Lennox Unit controller

Lennox Error Code 165

Unit controller

What It Means

  • ECONOMIZER UNCONFIGURED

Causes & actions from Lennox

How it shows
  • M4 alarm code: 165

Configuration ID 1, position 2 is set to U. Select applicable option using setup/install wizard.

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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