What It Means
- Pressure switch open or has opened 5 times during a single call for heat; OR: Blocked inlet/exhaust vent; OR: Condensate line blocked; OR: Pressure switch closed prior to activation of combustion air blower.
Lennox Ducted Heating
Lennox Error Code LED #1: OFF, LED #2: SLOW FLASH
Ducted Heating:
Causes & actions from Lennox
How it shows
- SureLight board LEDs (DS1/DS2): LED #1: OFF, LED #2: SLOW FLASH (led1: off, led2: flashing (slow))
This manual entry does not list further causes or actions.
Applicable models & manual sources
- G24M
Pressure switch open or has opened 5 times during a single call for heat; OR: Blocked inlet/exhaust vent; OR: Condensate line blocked; OR: Pressure switch closed prior to activation of combustion air blower.
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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Continue in ACLogics with guided diagnosis for your equipment and symptoms.
