36
Servicing should only be performed by a Quali
fi
ed Service Technician
FAULT
CAUSE
CORRECTIVE ACTION
Inlet Sensor Short
The inlet water temperature
sensor has been shorted.
• Check the Inlet Sensor and its
associated wiring. Repair or replace
the sensor or wiring if damaged.
• Measure the resistance of the sensor
and compare the resistance to Table
11 on Page 38.
• Replace the sensor if necessary.
Damper Proving SW
An optional remote proving
switch is not making.
• Check function of remote devices.
• Check for loose or misplaced jumper
if auxiliary proving switch is not
installed.
Flue Temp Limit
The
fl
ue temperature
reaches 240 deg.
• Check for proper water
fl
ow.
• Check for faulty
fl
ue sensor. Replace
fl
ue sensor if necessary.
• Measure the resistance of the sensor
and compare the resistance to Table
11.2 on Page 38.
Outlet Temp Drift
The outlet temp thermistor
has exceeded the 10
degree drift limit.
• Check wiring connections to the
thermistor.
• Check wiring connections to the
main control board.
• Measure the resistance of the sensor
and compare the resistance to Table
11.1 on Page 38.
Table 10. Troubleshooting Chart - Fault Messages Displayed on UIM (Continued.)
Tank Temperature
73°F
Operating Setpoint
185°F
S t a t u s : I n l e t S e n s o r S h o r t
HELP
RESET
A. O. Smith XP
MENU
Tank Temperature
84°F
Operating Setpoint
135°F
S t a t u s : D a m p e r P r o v i n g S W
HELP
RESET
A. O. Smith XP
MENU
Tank Temperature
65°F
Operating Setpoint
185°F
S t a t u s : F l u e Te m p L i m i t
HELP
RESET
A. O. Smith XP
MENU
Tank Temperature
144°F
Operating Setpoint
135°F
S t a t u s : O u t l e t Te m p D r i f t
HELP
RESET
A. O. Smith XP
MENU