Lennox Unit controller

Lennox Error Code 176

Unit controller

What It Means

  • SBUS OBSOLETE M2 COMMAND

Causes & actions from Lennox

How it shows
  • M4 alarm code: 176

This alarm occurs when a S-BUS primary device sends a M2 style command to the CORE Unit Controller. The alarm is immediately cleared and a history of the event is stored.

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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