What It Means
- Prove switch open. OR:Blocked inlet/exhaust vent; OR: Prove switch closed prior to activation of combustion air inducer.
Lennox Ducted Heating
Lennox Error Code OFF, SLOW FLASH
Ducted Heating:
Causes & actions from Lennox
How it shows
- SureLight board LEDs (DS1/DS2): OFF, SLOW FLASH (led1: off, led2: flashing (slow))
- SureLight board LEDs (DS1/DS2): OFF, SLOW FLASH (led1: off, led2: flashing (slow))
- SureLight board LEDs (DS1/DS2): OFF, SLOW FLASH (led1: off, led2: flashing (slow))
This manual entry does not list further causes or actions.
Applicable models & manual sources
- G43UF
Prove switch open. OR:Blocked inlet/exhaust vent; OR: Prove switch closed prior to activation of combustion air inducer.
- G43UF
Prove switch open. OR:Blocked inlet/exhaust vent; OR: Prove switch closed prior to activation of combustion air inducer.
- G43UF
Prove switch open. OR:Blocked inlet/exhaust vent; OR: Prove switch closed prior to activation of combustion air inducer.
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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