Gas Valve Failure; Communication Failure - State Water Heaters GP650 HTPDT Service Handbook

ULTRA HIGH EFFICIENCY POWER VENT/POWER DIRECT VENT - SERVICE MANUAL
FAULT MESSAGES (CONT)
DISPLAYED MESSAGE
CONDITION/INDICATES

"Gas Valve Failure"

The control system has not detected any current
through the gas valve after it has been energized.

"Communication Failure"

Loss of communication between the CCB and the
UIM.
Technical Literature Department
Servicing should only be performed by a Qualified Service Agent
• Turn off power - check all wiring and connectors
between the CCB's J6 Socket (page 35) pins 2
& 15 and the Gas Valve's solenoid coil. Repair/
replace anything worn or damaged as neces-
sary.
• Perform close visual inspection of the pins
inside the CCB J6 plug and socket - ensure
plugs and sockets are mating properly and pro-
viding good contact. Repair/replace anything
worn or damaged as necessary.
• Turn off power - disconnect the Gas Valve wir-
ing plug on top of the Gas Valve solenoid coil.
Check Gas Valve solenoid coil resistance with
an ohm meter at the solenoid coil terminals.
Normal resistance is approximately 7 million
ohms. If the Gas Valve solenoid coil is an open
circuit - replace the Gas Valve.
• Check for 24 VAC at CCB's J6 Socket pins 2 &
15 during the Ignition Activation operating state
(the Gas Valve status icon will be visible on the
UIM display during this period.
• Call the technical support phone number shown
on the water heater labeling for further assis-
tance if the problem has not been corrected
after performing the procedures outlined here.
• Turn off power - check the communication cable
connections between the J2 Socket on the UIM
circuit board (page 27) and the CCB J16 Port
(page 35).
• Try a new communication cable (standard cate-
gory V network cable) between the CCB and the
UIM.
• Call the technical support phone number shown
on the water heater labeling for further assis-
tance if the problem has not been corrected
after performing the procedures outlined here.
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CHECK/REPAIR
Ashland City, TN © 2008