34
Servicing should only be performed by a Quali
fi
ed Service Technician
FAULT
CAUSE
CORRECTIVE ACTION
Flame Sequence
The
fl
ame detector circuit is
seeing a
fl
ame signal while
no
fl
ame is present.
• Check supply voltage for proper
polarity.
• Check external wiring for voltage
feedback.
• Check
the
fl
ame rod and make sure
it is clean. Inspect
fl
ame sensor for
damage and replace as needed.
• Check the internal wiring for bad
connections.
• Replace main control board.
Outlet ARHL
The outlet water
temperature has exceeded
the setting of the automatic
reset high limit.
• Verify that the system is full of water
and that all air has been properly
purged from the system.
• Verify that the water heater is piped
properly into the system. Refer to the
Instruction Manual for proper piping
methods.
• Check 120 vac to water heater pump
motor on a call for heat. If voltage is
not present, check wiring back to the
main control board.
• Replace the main control board if
necessary.
• If 120 vac is present on a call for
heat and the water heater pump is
not operating, replace the pump.
• If the manual reset high limit has
tripped, check setting of the device.
• Check resistance of water sensors
and compare to Table 11.1
mentioned on Page 38. Replace
sensor if necessary.
Table 10. Troubleshooting Chart - Fault Messages Displayed on UIM (Continued.)
Tank Temperature
64°F
Operating Setpoint
185°F
S t a t u s : F l a m e F a i l : I g n i t i o n
HELP
RESET
A. O. Smith XP
MENU
Tank Temperature
73°F
Operating Setpoint
185°F
S t a t u s : O u t l e t A R H L
HELP
RESET
A. O. Smith XP
MENU