# Wiring a Thermostat



## TwoFour (Oct 31, 2011)

So after reading all the "easy" installation instructions that came with a new Hunter thermostat and surfing the internet, I am clueless...

I have only 4 wires coming out of the wall: Red, Black, White, and Green.









None of the diagrams match these wires and I've tried a few of the best setups I can find.

Is this really this difficult? I believe I have a Conventional HVAC (Furnace & AC Unit) from York.

Thanks!


----------



## Raylo (Feb 12, 2006)

No, it really isn't difficult. The standard colors are:

R (red): 24vac power from the transformer on the air handler. R and Rc will be jumpered together on the stat.
G (green): blower motor
Y (yellow): A/C compressor
W (white): heat 

The thermostat basically routes the 24 vac from the R to G (to turn on the blower) and either the W (to turn on the furnace on a call for heat) or Y (to turn on the a/c compressor on a call for a/c) depending on the stat mode.

Assuming your installer mostly followed the standards the outlier is the black wire. Go to your furnace/air handler, pull the lower cover (for an upflow furnace) and look for a terminal block that has the same letters... then match the wire colors on the thermostat end to what they are on the air handler end. That's all there is to it.





TwoFour said:


> So after reading all the "easy" installation instructions that came with a new Hunter thermostat and surfing the internet, I am clueless...
> 
> I have only 4 wires coming out of the wall: Red, Black, White, and Green.
> 
> ...


----------



## TwoFour (Oct 31, 2011)

Raylo, Thank you! I think I confused myself with all the diagrams but I followed your advice and so far so good...

You Rock!


----------



## Raylo (Feb 12, 2006)

Excellent! Glad to help.


----------



## wolfen1086 (Oct 4, 2007)

Do yourself a BIG favor, draw a picture of how its wired once you get it right and save one copy in a fire proof box, one on the computer and one in a safe deposit box at your bank






trust me


----------

