Error code reference

Lennox Heat Pump Error Code DS2 OFF / DS1 SLOW Flash

Low pressure fault: pressure switch has tripped (1 strike counted).

SourceLennox XP14 Series Heat Pump - Full Service Manualp. 9

Diagnostic procedure

The full DS2 OFF / DS1 SLOW Flash procedure

Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.

MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

1) Remove any blockages or restrictions from coils and/or fans; check indoor and outdoor fan motor for proper current draws. 2) Check system charge using approach & subcooling temperatures. 3) Check system operating pressures and compare to unit charging charts. 4) Make sure all pressure switches and sensors have secure connections.

SourceLennox XP14 Series Heat Pump - Full Service Manualp. 9

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

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Where this code is documented

2 manuals in the MyPros+ library document this code for Lennox heat pump.

Models covered by the manuals that document this code

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The full DS2 OFF / DS1 SLOW Flash procedure

Where this code is documented

Models covered by the manuals that document this code

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