Lennox EL296UHE Series Unit Information page 13

Code Diagnostic Codes/Status of Equipment
E270 Soft lockout - Exceeded maximum number of
retries. No flame current sensed.
E271 Soft lockout - Exceeded maximum number of
retries. Last retry failed due to the pressure
switch opening.
E272 Soft lockout - Exceeded maximum number
of recycles. Last recycle due to the pressure
switch opening.
E273 Soft lockout - Exceeded maximum number of
recycles. Last recycle due to flame failure.
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.
E275 Soft lockout - Flame sensed out of sequence.
Flame signal is gone.
E290 Ignitor circuit fault - Failed ignitor or triggering
circuitry.
TABLE 4 Continued
Action Required to Clear and Recover
Check for proper gas flow. Ensure that ignitor is lighting burner.
Check flame sensor current. Clears when heat call finishes
successfully.
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.
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.
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.
Shut down system. 1-hour soft lockout. Check firing rate and
air flow. Check for blockage. Clears when heat call finishes
successfully.
Shut off gas. Check for gas valve leak. 1-hour soft lockout. Clears
when flame has been proven stable.
Measure resistance of hot surface ignitor. Replace if open or not
within specifications. 1-hour soft lockout. Clears when flame has
been proven stable.
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