Allied A80US2V - Page 13

508155-01 Issue 2108 Page 13 of 49
Code Diagnostic Codes / Status of Equipment Action Required to Clear and Recover
E240 Low ame current - Run mode- Refer to
troubleshooting
Check micro-amperes of ame sensor using control diagnostics or eld
installed mode. Clean or replace sensor. Measure voltage of neutral to
ground to ensure good unit ground. Alert clears after current heat all has
been completed.
E241 Flame sensed out of sequence-Flame still
present.
Shut o󰀨 gas. Check for gas valve leak. Replace if necessary. Alert clears
when fault is recovered.
E250 Limit switch circuit open - Refer to
troubleshooting.
Check for proper ring rate on furnace. Ensure there is no blockage in
heater. Check for proper air ow. If limit not closed within 3 minutes unit
will go into 1 hour soft lockout. Resumes normal operation after fault is
cleared.
E252 Discharge air temperature too high (gas heat
only).
Check temperature rise airow and input rate. Clear when heat call is
nished.
E270 Soft lockout - Exceeded maximum number of
retries. No ame current sensed.
Check for proper gas ow. Ensure that igniter is lighting burners. Check
ame sensor current. Clears when heat call nishes successfully.
E271 Soft lockout - Exceeded maximum number of
retries. Last retry failed due to the pressure switch
opening.
Check pressure (inches w.c.) of low pressure switch closing on heat call.
Measure operating pressure (inches w.c.). Inspect vent and combustion
air inducer for correct operation and restriction. Clears when heat call
nishes successfully.
E272 Soft lockout - Exceeded maximum number of
recycles. Last recycle due to the pressure switch
opening
Check operation of low pressure to see if it is stuck closed on heat call.
Check pressure (inches w.c.) of high pressure switch closing on heat call.
Measure operating pressure. Inspect vent and combustion air inducer
for correct operation and restriction. Clears when heat call nishes
successfully.
E273 Soft lockout - Exceeded maximum number of
recycles. Last recycle due to ame failure
Check micro-amperes of ame sensor using control diagnostics or eld
installed mode. Clean or replace sensor. Measure voltage of neutral to
ground to ensure good unit ground. Alert clears after current heat call has
been completed.
E274 Soft lockout - Exceeded maximum number of
recycles. Last recycle failed due to the limit circuit
opening or limit remained open longer than 3
minutes.
Shut down system 1-hour soft lockout. Check ring rate and air ow.
Check for blockage. Clears when heat call nishes successfully.
E275 Soft lockout - Flame sensed out of sequence.
Flame signal is gone.
Shut o󰀨 gas. Check for gas valve leak. 1-hour soft lockout. Clears when
ame has been proven stable.
E276 Watchguard calibration failure. Unable to perform pressure switch calibration. Check vent system and
pressure switch wiring connections. 1-hour soft lockout. Clears when
calibration has nished successfully.
E290 Ignitor circuit fault - Failed ignitor or triggering
circuitry.
Measure resistance of hot surface igniter. Replace if open or not within
specications. 1-hour soft lockout. Clears when ame has been proven
stable.
E291 Heat airow restricted below the minimum. Check for dirty lter and airow restriction. Check blower performance.
1-hour soft lockout. Cleared when heat call nishes successfully.
E292 Indoor blower motor unable to start due to
obstructed wheel seized bearings.
Indoor blower motor unable to start (seized bearing, stuck wheel,
etc.) Replace motor or wheel if assembly does not operate or meet
performance standards. 1-hour soft lockout. Clears after circulator
successfully starts.
E294 Combustion air inducer over current. Check combustion blower bearings wiring and amps. Replace if does not
operate or does not meet performance standards. Clears after inducer
current is sensed to be in-range after the ignition following the soft lockout
or reset.
E295 Indoor blower motor temperature is too high. Indoor blower motor over temperature (motor tripped on internal
protector). Check motor bearings and amps. Replace if necessary.
Cleared after blower demand is satised.
E310 Discharge error temperature sensor failure. Only
shown if shorted or out of range.
Compare discharge sensor resistance to temperature resistance charts
in installation instructions.. Replace sensor if necessary. Cleared
in Communicating mode 30 seconds after fault recovered. In Non-
Communicating mode cleared after the current heat call is completed.
Table 5. Integrated Diagnostic Codes/Status of Equipment