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31-5000724 Rev. 0
Code
Diagnostic Codes / Status of Equipment
Action Required to Clear and Recover
E240
Low flame current - Run mode- Refer to
troubleshooting
Check micro-amperes of flame sensor using control
diagnostics or field 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 off 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 firing rate on furnace. Ensure there
is no blockage in heater. Check for proper air flow. 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 airflow and input rate. Clear
when heat call is finished.
E270
Soft lockout - Exceeded maximum number of
retries. No flame current sensed.
Check for proper gas flow. Ensure that igniter is lighting
burners. Check flame sensor current. Clears when heat
call finishes 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 finishes 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 finishes successfully.
E273
Soft lockout - Exceeded maximum number of
recycles. Last recycle due to flame failure
Check micro-amperes of flame sensor using control
diagnostics or field 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 firing rate
and air flow. Check for blockage. Clears when heat call
finishes successfully.
E275
Soft lockout - Flame sensed out of sequence.
Flame signal is gone.
Shut off gas. Check for gas valve leak. 1-hour soft
lockout. Clears when flame has been proven stable.
E276
Soft lockout calibration failure.
Unable to perform pressure switch calibration. Check
vent system and pressure switch wiring connections.
1-hour soft lockout. Clears when calibration has finished
successfully.
E290
Ignitor circuit fault - Failed ignitor or triggering
circuitry.
Measure resistance of hot surface igniter. Replace if
open or not within specifications. 1-hour soft lockout.
Clears when flame has been proven stable.
E291
Heat airflow restricted below the minimum.
Check for dirty filter and airflow restriction. Check
blower performance. 1-hour soft lockout. Cleared when
heat call finishes successfully.