Lennox Unit controller

Lennox Error Code 22

Unit controller

What It Means

  • LOW PRESSURE SWITCH COMPRESSOR 1

Causes & actions from Lennox

How it shows
  • M4 alarm code: 22

Compressor is off. Check charge, fans and coil. Use service menu to clear lockouts.

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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