Coleman Furnace Error Code 3 FLASH
Combustion air pressure switch failed to close; the normally open pressure switch contact did not close at the beginning of the heat cycle, possibly caused by faulty inducer, blocked vent pipe, broken pressure switch hose or faulty pressure switch.
SourceColeman Gas Furnace - Service Manual: DGAA077BDTBFurnace Control Diagnostics section
The full 3 FLASH procedure
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SourceColeman Gas Furnace - Service Manual: DGAA077BDTBFurnace Control Diagnostics section
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Where this code is documented
1 manual in the MyPros+ library documents this code for Coleman furnace.
Models covered by the manuals that document this code
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