furnace thermostat Vista 29VE

[bwlowry615]

Trying to change analog thermostat to one with digital display & programming.
My question is about the wires. The Coleman Mack has wires R-red; Y-yellow; W-white; GL-gray; GH-green; B-blue. (So labeled on circuitboard.) The install directions on the Heagstat 705 do not show a gray wire connection. It does have a C (for common wire) terminal and a G terminal.
Do the Green & Gray attach to the C & GH connectors and in what order?

[ThomB]

Not familiar with that model thermostat but I do have a question about your Coleman Mach.
Is it a heat pump? My Mach (3) is a heat pump and has "gas heat / electric heat" on the selector switch which (based on a google search) that thermostat doesn't look to have.

Does it have a 2 speed motor? (I'm guessing this may be where you have extra wires - High and Low speed?) I've seen on the forums where people will wire in an external switch so you don't lose the speed selector.

[bwlowry615]

Just have furnace & roof A/C unit.
It is a 2 speed fan. One speed would be fine.

[ThomB]

Originally Posted by bwlowry615

Just have furnace & roof A/C unit.
It is a 2 speed fan. One speed would be fine.

OK, then me looking at my setup probably won't help you as we have a heat pump unit, sorry.

[creativepart]

There are supposedly a few thermostats that can be substituted for the Coleman-Mach unit, but I don't think any are straight forward or problem free. Especially running AC Heat Pumps and separate gas heaters.

I know some have done it - but I hear you have an issue with fan speed on the AC unit.

Do, a broader search on Google or even on YouTube. It will depend on your CM Model and features.

This may help:

https://www.youtube.com/watch?v=T2S8Vq5diAM

[Morich]

My first question might be to ask if this is a recommended unit for RV's? Very easy to get something designed for home use which is quite different than RV.