Lennox Unit controller

Lennox Error Code 137

Unit controller

What It Means

  • DAMPER STUCK CLOSED

Causes & actions from Lennox

How it shows
  • M4 alarm code: 137

• The damper is not opening to the target percentage. Unit may be bringing in less than anticipated outdoor air. • Inspect damper and / or actuator for blockage. alarm is raised when damper actuator feedback exceeds 2v under target for 2 minutes. • Alarm will reset automatically when damper feedback falls to 1.8v within the target voltage.

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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