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TABLE 4 Continued
Code
Diagnostic Codes/Status of Equipment
Action Required to Clear and Recover
E270
Soft lockout - Exceeded maximum number of
retries. No flame current sensed.
Check for proper gas flow. Ensure that ignitor is lighting burner.
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 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
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. Clears when heat call
finishes successfully.
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.
E290
Ignitor circuit fault - Failed ignitor or triggering
circuitry.
Measure resistance of hot surface ignitor. Replace if open or not
within specifications. 1-hour soft lockout. Clears when flame has
been proven stable.
