Lennox SLP98UHV Installation Instructions Manual page 56

Integrated Control Diagnostic Codes (continued)
Code
Low pressure switch failed open - Refer to troubleshooting in installation instruc­
E 223
tion.
Low pressure switch failed closed - Refer to troubleshooting in installation instruc­
E 224
tion.
E 225 High pressure switch failed open - Refer to troubleshooting in installation instruc­
tion.
E 226 High pressure switch failed closed - Refer to troubleshooting in installation instruc­
tion.
E 227 Low pressure switch open during trial for ignition or run mode. Refer to trouble­
shooting in installation instruction.
E 228 Unable to perform successful pressure switch calibration.
Low flame current - Run mode - Refer to troubleshooting in installation instruction.
E 240
Flame sensed out of sequence - Flame still present.
E 241
E 250 Limit switch circuit open - Refer to troubleshooting in installation instruc­
tion.
Discharge air temperature too high (gas heat only).
E 252
E 270 Soft lockout - Exceeded maximum number of retries. No flame current
sensed.
E 271 Soft lockout - Exceeded maximum number of retries. Last retry failed due
to the pressure switch opening.
E 272 Soft lockout - Exceeded maximum number of recycles. Last recycle due
to the pressure switch opening.
Soft lockout - Exceeded maximum number of recycles. Last recycle due
E 273
to flame failure.
E 274 Soft lockout - Exceeded maximum number of recycles. Last recycle
failed due to the limit circuit opening or limit remained open longer than
3 minutes.
E 275 Soft lockout - Flame sensed out of sequence from code 241 fault. Flame
signal is gone.
E 276 Soft lockout - Exceeded maximum number of calibration retries.
E 290 Ignitor circuit fault - Failed ignitor or triggering circuitry.
Restricted air flow - Cubic feet per minute is lower than what is needed
E 291
for minimum firing rate.
Indoor blower motor unable to start - Seized bearings, stuck wheel, etc.
E 292
E 294 Combustion air inducer motor amp draw is too high.
Diagnostic Codes/Status of Equipment
Check inches of water column pressure during operation
of low pressure switch on heat call, measure inches of
water column of operating pressure, inspect vent and com­
bustion air inducer for correct operation and restriction.
Check low pressure switch for closed contacts, measure
inches of water column of operating pressure, inspect vent
and combustion air inducer for correct operation and re­
striction.
Check inches of water column pressure of high pressure
switch on heat call, measure inches of water column of
operating pressure, inspect vent and combustion air induc­
er for correct operation and restriction.
Check high pressure switch for closed contacts, measure
inches of water column of operating pressure, inspect vent
and combustion air inducer for correct operation and re­
striction.
Check inches of water column pressure during operation
of low pressure switch on heat call, measure inches of
water column of operating pressure, inspect vent and com­
bustion air inducer for correct operation and restriction.
Retry after 300 seconds. Error counter cleared when exit­
ing lockout, unable to perform pressure switch calibration.
Check vent system and pressure switch wiring connec­
tions.
Check micro amperes of flame sensor, clean or replace
sensor. Measure voltage of neutral to ground for good unit
ground.
Shut off gas, check for gas valve leak.
Check why limit is tripping, overfired, low air flow.
Check temperature rise, air flow and input rate.
Check for gas flow, ignitor lighting burner, flame
sensor current.
See E 223.
See E 223 and E 225.
See E 240.
See E 250.
See E 241.
See E 228.
See E 207.
Check for dirty filter, unit air flow restriction, blower
performance.
Indoor blower motor unable to start (seized bearing,
stuck wheel, etc), replace motor or wheel if assem­
bly does not operate or meet performance.
Check combustion blower bearings, wiring , am­
peres, replace if it does not operate or meet perfor­
mance.
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Action Required to Clear and Recover