Goodman furnace issues

nismogsxr

I have a Goodman furnace, model GPG1342090M41BA, and when I turn on the heat, the inductor fan and propane valve do not turn on. Half a minute goes by and the blower motor will come on and circulates cold air in the house. Doing a little troubleshooting I thought it was the board and replaced it, but the furnace still isn’t working. Reason I thought that was board isn’t sending 120V to inductor fan.  Transformer is putting out what it is supposed to and inductor fan is not locked up. I bypassed the thermostat inside the house to see if that was the problem and the inductor fan and propane valve turns on, and tries to ignite. The second the propane ignites, it blows the fuse on my board. Went out to my furnace and bypassed the thermostat there to rule out shorted wiring in the house, and it does the same thing. Where should I start troubleshooting in the furnace? Shorted wire in furnace, bad igniter, bad flame sensor, etc? Thanks for any help, been without heat for 2 days now

EdTheHeaterMan

When was the last time it operated properly?
https://www.theacoutlet.com/documents/Owners-Manual-Goodman-GPG13.pdf This is the manual. Service starts on page 33. 

EdTheHeaterMan

Look at the wiring that is connected to the new control board. See if there are any wires that are burnt or have melted insulation. Look where the wires may get close to the flame

EdTheHeaterMan

I was looking at the sequence of operation on page 24. it appears that at about the time you describe the control board blows a fuse, there is a change from the high to the low flame operation. This is an indication that the low speed fan may be blowing the fuse. Look at the wires to the Induced draft blower (the small fan near the exhaust outlet) to see if there is any damage to that wiring

nismogsxr

I noticed It not working when I woke up in the middle of the night Sunday when my ecobee thermostat told me that the furnace had ran for 3 hours straight and the house temp had dropped 3 degrees. When I get home in the am, I will check the wires coming out of the inductor fan, and all of the wires that are around that area. I know there is a metal hole like 1” in diameter that the wires for the inductor fan, flame sensor, igniter, limit switch, and gas valve go through that is bare metal.

EdTheHeaterMan

nismogsxr said:

I noticed It not working when I woke up in the middle of the night Sunday when my ecobee thermostat told me that the furnace had ran for 3 hours straight and the house temp had dropped 3 degrees. When I get home in the am, I will check the wires coming out of the inductor fan, and all of the wires that are around that area. I know there is a metal hole like 1” in diameter that the wires for the inductor fan, flame sensor, igniter, limit switch, and gas valve go through that is bare metal.

That should have a wire connector clamp or a grommet so the wires can't rub and chafe the insulation away.
Poor workmanship, especially if that is the cause of the problem.

nismogsxr

Didn’t see anything wrong with any of the wires. Looking at where I thought was wires going through a ole that was bare metal, there was a grommet there. It had fallen out, so I put it back in place. Testing for a short I noticed that of the two wires for the furnace limit switch, one side has continuity to ground. That wire goes to the propane valve, which then goes to the contactor. From that terminal on the contactor, it goes to the transformer where it’s on a terminal that goes to a ground. So I guess that is ok for having continuity to ground lol.  But when looking at my contactor I also noticed some black and melting. I have continuity on both poles of the switch without pushing the contactor in. I am just wondering if that contactor is my whole problem. I know it needs to be replaced, but praying that’s my issue

mattmia2

Is there a gap between the poles of the contactor? It looks like it is welded together but it is hard to tell from that angle.

mattmia2

EdTheHeaterMan said:

nismogsxr said:

I noticed It not working when I woke up in the middle of the night Sunday when my ecobee thermostat told me that the furnace had ran for 3 hours straight and the house temp had dropped 3 degrees. When I get home in the am, I will check the wires coming out of the inductor fan, and all of the wires that are around that area. I know there is a metal hole like 1” in diameter that the wires for the inductor fan, flame sensor, igniter, limit switch, and gas valve go through that is bare metal.

That should have a wire connector clamp or a grommet so the wires can't rub and chafe the insulation away.
Poor workmanship, especially if that is the cause of the problem.

Sometimes I have seen in really cheap appliances where they just hem the edge of the metal and hope it doesn't cut through the wiring.

EdTheHeaterMan

mattmia2 said:

That should have a wire connector clamp or a grommet so the wires can't rub and chafe the insulation away.
Poor workmanship, especially if that is the cause of the problem.

Sometimes I have seen in really cheap appliances where they just hem the edge of the metal and hope it doesn't cut through the wiring.

OP found the grommet and put it back. I have seen that also Matt


@nismogsxr
The picture shows a 220V contactor that should be replaced. That operates the compressor. It has nothing to do with the heating system or the low voltage fuse on the PC board. You need to find where the overload or short circuit is in the 24 Volt Control circuit. That fuse is there if more than 3 amps (or 5 amps) goes thru the 24V control system. That is usually caused by a thermostat wire. (I'm guessing the green one but can't be sure. I'm not MacGyver trying to disarm a bomb here.)

nismogsxr

mattmia2 said:

Is there a gap between the poles of the contactor? It looks like it is welded together but it is hard to tell from that angle.

There is a gap there, but there is continuity on both sides of the switch without pushing contactor in

EdTheHeaterMan

nismogsxr said:

mattmia2 said:

Is there a gap between the poles of the contactor? It looks like it is welded together but it is hard to tell from that angle.

There is a gap there, but there is continuity on both sides of the switch without pushing contactor in

That continuity may be from the wires going thru the compressor and the other electrical devices on the system. To truly check continuity, you must remove the wires.

With the electricity turned on, see if there is a difference of voltage between the black wire connection and the white wire connection, with the wires connected. If there is voltage, then the contactor is open and not the cause of the low voltage fuse failure.