Lennox Split & Multi-Split

Lennox Error Code RED ON

Split & Multi-Split:

What It Means

  • Thermostat demand exists but no current tocompressor detected.

Causes & actions from Lennox

How it shows
  • lsom trip led: RED ON (trip: on)

Indicates there is a demand signal from the thermostat but no current to the compressor is detected by the module.

Applicable models & manual sources
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.

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