Furnace help?

**dk_alaskan** · 11-29-2006, 07:36 PM

Right now, i have no heat in the house and it is in the single digits. I think i have narrowed the problem down to no gas getting to the burners. The gas is on, the system is an auto pilot system. It is an RPJ II Aeroair furnace. Anybody have a clue or do i need to call in the furnace repairman?

**SkiEvil** · 11-29-2006, 08:12 PM

Depending on the age of the furnace there is a light, it is usually in the bottom portion of the furnace that will blink an "error" code. There is then somewhere on the furnace a key for the codes. This will point you in the right direction.

Do you hear the blower kick on for a while and then the burners do not fire? I had that happen and it turns out that I had a hornets nest in the vent pipe. It tripped the pressure switch that would not let the gas flow. Purged the pipe and all is well.

**bio-smear** · 11-29-2006, 08:16 PM

Auto pilot, as in you don't need to light it?
most older furnaces have a capilary tube that runs gas to the pilot...you have to hold the pilot switch on until that heats up, otherwise it wont stay on. Maybe yours is all new school and doesn't have that problem.

Edit: Had a similar problem to SkiEvil once too.

**dk_alaskan** · 11-29-2006, 08:26 PM

SE, there is a light in there, but no lights are on from what i can tell. how high up was the hornets nest? So it may be a pressure issue (the blower is working, it blows cold air) since i have air blowing but no gas?

**SkiEvil** · 11-29-2006, 08:29 PM

The light only flashes right when the blower kicks on. I got lucky, my nest was right on the outside where the bend in the pipe is. It did go back in about a foot though. I soaked it good with wasp killer before I started digging it out.

**train07** · 11-29-2006, 08:43 PM

no, I'm really bored

**Pow4Brains** · 11-29-2006, 09:33 PM

check the "high limit" above the heat exchanger (should be a little redish button). if it trips, the blower will just keep running. is it surface ignition or does it have a pilot light? do you have a volt meter and know how to use it? if so, make sure you are getting 24v to the red (usually) wire on the gas valve (most likely labeled W1)

**MOHSHSIHd** · 11-29-2006, 10:16 PM

well, our furnace is fucked up too....it also has an auto-ignition system as well and blows cold air all the time.....gotta cut all power, turn off the thermostat, turn off the gas for 5 minutes, turn gas back on, turn power back on, put thermostat back to desired temp...

that usually resets it and fixes the problem....

**dk_alaskan** · 11-30-2006, 01:00 AM

Originally Posted by Pow4Brains

check the "high limit" above the heat exchanger (should be a little redish button). if it trips, the blower will just keep running. is it surface ignition or does it have a pilot light? do you have a volt meter and know how to use it? if so, make sure you are getting 24v to the red (usually) wire on the gas valve (most likely labeled W1)

i don't know the part by name, but i will know by sight, what does the heat exchanger look like and how do i fix the trip switch if in fact it has been tripped?

**INDY GS** · 11-30-2006, 10:46 AM

If the furnace is running, but not heating, and is an auto pilot system, it is most likely your electronic ignitor that has gone bad. either that or a bad thermocoupler.

Both are easy to fix and pretty cheap.

An ignitor will set you back between 20 & 40 bucks. a thermocoupler is specific by model, but I believe lowes has them in a universal for around 5 bucks.

I'd change out the ignitor first.

It mounts with one screw and has a wiring harness. very easy to switch out.

**dk_alaskan** · 11-30-2006, 12:54 PM

will the ^2 parts affect gas flow? it seems like there is no gas flow and if there is no gas flow, would replacing the ingnitor fix the problem?

**INDY GS** · 11-30-2006, 01:17 PM

Yes, there is an automatic shutoff if the ignitor isn't working. I had this problem a few years ago. I paid out the ass to have it fixed at 3AM on the coldest day of the year. I wanted to wait and call in the AM, but the wife insisted since our sone was still a baby.

I almost guarantee this is your problem. You will fix it for less than $50

**dk_alaskan** · 11-30-2006, 03:37 PM

pulled the ignitor, looks like it is cracked. going to try and replace that. Thanks for the help indy. BTW, got the package today, thanks a lot for the h and h (help and hookup)