Please Help Diagnose my Gas Furnace!

[sweetpeakaris]

First off January is always a bad month for us financially. My husband got 3 weeks off in December, and had to claim unemployment for that time, so we are playing catch up in January.

My Dishwasher and over the stove microwave already went out a couple weeks ago, no biggie as I can live without those until we repair or replace.

Now, something is wrong with my Gas forced air Furnace. I have it set between 68 & 70 on auto, it's suppose to cut on and off to keep the house warm. The last few days I notice the house getting cold and the thermostat reads the inside temp as 60 degrees, but the furnace does not kick on, it should kick on when the inside temp starts to drop. If I turn the thermostat off and back on, the furnace will kick on and work fine, house gets warm for maybe 12-24hours then I have to repeat the process. Also, it seems to be cutting off and on more than normal IMO, like every 6 mins or so?.

Does anyone know why this is happening? I really can't afford to call a tech and would like to troubleshoot it myself first if that's even an option.

 

[disney212]

We had a similar problem with ours about 5 years ago. Turns our we had a bad "relay" switch. The folks at home depot got us a new one and DH installed it himself in less than 10 minutes. Hope that helps! The folks at Home Depot were awesome and explaining how to do it.

 

[lvillotta1]

Sounds similar to what mine was doing. My problem was the ignitor in the furnace was not catching the flame. My repair guy spent 2 days trying to get al the parts as the furnace was 22 years old. He tried everything he could. In the end i have a brand new furnace. Since I am staying in my house forever I had no choice. It cost me $2800. My air conditioner still is working so hopefully I can get many more years out of it.

 

[daughtersrus]

It could also be the thermal coupler. DH had to replace ours every few years.

 

[wgeo]

I know very little about furnaces, other then our own experiences.

Once our furnace wouldn't kick on even when the thermostat said the house was lower then we had it set for. Turns out our thermostat just needed fresh batteries - not kidding - paid for a house call for that . If I turned the thermostat off and on it would kick the furnace on but apparently there wasn't enough juice in the batteries to run things properly.

Another time the furnace would try to turn on but the flame wouldnt catch. The furnace kept trying to kick on but when the flame didn't catch it would turn off, reset itself and try again later. Turns out there is a small flint-like thing (how's that for official terminology?) that has to spark to start the fire and it can get dirty. It's hard to reach, but once we got it cleaned free of dust, it sparked fine and everything had been great since.

Good luck!

 

[Zerosinthecloset]

Do you change out your filters regularly? Had a house once where the furnace would not come on. Resetting the breaker would get it to work for a while, but somehow the unit detected a lack of air flow, so it would shut off. The filter was pretty clogged, and replacing it solved the problem.

 

[3boymthr]

DH is in HVAC. There are a couple of cheap/free things that you can check before you call in a professional. As PP mentioned he tells me all the time that many people have problems with their heat and it turns out to be a simple problem like batteries for the thermostat or an other wise busted thermostat. Since replacing the batteries will only cost you $5 (or less!) I'd try that first. Also make sure that the thermostat is clean. DH is constantly taking the cover off of ours and cleaning it off, sucking all the dust out of it (we do have a cat which contributes to the dust). If that doesn't work and you or your hubby are handy try replacing the thermostat (which will cost you only about $40 for a cheap one).

On another take, DH commented to me one time that they had this house with a horrible problem with the furnace cutting out - they'd gone there multiple times tried everything they could think of and could find nothing wrong but the problem kept happening. Finally they went there one day and noticed that the flame was getting dimmer and dimmer - it was oxygen starved - Turns out the house had recently been evaluated by the electric company and they owners had had it sealed to cut drafts and make it more energy efficient and as a result there was not adequate fresh air getting to the furnace. So I'd also make sure that there is nothing blocking off your furnace and that it is getting adequate air flow (if it's in a closet leave the door open).

 

[scrapquitler]

The last time we had a problem with our gas fireplace it turned out that the thermostat (the control thing where you set the temperature in our upstairs hallway) was the problem, not the furnace itself. It was an inexpensive and easy fix.

 

[POOHsie]

I had that problem this year on-and-off in Oct-Nov. Serviceman came time and again, but luckily it was new and covered under warranty. What he did that finally worked was install a piece of 90-degree angled pipe because it was always a pressure problem. The angled pipe somehow altered the airflow and now my furnace works fine. Good luck to you!