Coleman Mach RV Comfort Thermostat

Most of the Coleman Mach docs, sheets etc can be found here.

Coleman Docs

Will help if you know your model number.

RustyScupper wrote:
Yesterday getting the rig ready for the season and fired up the electric heat strip in the AC unit and it worked fine except that the propane furnace also came on.

I have the Coleman Mach RV Comfort Thermostat and I assume that it is the little selector slide switch is malfunctioning allowing both heat sources to run at the same time.

I have had issues in the past where the propane furnace would run and continue past the heat setting and not shut off.

Any thoughts if I am on the right track?

Hi Rusty, I too have theColeman Mach rv stat. It operates in the same manner. I'm told that's normal. Mine is coupled with a heat pump. I have an Alfa38 5er. No manual provided by Camping World when purchased. ( they had them b4 signed papers, after papers signed oops they didn't have them, ya go figure!) So I don't know the btu value. My problem is: the gas furnace fan motor (12v) now runs constantly since service from CW. I'd rather not take it back there if I can easily remedy it myself.
I do suspect the thermostat.

RustyScupper wrote:
Doug- just read you attachment. I think you nailed it. Just the right conditions (temp wise) that this occurred. I thought the heat strips were just as efficient. Learn something new everyday. I will do more testing.

Heat Strips are about 5600 BTU's. The Heat Pump is the AC rating(13.5 or 15k BTU). Doug

Doug- just read you attachment. I think you nailed it. Just the right conditions (temp wise) that this occurred. I thought the heat strips were just as efficient. Learn something new everyday. I will do more testing.

kampinguru wrote:
I had an issue with my unit when I first got it where I would turn on the AC and it would come on. After a while, the furnace would kick in and both would be running. It turned out to be a screw through one of the wires in the unit but they couldnt tell where. They ran new wire from the thermostat to the AC and to the furnace to correct it.

That would confirm the worst possible situation. Not sure If I would be able to rerun wires. Thanks for your insight.

I had an issue with my unit when I first got it where I would turn on the AC and it would come on. After a while, the furnace would kick in and both would be running. It turned out to be a screw through one of the wires in the unit but they couldnt tell where. They ran new wire from the thermostat to the AC and to the furnace to correct it.

LadyRVer wrote:
On my unit, if I set the thermostat for more than a 3 degree difference (in the elec heat mode) the furnance will kick on with the elec heat until it catches up, then furnaces stops and elec heat takes back over.

If major difference in coach, I just start with propane furnace, wait until it reaches about 45-48 outside, then switch to elec heat to maintain.

Do you have the Dometic Roof units with the Dometic Tstat? Most Monaco's used Dometic. Doug

As I stated, the Heat Strip parameters are identical to the Heat Pump parameters. Doug



http://www.rvcomfort.com/rvp/pdf_documents/t_stat_electric_heat_function.pdf

LadyRVer wrote:
On my unit, if I set the thermostat for more than a 3 degree difference (in the elec heat mode) the furnance will kick on with the elec heat until it catches up, then furnaces stops and elec heat takes back over.

If major difference in coach, I just start with propane furnace, wait until it reaches about 45-48 outside, then switch to elec heat to maintain.

Hmmmm - This is the first time it has happened. Maybe it is suppose to work that way. Might have to think this one thru before I buy a new thermostat. 90% of the time I am boondocking and no AC so this is the first time it has happened and may be an "undocumented" feature.

On my unit, if I set the thermostat for more than a 3 degree difference (in the elec heat mode) the furnance will kick on with the elec heat until it catches up, then furnaces stops and elec heat takes back over.

If major difference in coach, I just start with propane furnace, wait until it reaches about 45-48 outside, then switch to elec heat to maintain.