Communication Failure - State Water Heaters 120 Series Service Handbook

fault messages
displayed message/condition/indicates
Ignition Failure
The Control System has detected less than 1.0 μA (dC
micro amps) through the flame sensor during the Ignition
Verification operating state on three consecutive trials for
ignition.
Ignition Failure
Fault occurred 2 mins ago
The water heater has failed to
ignite the burner.
Call a service professional:
Your Company Name Here
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CHANGE
Important Service Reminder:
When performing any troubleshooting steps outlined in
this manual always consider the wiring and connectors
between components. Perform a close visual inspection
of all wiring and connectors to a given component before
replacement.

Communication Failure

The Control System has detected a loss of communications
between the CCB and the uIM.
Communication Failure
Fault occurred 2 mins ago
Communications between the
user interface module and the
central control board could not
be established.
Call a service professional:
Your Company Name Here
(press [DOWN] for more....)
CHANGE
66
BACK ADVANCED
BACK ADVANCED
Servicing should only be performed by a Qualified Service Agent
possible causes - checK/repair
• Check for flame sensing current during the Ignition
Verification operating state. Perform the Flame
Sensing Current Test on page 19.
• The Combustion Blower and Burner Assembly must
be removed to access the Burner, Flame Sensor
and the Igniter. If the preceding checks have failed
to identify the cause for the Ignition Failure, remove
the Burner Assembly for a thorough inspection. See
Figure 5 on page 9 and Combustion Blower and
Burner Removal on page 14.
Ensure the Blower discharge orifice is installed
properly in the top of the Burner Adapter during
disassembly, see Figure 11 on page 13.
Clean the Flame Sensor with fine steel wool - check for
signs of excessive wear, bent, damage, cracks in the
insulator - replace Flame Sensor if worn or damaged.
Check/adjust the gap between the Flame Sensor and
the Burner, this gap should be approximately 1/2 inch.
See Flame Sensor on page 18.
Inspect the Burner Adapter wiring harness for signs of
wear or damage. Repair/replace as necessary.
Remove the Burner from the end of the Burner
adapter and check for any debris that may be clogging
the Burner. If the Burner is clogged with debris or
damaged, replace the Burner.
• Call the toll free support phone number on the back
cover of this manual for further assistance 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 and the J16 Port on the CCB, see uIM
(user Interface Module) on page 37 and CCB (Central
Control Board) on page 39.
• Replace the communication cable (standard category
V network cable) between the CCB and the uIM.
• Call the toll free support phone number on the back
cover of this manual for further assistance if the
problem has not been corrected after performing the
procedures outlined here.