Lennox Unit controller

Lennox Error Code 190

Unit controller

What It Means

  • INVERTER COMMUNICATION ERROR

Causes & actions from Lennox

How it shows
  • M4 alarm code: 190

Unable to communicate with inverter. The unit controller will disable compressor operation. Replace communication cable between inverter and CORE Unit Controller. If alarm continues, replace CORE Unit Controller or inverter.

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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