Carrier gas furnace problem
#1
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Carrier gas furnace problem
My furnace kicks on, sometimes it will fire and occasionally it won't. It just runs (inducer), without lighting. I run the self-test feature and all 4 stages (inducer, igniter, hi-speed fan, and low-speed fan)work correctly. Any advice on what to check next?
#3
The inducer motor running means that the thermostat is calling for heat.
The next step in the ignition sequence is for the pressure switch to close when the inducer motor comes up to speed, which in turn turns on the hot surface ignitor.
So the probability is that the pressure switch isn't closing --- you need to check and verify that.
If it's not closing, it's VERY unlikely that the pressure switch is the problem. The pressure switch is just revealing a defect in the furnace combustion and venting system.
Check to be sure that the pressure switch tubing has no holes or cracks. Use a paper clip or small drill bit to clean out the fitting the pressure switch tubing connects to on the inducer motor housing, which can get plugged with rust or crud. Be SURE you get all the way through the fitting into the inducer motor housing!
The next step in the ignition sequence is for the pressure switch to close when the inducer motor comes up to speed, which in turn turns on the hot surface ignitor.
So the probability is that the pressure switch isn't closing --- you need to check and verify that.
If it's not closing, it's VERY unlikely that the pressure switch is the problem. The pressure switch is just revealing a defect in the furnace combustion and venting system.
Check to be sure that the pressure switch tubing has no holes or cracks. Use a paper clip or small drill bit to clean out the fitting the pressure switch tubing connects to on the inducer motor housing, which can get plugged with rust or crud. Be SURE you get all the way through the fitting into the inducer motor housing!