Allied A96US2V - Integrated Control Diagnostic Codes (E227-E290)

507404-02Page 70 of 80 Issue 1448
Integrated Control Diagnostic Modes (Continued)
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 re IFC switched to high re ignition because low re pressure switch did
not close in allowed time. No action is needed.
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 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 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 com-
bustion 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 off 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 sys-
tem and pressure switch wiring connections. 1-hour so 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 so lockout. Clears when ame has
been proven stable.