Hi,

I have a Goodman, Dependable 92, Gmpn100-4. THe fan works, but the heat doesn't. There are no indicator lights that flash(red). The ignitor glows for about 3 seconds and then shuts off w/o lighting the furnace. Any help would be appreciated.

If the ignitor is glowing then either there is no gas or the gas valve is not getting power to it. Do you here a click when the ignitor is glowing try to open the gas valve??

There is not a click

Does this unit vent with metal or plastic pipe?

Metal

At this piont is sounds like a control board probem or may be a pressure switch probem not staying in.


http://americanhvacparts.com/Merchant2/graphics/00000001/PRS1005576AB.jpg it may also be a black switch.

Here is a complete factory service manual. It covers more than one unit so be sure to relate the instructions to the unit you have installed in your home. Your model GMPNXXX is listed.

http://www.hvacpartsshop.com/Gmph075-4%20Series.Pdf

The gas in the house is working. However the gas is not making its way to the ignitor. I do not hear a click or smell the gas when the fan kickson and the ignitor glows. Does this lend itself to the pressure switch or control board, or is there another problem? If so, what can I do to troubleshoot it?

If the ignitor is glowing then the pressure switch is working, at least for the 3 seconds you are saying the ignitor is glowing.. do you have a electric meter? If so you can chck for power at the gas valve 24 volts. The gas valve switch is on correct??

Gas valve is reading at 24 volts and the gas switch is on. I am guessing this means I need a new control board?

If you are getting 24 volts to the gas valve but not getting a click to let the gas threw them most likely you need a gas valve. When the ignitor is glowing try tapping the valve with a screw driver or plyers it may just be stuck.

I have same problem Goodman GMPN100-4, replaced draft inducer, Ignitor, and Control Board.

Gets to ignitor red hot and draft motor running, but my gas valve is reading at 69 to 70v AC. It reads this value whether it's cycling or not. What voltage is that gas valve supposed to read?

I hear no click, smell no gas, hear no hiss, after 15 or 20 secs, it cycles to try again. Can anyoine tell he how to test that gas valve by voltage and what is normal way to see if that's my problem?

I mean, if gas doesn't flow, nothing lights, and flame sensor causes the thing to cycle.. correct. It sure seems like I need a gas valve. Damn thing worked fine all last winter. It's a 1993 and seems like many, many parts are failing. So, I am rebuilding it pretty much replacing all the common failing parts and cleaning it all up inside & out. Might as well now that I had to go this far. PLEASE ADVISE.

GMPN100-4 Control Board comes with a light on the board. Comes with a chart.

LED ON = No Fault
OFF = Gas Valve Fault Detected

1 flash = ignition failure (after 3 tries and start of soft lockout)
2 flash = Pressure Switch Stuck Closed
3 flash = Pressure Switch Failed to Close
4 flash = Limit Switch Failed Open
5 flash = Flame Present With Gas Valve Output Off
6 flash = Brownout Voltage
7 flash = Fault Twinning
Rapid Flashing = Wrong Polarity of 120 VAC and Neutral

HTH, looks like your answer is top of list, gas valve fault...

My Light is stay on 100% stating noa failure, but I still can't get a flame?