Goodman GMS80453ana INOP

diynoobee · 07-27-2010, 02:19 PM

Hello all,

First let me say that I am new to this forum and not to knowledgeable about HVAC systems. Anyhow I need some assistance on getting my unit up and running. I was having trouble with the controller board continually blowing the 3A fuse. A friend that said he knows about HVAC put in a 5A fuse, when this happened the unit will not even blow the fuse. I have replaced the controller board with out any luck. Looking at the diagram on the door panel I think it could also the step down transformer to the controller board. Well if anyone has any suggest, it would be most welcomed.

Thanks,
The Noob

**beenthere** · 07-27-2010, 06:04 PM

Probably burnt out the transformer when he used that larger fuse.

Use a meter, and look for a short in the low voltage wiring.

diynoobee · 07-28-2010, 02:20 PM

Quote:

Originally Posted by beenthere

Probably burnt out the transformer when he used that larger fuse.

Use a meter, and look for a short in the low voltage wiring.

beenthere I just found that it was indeed the xformer. I at least now can turn the fan on. But when I try to turn no the AC the fuse pops open. Any ideas why.

Thanks!

P.S. Even the fan on the temp dropped 2deg.

**beenthere** · 07-28-2010, 04:58 PM

There is a short in the low voltage circuit of the outdoor unit.
Either in the wiring from the furnace board to the unit. Or in the circuit in the outdoor unit.

diynoobee · 07-28-2010, 05:28 PM

Quote:

Originally Posted by beenthere

There is a short in the low voltage circuit of the outdoor unit.
Either in the wiring from the furnace board to the unit. Or in the circuit in the outdoor unit.

With that said, how do I a troubleshoot the low voltage circuit of the outdoor unit?

Thanks!!!!

**beenthere** · 07-28-2010, 05:37 PM

If you have a meter. Check for continuity to ground, in the wires.
if not. Remove the low voltage wires for the outdoor unit(writing down and or marking where they were connected). Turn power back on, and set stat for cooling. If the fuse pops, you have a short in the wire. if it doesn't then the short is in the unit.

Yoyizit · 07-28-2010, 06:52 PM

This will pay for itself pretty quickly
http://www.parts-express.com/pe/show...number=074-022

diynoobee · 07-28-2010, 06:53 PM

Quote:

Originally Posted by beenthere

If you have a meter. Check for continuity to ground, in the wires.
if not. Remove the low voltage wires for the outdoor unit(writing down and or marking where they were connected). Turn power back on, and set stat for cooling. If the fuse pops, you have a short in the wire. if it doesn't then the short is in the unit.

Beenthere,

Ok used the meter to ground and there was no short to ground on either of the 2 wires that go from the control board to the outside unit. But the fuse doesn't pop with the 2 wires disconnected from the control board. I did however do a continuity check of the 2 wires together and it did buzz. Should there be continuity between these 2 wires.

The 2 wires are connected on the furnace control board from the outside unit are White which is connected the "C" and Red which is connected to the "Y" which shares the yellow wire from the thermostat.

Appreciate your continued support!!!!!!

diynoobee · 07-28-2010, 06:58 PM

Quote:

Originally Posted by Yoyizit

This will pay for itself pretty quickly
http://www.parts-express.com/pe/show...number=074-022

You got that right!!!! been through 6 fuse during the trouble shooting process!!

**beenthere** · 07-28-2010, 07:48 PM

If the wires are disconnected on both ends. Then there should be no continuity.

If they were still connected to the outside unit. Then there should be continuity.

diynoobee · 07-28-2010, 08:52 PM

Quote:

Originally Posted by beenthere

If the wires are disconnected on both ends. Then there should be no continuity.

If they were still connected to the outside unit. Then there should be continuity.

Ok.. From outside the were connected. Not sure if I am reading the drwgs correctly but it looks like the Y and C are in series with a LPS, HPS and a coil. Y to HPS to LPS to Coil to C. You suspect that this circuit has an issue. I took the Y and C of the control board and did a continuity check to the HVAC unit (assuming that its grounded) but neither Y or C was grounded.

www.goodmanmfg.com/Portals/0/pdf/SS/SS-SSX14.pdf

Yoyizit · 07-28-2010, 10:21 PM

Quote:

Originally Posted by diynoobee

the controller board continually blowing the 3A fuse.
put in a 5A fuse, when this happened the unit will not even blow the fuse.

24 V/(>3 A) = <8 ohms
24 V/(<5 A) = >5 ohms

Normal is probably
24 V/(<1.7 A) = >14 ohms.

If your circuit fault impedance is between 5 and 8 ohms instead of more than 14 ohms or less than 5 ohms, you may need more than a continuity checker to find the problem.
The solid state components on the control board need at least 1 Vdc to begin turning on.

Can you post a link to your tester?

diynoobee · 07-28-2010, 10:32 PM

Quote:

Originally Posted by Yoyizit

24 V/(>3 A) = <8 ohms
24 V/(<5 A) = >5 ohms

Normal is probably
24 V/(<1.7 A) = >14 ohms.

If your circuit fault impedance is between 5 and 8 ohms instead of more than 14 ohms or less than 5 ohms, you may need more than a continuity checker to find the problem.
The solid state components on the control board need at least 1 Vdc to begin turning on.

Can you post a link to your tester?

It's like beenthere said, if the fuse doesn't blow when the compressor is not connected its something from the compressor up to the control board.
http://us.fluke.com/fluke/usen/Digit....htm?PID=56135

**beenthere** · 07-28-2010, 10:38 PM

The coil of the contactor could be shorting to itself. And not have enough resistance.

diynoobee · 07-28-2010, 10:53 PM

Quote:

Originally Posted by beenthere

The coil of the contactor could be shorting to itself. And not have enough resistance.

What is a good resistance... 8ohms?