater's condition at the time of the ten previous faults or errors. This
information is available to view in the Installer Mode under the History screen.
The following screens may be displayed when reviewing the water heater history. The table below also includes diagnostic information and
possible corrective actions.
Display
Nothing appears on the
display control panel but
the fan runs at full speed
Nothing appears on the
display control panel
and no other water
heater components are
operating
Nothing appears on the
display control panel,
but the water heater is lost from the control
operating
Display repeatedly goes Occurs when control
through initialization
sequence
Table 29 - Diagnostics and Suggested Corrective Actions
Possible Causes
Is the faucet some distance from the water heater?
Is the water temperature on the thermostatic
mixing valve set too low?
Is the water temperature on the thermostatic
mixing valve set too high?
1. The fan continues to operate after the burner
shuts off to clear the exhaust vent of combustion
gases.
2. The fan may run to help prevent freezing.
Depending on the outside temperature, water
vapor can be produced as the exhaust is vented.
Condition
Check wiring for short circuit or incorrect
wiring
Control is not
receiving power
Check 5P wire connection to the Fan Motor
per wiring diagram
Ensure service switch and/or circuit
breaker to water heater is turned ON
Is there 120V at the service switch
Is the ON/OFF switch inside the water
Control is not heater cabinet is turned on
receiving 120V
Check for 120V at the line voltage terminal
power
block located inside the water heater
cabinet
Inspect the fuse. Replace as necessary
Check for loose connections and proper
pin alignment / engagement on the
Occurs when
control's plug
communications is
Cycle power off and on using water heater
to the display
power switch and check for operation
Cycle power off and on using appliance
does not receive
power switch and check for operation
signal from fan
1. Allow time for the cold water already in the
pipes to flow from the faucet.
2. Have recirculation valves and/or plumbing
return line(s) installed and program the unit for
recirculation.
Adjust the temperature setting.
1. This is normal operation – no action is
required.
2. Protect the water heater from freezing
temperatures or shut off and drain the unit.
This is normal operation – no action is required.
Diagnostic
Correct wiring per wiring diagram
including connection of transformer to
the control.
Push the Power button on the control
panel
Turn on service switch or circuit breaker to
power water heater
Troubleshoot and correct the power
supply to the manual switch
Turn ON the manual power switch inside
the water heater cabinet
Correct wiring inside the water heater
cabinet using the wiring diagram in the
installation manual
Replace the fuse with the proper part
found in the replacement part section of
this manual. If fuse blows again, recheck
the wiring per diagram
Check for continuity on the wire harness
from the display to the control. See repair
parts section for proper replacement part.
Replace with new display module.
See repair parts section for proper
replacement part.
Replace fan
Possible Remedies
Possible Corrective Actions
whl-605 Rev. 002 Rel. 000 Date 1.23.19
45