Error code reference

Lennox Heat Pump Error Code Alternating SLOW Flash

5-minute anti-short cycle delay (initial power up, safety trip, or end of room thermostat demand).

SourceLennox XP14 Series Heat Pump - Full Service Manualp. 9

Diagnostic procedure

The full Alternating SLOW Flash procedure

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MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

None required (Jumper TEST pins to override).

SourceLennox XP14 Series Heat Pump - Full Service Manualp. 9

Unlock with pass

More steps, wiring diagram references, and verified part numbers

Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.

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Where this code is documented

1 manual in the MyPros+ library documents this code for Lennox heat pump.

Models covered by the manuals that document this code

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The full Alternating SLOW Flash procedure

Where this code is documented

Models covered by the manuals that document this code

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