Getting Cold In Here

[fuzzy57]

My furnace is not responding to the thermostat. The pilot light is on, the breaker is on, the power switch is on. Have I missed something simple to check before calling a service tech ?

[Tom Kendrick]

Most HVAC units have a safety switch that does not allow the unit to run if the access panels are open. Does not matter if the doors are wide open or just ajar. I had that happen to me, so I took some duct tape with me, pushed in the doors until a click was heard and the unit started. Then I held the doors closed with several lengths of the tape.

[buffalobill]

some mechanical thermostats have a separate off switch lever at bottom. or pull off thermostat cover and look for insect problem. if you have a simple 2-wire thermostat: disconnect thermostat's 2 wires and measure 24 volts ac on the wires. the thermostat connects the

2 wires when it calls for heat.

fuzzy57 wrote:

[m Ransley]

Use a volt meter to be sure you have power at the furnace, check the thermostat again to be sure its calling heat.

[maradcliff]

Is there a switch that is still set to AIR CONDITIONING? Be sure to flip it to HEAT. You can always take the thermostat off the wall and touch the two wires together. (no you wont get a shock from 24 volts). Of course if you have more than 2 wires (some do), I am not sure what to say.

One other thing. Next to the furnace is likely a switch. Is it on? Is the breaker on that feeds the furnace?

Mark

[Stubby]

Sometimes there is an emergency cutoff switch on the wall near the furnace.

[flansp78]

If you have never worked on OR understand how a gas furnance works, call for service before you blow yourself up. It amy cost you a few bucks, but the peace of mind knowing that it was fixed properly is priceless......

[Stubby]

I hate to say it but that is an obvious solution. I'll bet fuzzy57 asked the question here because he/she cannot afford an unnecessary service call.

[flansp78]

Well, I suppose if he/she blows up, then I guess they don't have to worry about the heat. NO excuse.....You don't put yourself or others in danger because you can't afford a service call. And if he/she doesn't understand what they are doing then how would they know if the service call is unnecessary?

[Edwin Pawlowski]

What type of thermostat? If it is a programmable one with a battery, it may be as simple as putting in a new battery. It may have just enough power for the display, but not enough to trip the contacts for heat. BTDT.

[Edwin Pawlowski]

Oh stop being a worrying nanny. There are things that can be done by any homeowner before calling the service tech. Heating appliances have all sorts of safety devices built in to them. Checking contacts, thermostats and switches will not cause the main gas valve to open accidentally or to blow up anything. Rather than stop others, educate yourself and put your fears to rest.

[flansp78]

Ya listen to you. You've probably screwed up a number of things in your house and others. The point is, if you don't understand how it works, leave it alone and call someone who does.

[Edwin Pawlowski]

Yes, you should listen to me. Have I ever screwed up something? Yes, of course. But I've learned hot to fix many things a low or no cost and have saved thousands of dollars over the years. Every project is a learning experience. Any wiring I've done has been inspected and approved. Any plumbing I've done has been inspected and approved.

There are many things I don't understand, but I take a little time, follow the wires, follow the pipes, and find solutions to problems. I make a pretty good living at finding solutions to problems. Perhaps you have a life as a pencil pusher in an office and have no uderstanding of things mechanical. That is OK, we all don't want to learn everything, but don't admonish others that do want to learn.

After sitting for the summer, many a solenoid valve will stick. A tap of a hammer can save a $150 service call. Thee is nothing unsafe about that. Checking hte batteries of a thermostat is not unsafe. Checking the position of switches is not unsafe. I did not recommend that pipes be opened up.

Educate yourself. You can save a lot of money.

[maradcliff]

This is one of my pet peeves on this NG. Everyone knows that they can call a professional. so why do people even bother to post such a thing. The whole point of this NG is to find solutions for doing our own repairs. Yes, on occasion I have read someone doing something that does sound dangerous and have myself suggested they get a pro. But messing with a thermostat is definately not going to blow anything up. And for the record, calling a furnace pro will cost much more than a FEW bucks. They are not cheap. Homeowners should be able to do minor repairs, unless they are millionnaires.

For the OP.

1. make sure the breaker is turned ON for the furnace
2. Make sure the switch on, next to, or near the furnace is turned ON
3. be sure the thermostat is set to HEATING, not to AC.
4. turn the thermostat as high as it will go and see if the furnace lights. (turn it back down after).
5. If you have a programmable thermostat, set it to MANUAL or (on mine), it;s called HOLD.
6. As a last resort, remove the thermostat and either try a different one, or temporarily short the wires together if there are only 2 of them.
7. If you have any electrical knowledge, there is a transformer in the furnace that supplies 24 volts. A test meter can be helpful to see if there is voltage.

[maradcliff]

Let me guess..... The last time you tried to do a home repair, you tried to paint a wall, spilled the paint on your couch and tv, and broke a window when the defective ladder broke, you fell 3 feet, broke your spine and spent the next 5 years in traction. Plus when the paint brush hit you in the head you got a brain concussion. Now, you are in too much pain, dont have a couch or a tv to watch, so all you can do is sit in front of your computer posting scarey messages to people trying to do their own repairs. I guess you never understood how a ladder or bucket of paint works, so you should have left them alone.

[fuzzy57]

Thanks, folks. I will try all suggestions and will not open or mess with ANYTHING that I don't understand.

[mm]

If there are 5 connect them all together. Let God sort them out.

I think I heard this advice in a war movie, probably during the heating and air conditioning scene.

[flansp78]

I've built and fixed more things in a week then you'll see in a life time......Sonny. I've watched many people play with gas only to screw it up and cost themselves more money. Most of the time the money ends up in my pocket. I agree that there are plenty of people out there that can fix many things, but when it comes to something of this nature, leave to the Pros......I'm sure some day I'll read about you!!!

[Edwin Pawlowski]

Please get back to us with the resolution. If we don't hear from you, we'll look in the newspapers for houses destroyed by gas explosions.

[mm]

I was working on that AC last Sunday, and my friend started complaining that before the furnace fan worked and now it didn't.

I may have touched the wrong two wires together and blown a fuse in teh furnace. They cost a quarter and there was a spare taped inside the furnace by the manufacturer.

Before we found the problem, I said, Don't worry, when it's fixed, everything will work.

That's sort of obvious because otherwise it woudn't have been fixed. But the upshot is that after another 15 minutes, I was 10 minutes away from saying it was the contactor. I have a spare I stripped out of a discarded compressor, and he'll be fixed in another 20 minutes.

I've never diagnosed this part before, and like you say, every project is a learning experience.

I divide my amateur days from my skilled amateur days, not so much because I make fewer mistakes, but because I always have a way to get out of it now when I do make a mistake.