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ed3120
Furnace works, but blower stopped

I have a Heil Model #NTC6100KFG1 furnace.

Yesterday, I noticed that the house was cooler than usual, and the blower is not turning on. The furnace itself still has power and turns on (it still gets hot), but the blower does not. The whole house humidifier attached to the furnace still has power and works properly. My thermostat is still set to “Heat” and the fan setting is still set to “Auto”, as it always is. Temporarily setting the fan switch to “On” did not change anything.

How do I go about troubleshooting this? I assume I need to check the blower itself to ensure that it can spin. Are there other sensors or wires that I should be checking for voltage or continuity?

Thanks for any help,
Ed

dj1
Re: Furnace works, but blower stopped

If you have a circuit board light (small LED, green or red), you can troubleshoot the problem by the number of blinks it makes. To de-code call Heil customer service.

Otherwise: If there is power to the blower motor, most likely it's the blower motor, the motor capacitor or cover panel switch.
I'd start with replacing the motor.

JLMCDANIEL
Re: Furnace works, but blower stopped

If the blower doesn't run in the auto or the on position then it is either the blower motor or the motor relay on the control board. It could be as simple as something stuck in the blower fan.

Jack

ed3120
Re: Furnace works, but blower stopped

The blower runs when I plug it into AC. I checked for AC voltage on the circuit board where the blower is plugged in. I get nothing. I'm guessing the board need to be replaced.

JLMCDANIEL
Re: Furnace works, but blower stopped

Make sure the 120volt feed is making it to the board, it could just be a bad connection of loose wire.

Jack

ed3120
Re: Furnace works, but blower stopped
JLMCDANIEL wrote:

Make sure the 120volt feed is making it to the board, it could just be a bad connection of loose wire.

Jack

Since the furnace turns on (after pressing the interlock button), I think I can assume that the 120v is hitting the board. If I unplug the power line from the interlock, then the entire system is dead and even the furnace itself won't turn on.

JLMCDANIEL
Re: Furnace works, but blower stopped

The board uses 24 volts primarily, you just need the 120 for the fan.

Jack

ed3120
Re: Furnace works, but blower stopped
JLMCDANIEL wrote:

The board uses 24 volts primarily, you just need the 120 for the fan.

Jack

If I check for voltage where the wire from the door switch connects to the board, and one of the neutrals on the board, I get 120v.

dj1
Re: Furnace works, but blower stopped

By your latest reports, you could have a defective control board.

before you rush to buy a new board, do some math: a new board is $150 or more and non-returnable. If it's not the board, and you continue to buy other parts, you may be throwing more good money away. You can easily spend enough money to buy a new furnace.

How old is this furnace?

ed3120
Re: Furnace works, but blower stopped

I replaced the control board and everything works perfectly now.

Thanks.

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