please tell me what color the following wires connect to the lettered terminals on a thermostat. blu grn red w

Question

there are 4 wires to connect to the thermostat red green blue and white the letters of the terminals are g y w rh rc

Answer 1

Hi
To the best of my memory here is how it SHOULD go...

G = Green (ground?)
Y = Blue (don't ask why) (fan or blower?)
w = white (Neutral?)
rh = red - heat (hot to heat term at furnace)
rc = red - cooling (Hot to cooling term (A/C) at furnace)

Now, that said, the question marks are because there is not always standard wiring.

Best way is to check the other end of that thermostat wire where it comes out at the furnace. It will go into a control box. Take a flash light. Pull the cover off of that control box and check which color wire goes to which terminal - they should be labled similarly. Write down what goes to what and hook up thermostat the same way.

Double check the instructions that came with the thermostat if you are hooking up a new one. Not only will they state which wire should go where but they should also state which terminal does what (ground, hot, etc,) and that explanation should line up with what you wrote down while looking at the furnace control box.

Note that if you do not have A/C, or a seperate fan only switch on the thermostat, then some of the wires will not be used and may be disconnected at either or both ends.

BTW, if you remove an existing thermostat to patch the wall, paint or paper, just clip the wires off about an inch out from the terminals. That way you'll know which color went where when it is time to hook it up again.

Answer 2

Let see 4 wires 5 terminals.

There may be some one out here that could talk you through this.
But don't count on it.

You will have to study the diagrams that came with the thermostat.
And it would help if you had the diagrams for the AC & furnace.

If any of the wireing diagram makes any sensene to you you may have a chance of doing this your self.

It comes down to which spot on the terminal goes to what spot on the furnace & which go to the AC.

Match the colors of the wires at the AC & furance to the posts on the thermostat & you are home free.

You can do this all by trial & error. Number the wires 1-2-3 & 4
Call the post on the thermostat rh - rc -green-yellow-white

Check but I think one wire would go to both rh & rc.
(heat & cool) You woukd put a short piece of wire between those two post & fasten one of the other wires to one of the posts.

Then list all the possible combinations: IE

(1- rh &rc ) 2 green 3 yellow 4 white
(1 rh &rc ) 2 yellow 3 white 4 yellow
etc etc I think that there would be about 24 different combinations
Try them all & you may get lucky.

If you don't get lucky you can always call a heating or AC man.

Just study the diagrams good. And where the wires are hooked up at the other end. It will help if you keep notes of the steps you are taking.

Answer 3

it doesnt matter if the wires are pink with pokadots. the important thing is that the wire connected to the w terminal on your furnace is the same wire thats connected to w on your t-stat and so on. Generally, white goes to W, green to G, red to R and yellow to Y. It sounds like in your case blue is substituted for yellow so it would go to Y. Always turn the power off to your furnace before messing with t-stat wires. you could burn-up your entire low volt system. But look at your furnace to see how the colored wires are coordinated, write it down, then hook up your t-stat the same way. ok I better clarify. R is your power, G is fan, W is heat, Y is cooling. if you have rh and rc just use a small piece of low volt wire and jump rh over to rc

Answer 4

Put the white wire to w, the green wire to g, the blue wire to y, and the red wire to either rc or rw. You will then probably have to install a jumper wire from the rc terminal to the rh terminal. The rc terminal is for the cool cycle and the rh terminal is for the heat cycle. Check your instructions for a wiring diagram to see if the jumper is needed.

Answer 5

dont trust the colors. you can damage your system easily. hire a professional first . or you will later for a lot more.....I know... I'm an electrical contractor