Lennox Zone controller

Lennox Error Code 0101

Zone controller

What It Means

  • Insufficient heating

Causes & actions from Lennox

How it shows
  • harmony diagnostic led1234: 0101 (led1: off, led2: on, led3: off, led4: on)

Occurs when there is a call for heating and the Discharge Air Sensor does not sense a increase in supply air temperature indicating the heating is not functioning properly.

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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