Thank you all for your answers the heater comes on now. Unfortunately, I had to go back to the old two-wire mercury thermostat because the fan that distributes the heated air through the house doesn't come on. The new thermostat has terminals marked R, W, G, and Y. The exhaust fan for the unburned gases and the furnace itself both come on. Do I have to jumper something to get the distribution fan to come on?
2007-03-21 22:30:18 · 4 answers · asked by Anonymous in Home & Garden ➔ Maintenance & Repairs
There may be a default setting on your thermostat that has it trying to run an electric system. You may need to recheck your directions and make sure you have the right setting.
2007-03-22 09:14:05 · answer #1 · answered by Anonymous · 0⤊ 1⤋
On a gas or oil furnace, the burner comes on first, then the fan comes on after either an electronic time delay or a thermal switch in the furnace.
The new stat should have worked.
You apparently don't have A/C (at least on this stat)
If you are wanting to run the fan continuously, you probably will have to add a separate fan relay to run the fan by itself, unless the furnace has a G terminal and you have extra wires in the t'stat bundle. Otherwise, it will only come on with the heat.
R-W is heat, R-Y is cool, R-G is the fan.
You said the exhaust fan for the burners comes on, telling me the furnace is new enough and should have a G terminal on the circuit board in front of the blower on the bottom of the furnace. If you have an extra wire in the bundle, hook G up on the stat and the furnace.
2007-03-24 10:28:27 · answer #2 · answered by Obsean 5 · 0⤊ 0⤋
No you do not have to jumper anything as the fan that forces the air through the vents in your house is controlled by something else on the furnace...once the furnace starts up..the combustion fan comes on and blows air through the firebox ....you said it was doing this....as the furnace heats up their is a switch called a fan & limit switch or it might just be a fan switch could be thermal or time delay start that turns the fan on when the furnace reaches a preset temperature usually about 150 deg....if fan still dont come on either the fan switch is bad or the fan motor is bad....you should be able to put the new thermostat back on because it does not have nothing to do with problem...
2007-03-25 19:17:41 · answer #3 · answered by Anonymous · 0⤊ 0⤋
I'm not sure I understand you completely. It sounds like you have two wires to your t-stat(red & white)but, you would like to run your blower continuiosly. If this is the case then you will need one more wire. That will have to hook ot the G terminal on the t-stat and furnace. However, if you ever plan on getting A/C then you will need another wire for that(total of four)so you might as well pull a four wire right away. I hope I understode you correctly and this answers your question. Good luck.
2007-03-22 08:18:50 · answer #4 · answered by mike c 3 · 0⤊ 0⤋