What It Means
- ID ADD ON BOARD PROBLEM
Lennox Unit controller
Lennox Unit controller Error Code 79
Unit controller
Causes & actions from Lennox
How it shows
- M4 alarm code: 79
Add-on board problem, reset CORE Unit Controller to clear. When the communication alarm 80 persists for more than 30 seconds even after several retries for establishing the communication this Alarm is logged. Alarm can only be cleared by CORE Unit Controller reset.
Applicable models & manual sources
- MODEL L - M4 UNIT CONTROLLER
ID ADD ON BOARD PROBLEM
MODEL L - M4 UNIT CONTROLLER, M4 Unit Controller
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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