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didiathome
Nov 6, 2009, 07:32 PM
I've just bought a new programmable thermostat. In the installation guide, it says "The wires are usually designated W, Y, G, RH, RC, O, B, H1, H2."
But, in mine, a Coleman system, they are designated as W2, Y, G, O, B, L, E, X, R. How should I make them match?
Thanks!

Joshdta
Nov 6, 2009, 07:47 PM
Are there more terminals on the new stat other then the ones you have listed?

didiathome
Nov 6, 2009, 07:48 PM
Nope, that's all I have

Joshdta
Nov 6, 2009, 07:51 PM
What does the instructions say the h1, and h2 are for?

didiathome
Nov 6, 2009, 07:54 PM
H1 and H2 are for an humidifier... But, I don't think my system is equipped with an humidifier

Joshdta
Nov 6, 2009, 07:57 PM
Does this new stat say it will work for 2 heat 1 cool? Or just 1 heat 1 cool with heatpump?

didiathome
Nov 6, 2009, 08:05 PM
It says:
- automatic heating or air conditioning control
- for central heating systems
- 5+1+1 day programmable thermostat

Joshdta
Nov 6, 2009, 08:08 PM
Inless it says 2 heat it will probably not work for you. You will have to get a 2 heat stat to get your electric furnace and heatpump to both work

didiathome
Nov 6, 2009, 08:12 PM
Ok, so I will put everything back in the box and go back to the store!

KISS
Nov 6, 2009, 08:25 PM
Your new stat doesn't have the ability to set the furnace to Emergency Heat - The E terminal is missing

X is probably (C) or common which is sometimes used. Not used if the thermostat is powered by batteries alone.

L is an indicator - has various uses, not needed.

Ususllay you have O/B not O and B. SOme zoning controls require both. It's rare to find them. You generally program how O/B behaves. It usually goes to the reversing valve.

On the new stat Rc gets conncted to Rh and it becomes R.
H1 and H2 is a dry contact for a humidifier.

W could connect to W2


Biggest problem your missing E. E forces the heat pump off and uses the strip heaters alone. Make sure you need both O & B.

Wrong stat. You need one with Emergency heat.

didiathome
Nov 12, 2009, 04:17 PM
I finally bought a new thermostat that should be oki. But I still have one last problem:

Wires existing on my old system : W2 ; Y ; G ; O ; B ; L ; E ; X ; R
Wiring suggested: W2 - Aux ; Y - Y ; G - G ; O - O/B ; B - C ; L - L ; E - E ; X - (C or E, already used!); R - R
So, I have a problem with my X!
The only other plugs available are RC and Y2.

"KeepItSimpleStupid" wrote : "X is probably (C) or common which is sometimes used. Not used if the thermostat is powered by batteries alone."

- That means that if I use batteries, I can use just without wiring it?

Thanks!

KISS
Nov 12, 2009, 05:20 PM
Yep. Is your unit a Trane by chance?

You also need to jumper Rc to R and possibly Y2 to Y on the thermostat. Rc to R is a necessity, otherwise the fan and AC won't work.

didiathome
Nov 13, 2009, 07:02 AM
My new thermostat is a Honeywell.

The jumper between Rc and R is already there, but not between y2 and y and there is no mention about it in the instructions.

KISS
Nov 13, 2009, 08:02 AM
You didn't mention the model of the thermostat. Y2 is second stage cool. If you can set the tsat to 1 stage cooling, that would be best.

I believe Y2, unconnected will be fine.