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Integrated Control Diagnostic Modes
Code
Diagnostic Codes/Status of Equipment
Action Required to Clear and Recover
E271
Soft lockout - Exceeded maximum number of re-
tries. Last retry failed due to the pressure switch
opening.
Check pressure (inches w.c.) of low pressure switch clos-
ing on heat call. Measure operating pressure (inches w.c.).
Inspect vent and combustion air inducer for correct oper-
ation and restriction. Clears when heat call finishes suc
-
cessfully.
E272
Soft lockout - Exceeded maximum number of re-
cycles. Last recycle due to the pressure switch
opening.
Check operation of low pressure switch 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 (inches w.c.). Inspect vent and combustion air
inducer for correct operation and restriction. Clears when
heat call finishes successfully.
E273
Soft lockout - Exceeded maximum number of re-
cycles. Last recycle due to flame failure.
Check micro-amperes of flame sensor using control diag
-
nostics or field-installed mode. Clean or replace sensor.
Measure voltage of neutral to ground to ensure good unit
ground. Clears when heat call finishes successfully.
E274
Soft lockout - Exceeded maximum number of re-
cycles. Last recycle failed due to the limit circuit
opening or limit remained open longer than 3 min-
utes
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
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 finished successfully.
E290
Ignitor circuit fault - Failed ignitor or triggering cir-
cuitry.
Measure resistance of hot surface ignitor. Replace if open
or not within specifications. 1-hour soft lockout. Clears
when flame has been proven stable.
E291
Heat air flow restricted below the minimum.
Check for dirty filter and air flow restriction. Check blower
performance. 1-hour soft lockout. Cleared when heat call
finishes successfully.
E292
Indoor blower motor unable to start due to ob-
structed 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 lock-
out. Clears after circulator successfully starts.
E294
Combustion air inducer over current.
Check combustion blower bearings, wiring and amps. Re-
place 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. Re-
place if necessary. Cleared after blower demand is satis-
fied.
E310
Discharge error temperature sensor failure. Only
shown if shorted or
out of range.
Compare outdoor sensor resistance to temperature/ re-
sistance charts in installation instructions. Replace sensor
if necessary. Cleared in Communicating mode: 30 sec-
onds after fault recovered. In Non- Communicating mode:
Cleared after the current heat call is completed.
E311
Heat rate reduced to match indoor blower air flow.
Warning Only. Furnace blower in cutback mode due to
restricted airflow. Reduce firing rate every 60 seconds to
match available CFM. Check filter and duct system. To
clear, replace filter if needed or repair/ add duct. 2-stage
controls will reduce firing rate to 1st stage. Clears when
heat call finishes successfully.
