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The light is flashing 3 times inside the furnace (my heat is…

Customer Question
The light is flashing...

The light is flashing 3 times inside the furnace (my heat is not working)

Contractor's Assistant: Did you double-check the thermostat's settings? And what about the filters?

Yes, and yes

Contractor's Assistant: Do you plan on doing the work yourself?

Heat is coming out cold out of the vents

Contractor's Assistant: Anything else we should know to help you best?

Not really. I took the face off of the furnace and the light is flashing 3 times. I turned the furnace off to reset it The light is still flashing 3 times. Also, it was making a funky noise last week. Like, really noisy when the heat turned on.

Submitted: 4 months ago.Category: HVAC
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Answered in 3 hours by:
3/10/2018
HVAC Technician: gotoman for ac, HVAC Technician replied 4 months ago
gotoman for ac
gotoman for ac, HVAC Technician
Category: HVAC
Satisfied Customers: 5,348
Experience: 51 years of experience install design and repair of all makes and models of AC
Verified

Russ here. If you could tell me make and model number of furnace please. Russ

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Customer reply replied 4 months ago
Model # N9MP105OB12B1
Serial # AO41991859
HVAC Technician: gotoman for ac, HVAC Technician replied 4 months ago

3 flashes is pressure switch open. This can be caused by a bad induce draft motor. The small motor in middle of furnace. This may be the noise you are hearing. Turn power off to furnace and retry and see if the small fan comes on. Feel it and see if it is warm. Let me know. Russ

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Customer reply replied 4 months ago
That’s exactly what the back of the furnace cover said. I no longer hear the noise. The fan is functional and working.
HVAC Technician: gotoman for ac, HVAC Technician replied 4 months ago

This could be several problems. Faulty switch,blocked vent or clocked tubing. Check the vent for ice first. If it is clear check the hoses on the pressure switches. These are small switches that have hoses connected to inducer draft fan assembly. Remove hoses and clean small connecters with paper clip. Let me know. Russ

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HVAC Technician: gotoman for ac, HVAC Technician replied 4 months ago

Do you still need help. Russ

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