comfortmaker model#GNJ075N12A1

camcdole

Hello all, I may have an older version of what seams to be a problem riddled furnace. It will not produce heat! The A/C portion of it works but not the heat. It will "kick on" and act like it is going to heat at the right tempeture on the thermostat but no heat. Help anyone. Mother-in-law says she will "kill" me if the heat doens't work when she visits! :-) Please help.

#CARRIERMAN

Hi camcdole

Can you give me some specifics about what it is doing. Do you hear a motor come on or any thing when you turn the thermostat to heat? If you can give me a little more to work with, we'll get you out of hot water.

Good luck
Rusty

#CARRIERMAN

Hi again camcdole

I just read your other response, sounds like you have a bad ignitor. This will be a porcelin piece with a M shaped piece on top of it. Look in the middle of the M piece and I'll bet you see the fracture. The generic replacement for the ignitor is a Robertshaw part# 41-414.

Good luck
Rusty

camcdole

THANKS for the reply. I thought it might be the ignitor after your replies, but now I think it's not. Reason being is I went through the motions of turning off the power and all again and this time I saw the glow of what I am guessing was the ignitor. It lit once and no flame and then again a few seconds later. WHAT NOW?

Does any one know where to get comfortmaker manuals from?

#CARRIERMAN

Hi camcdole

If you have a voltmeter, set it to 24 volts. Put one probe on each of the gas valve wires, it does not matter which probe is on which wire. Run the furnace again, when the ignitor glows see if you are showing 24 volts on your meter. It sound like this furnace either has a Honeywell gas valve or it has an ignition control problem. If you are showing 24 volts at your meter, you will need to replace gas valve. If you replace the gas valve my reccomendation is a Robertshaw 720-079. Let me know if you need more help.

Rusty

mdshunk

I'm predicting a class action Smart Valve lawsuit. You?

#CARRIERMAN

Hi camcdole

Mdshunk just hit on something that had not even crossed my mind. Your furnace could have a smart valve system on it, for your sake God I hope not. These gas valves were the biggest joke that ever came out of a engineers mind. These things are extremly expensive and the most ureliable piece of **** that I have ever seen. If you have a smart valve setup, all you can do is change out the gas valve assembly. You have no other choice.

Good Luck
Rusty

averyds

I need the parts list for my furnace, a RPJ 2 about 10 years old. Can anyone tell me if the gas valve has a control board in it? The problem is when the igniter lights up,you have to shake the electric plug that conects to the gas valve.I'm not sure if the short is inside the plug or the gas valve? Maybe I need a wiring diagram?

acefurnacefixer

All you have to do is sand the flame sensor (its on the oppisite side of the burner rack from the ignitor) with some 200 grit sand paper or emry cloth and the furnace should start making regular heat again. also listen for the "click" of the gas valve opening and a slight "hiss" that will be the gas rushing out for 4 seconds. If the flames do not ignite when the ignitor is glowing then you have either very dirty burners, or a bad gas control valve. Your furnace DOES NOT have a smart valve.

#CARRIERMAN

Hi averyds

To answer your question, if the gas valve says Honeywell smart valve or smart valve 2. It has the ignition and flame proving conrols built in. If what acefurnacefixer suggested does not work you will have to replace the gas valve assembly. They are a pretty expensive valve, so if it comes to that be ready.

Good luck
Rusty