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31-5000734 Rev. 0
Code
Diagnostic Codes / Status of Equipment
Action Required to Clear and Recover
E227
Low pressure switch open during trial for ignition
or run mode. Refer to troubleshooting
Check operation 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. Resumes normal operation after fault is
cleared.
E228
Combustion air inducer calibration failure
Unable to perform pressure switch calibration. Check
vent system and pressure switch wiring connections.
Resumes normal operation after fault is cleared
E229
Ignition on high fire
IFC switched to high fire ignition because low fire
pressure switch did not close in allowed time. No action
is needed.
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.
