Lennox Unit controller

Lennox Error Code 9 - 11

Unit controller

What It Means

  • RESERVED

Causes & actions from Lennox

How it shows
  • M4 alarm code: 9 - 11

This manual entry does not list further causes or actions.

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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