Goodman Furnace - Inducer Motor Doesn't Start, 3 Blinks

I woke up this morning to no heat. Furnace is model #capf3030b6ba installed in the 2011-2012 timeframe.

I get 3 blinks from the circuit board - pressure switch stuck open. When it calls for heat, the inducer motor doesn't run. I bench tested the pressure switch with a multimeter by sucking on it and it works. I rigged a 120V power cord up to the inducer motor - it works too. I checked voltage from the circuit board when it calls for heat and briefly get 2.4 volts AC and then nothing.

So what am I looking at here? Circuit board?

Thanks!

 

That seems to be an air handler model no., not a furnace.

Sounds like the control board though, since inducer runs when powered directly. Check all the connections to the board to make sure they are clean and secure, and verify you have 120 volts reaching the board using your meter. A little light tapping on the relays is always worth a shot.

 

Yes you're right - that's the P/N for the air handler. That explains why I couldn't find a control board for it

I snapped a pic of the control board and then googled the P/N of that and found a replacement for $45 on Amazon with free one-day shipping. Seems to be a reasonable deal.

I'm going to try tapping on the relays just for fun. Thankfully we're on a warming trend here in the Northeast and last night was the last night for a while that I'll need heat.

 

The inducer must start first. So if it isn't running... don't bother checking the pressure switch.

On a call for heat I check the two wires to the inducer motor for 120vac.
If it's there.... the motor is bad. If it's not there.... it's in the connecting plug or the board.

 

I figured that. There would be no pressure for the pressure switch to work with unless the inducer was running. It's an HE furnace so it has PVC intake and exhaust that runs outside. I was afraid I was going to find a ground up critter in the inducer but it spins fine. Like I said, I rigged up an old lamp cord and plugged it in and it works fine. 2.4V briefly from the circuit board - it almost has to be the culprit.

It's not a huge repair, but what happened to major appliances that lasted decades without issue? This is a newer furnace by most standards - it's a bit annoying to have it fail already. Engineered obsolescence I guess.

 

The board quality is mediocre.
The relay quality and how they're soldered in is the biggest issue.

 

The new control board fixed it. Thanks all!

 

Good job. Thanks for letting us know how you made out.