Need assistance - AC fan

[mwebber78]

2013 with Coleman Mach system and thermostat, unit runs on fan but both high and low seem like high. Anyone have wiring picture or diagram or is this normal? I pulled the wiring and can't make heads or tails of the mess back there!

[Rustic Eagle]

I believe the following is the Coleman Mach wire color code:

Red = +12vdc

Blue = -12vdc

Green = Fan High

Gray = Fan Low

White = Furnace

Yellow= Compressor

The high/low speed fan for the A/C (doesn't work with furnace, one speed only) there is very little difference, but in low it is a little quieter.

On Edit: Found this Coleman Mach Install document: http://www.klenger.net/RVing/HVAC_Hu...stallation.pdf

Bob

[mwebber78]

So with AC off just using fan you only have one speed?

[Rustic Eagle]

Ahhh, good question. I never even paid attention to mine because I never used the "fan only" cycle..., but since then I have upgraded to a Hunter digital stat.

Bob

[Nighthawk 96]

in fan only cycle there is a high and low, but the difference is very small. You can have the fan running all the time in a/c mode, however in heat mode the fan comes on only when the heater is on. It is a different fan, blowing air in low wall mounted or floor vents.