Alarm Codes - Lennox icomfort Setup Manual

Alarm ID Message Name
241 Flame Out of Sequence − Still Present
250 Primary Limit Switch Open
252 Discharge Air Temperature High
270 Watch Guard − Flame Failure on Ignite
271 Watch Guard − Low Pressure Switch Open
272 Watch Guard − Low Pressure Switch Open Run
Mode
273 Watch Guard − Flame Fail in Run Mode
274 Watch Guard − Primary Limit Switch Open
275 Watch Guard − Flame Out of Sequence. No
Flame
276 Watch Guard − Calibration Failure
290 Ignition Circuit Problem
291 Heat Airflow Restricted Below Min.
292 Indoor Blower Motor Start Problem
294 Inducer Motor Over current
295 Indoor Blower Over Temperature
310 Discharge Air Sensor Problem
311 Heat Rate Reduced to Match Airflow
312 Reduced Airflow − Indoor Blower Cutback
Alarm Codes and Troubleshooting
Action required to Clear/Recover
Shut off gas, check for gas valve leak.
Check firing rate on furnace, blockage in heater, and air flow.
Check temperature rise, air flow and input rate.
Check for gas flow, ignitor lighting burner, flame sensor current.
Check inches of water column closing pressure of low pressure switch on heat call, measure inches of water
column of operating pressure, inspect vent and combustion air inducer for correct operation and restriction.
Check operation of low pressure switch for stuck closed on heat call, measure inches of water column of oper-
ating pressure, inspect vent and combustion air inducer for correct operation and restriction. Check inches of
water column closing pressure of high pressure switch on heat call, measure inches of water column of operat-
ing pressure, inspect vent and combustion air inducer for correct operation and restriction.
Check micro amperes of flame sensor in board diagnostics or field installed mode; clean or replace sensor.
Measure voltage of neutral to ground for good unit ground.
Check why limit is tripping, over fired, low air flow.
Shut off gas, check for gas valve leak.
Unable to perform pressure switch calibration. Check vent system and pressure switch wiring connections.
Measure resistance of Hot Surface Ignition ignitor, replace if open or not within specification; otherwise replace
control.
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 assembly
does not operate or meet performance.
Check combustion blower bearings, wiring, amps. Replace if does not operate or meets performance.
Indoor blower motor over temperature (motor tripped on internal protector). Check motor bearings, amps; re-
place if necessary.
Compare outdoor sensor resistance to temperature/resistance charts in installation instructions. Replace sensor
if necessary.
Furnace blower in cutback mode due to restricted airflow. Check filter and ductwork. To clear, replace filter if
needed or repair/add ductwork.
Restricted airflow − Indoor blower is running at a reduced CFM (Cutback Mode − The variable speed motor has
pre−set speed and torque limiters to protect the motor from damage caused by operating out of its designed
parameters (0 to 0.8" w.g. total external static pressure). Check filter and ductwork. To clear, replace filter if
needed or repair/add ductwork.
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icomfortt Touch Screen 7−Day Programmable Thermostat