Lennox Equipment not specified

Lennox Error Code 409

Equipment not specified:

What It Means

  • OD Control Board Low 24VAC

Causes & actions from Lennox

How it shows
  • iComfort S30 alert: 409

Priority condition: Service Soon The secondary voltage for the applicable system component has fallen below 18VAC. This may be due to: • Secondary voltage is below 18VAC. • If this continues for 10 minutes, the thermostat will turn off the applicable system component.

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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