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timothy_s_alexander
Thermostat won't work

My thermostat will not turn my furnace on when I put the temperature gauge under the current house temp. But the furnace will turn on if I go downstairs and tap the pipe leading to the furnace. Any suggestions on what I can do to fix this. It causes the house to get very cold when I'm not home because it won't start up when the temp drops below the level set on the thermostat until the pipe is tapped. Thanks in advance for whatever help you can give.

Tim

Sten
Re: Thermostat won't work

First off you want to adjust your stat higher than the temp. your house is at for heat and lower than the temp your house is at for cooling, sounds like you may have that backwards. Second is I don't know of a pipe that would cause your furnace to come on by tapping it. Have you tested you stat or the batteries in it. What you could do is try jumping out your furnace at the stat. to see if it comes on. Follow the instructions I give carefully.

BEFORE YOU DO ANY OF WHAT IS BELOW MAKE SURE THE RIGHT WIRES ARE GOING TO THE RIGHT PLACE OT THE STAT. COLORS SHOULD BE RED AND WHITE. RED IS YOUR ***** AND WHITE IS FOR HEAT. THERE SHOULD BE AN R AND A W WHERE THE WIRES ARE CONNECTED. DON'T TOUCH THESE WIRES TO ANY OTHERS, ESPECIALLY THE BLACK OR YOU COULD BLOW A TRANSFORMER.

1. Take the faceplate off your stat.
2. Look for the two wires that control heat, they should be the
red one and white one.
3. With a very small screwdriver loosen the set screws that hold
theses wires in place.
4. Carefully twist these two wires together.
5. You may have to wait about a min. if your furnace has a delay.

If your furnace works after doing this but didn't work before then chances are your stat is bad.

If it still didn't come on there's one more thing you can check.

1. Put the stat back together the way it was.
2. Trace the wires to your furnace, same color same size.
3. If you found them and you are sure they are the correct wires
loosen them as you did at the stat and take them off, be
and remember which goes where.
4. Take a small piece off wire and attach one end at one screw
and one end at the other, you still may have to wait a min.

If it didn't come on by jumping out the stat but did come on by jumping out the furnace then chances are you have a broken stat wire somewhere between the furnace and stat. It may be in the wall but by chance would they by secured to that pipe your tapping???. If your furnace came on in the second set of Instructions but not the first then look for the broken wire, and I'd check along that pipe if they are attached to it. If none of this worked then you should call an HVAC Contractor. Good Luck :)

canuk
Re: Thermostat won't work
timothy_s_alexander wrote:

My thermostat will not turn my furnace on when I put the temperature gauge under the current house temp. But the furnace will turn on if I go downstairs and tap the pipe leading to the furnace. Any suggestions on what I can do to fix this. It causes the house to get very cold when I'm not home because it won't start up when the temp drops below the level set on the thermostat until the pipe is tapped. Thanks in advance for whatever help you can give.

Tim

What pipe ?
And what lead you to tap this pipe to get the furnace working?

Sounds like you may need a heating professional to check things out.

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