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gandwadventure

Active member
Joined
Feb 18, 2013
Posts
26
Location
Cartersville, Georgia
I have posted before but I really need someone to help me.
I need to change the Coleman-Mach residential thermostat with the 12 wire , to a Honeywell RTH111 non-programmable thermostat.
I don't know how to copy and paste the website to see the wiring for the RTH111 Honeywell.
I have seen the post with the changeover  from Coleman-Mach to Ritetemp, but cannot use that one.
Please, can anyone give me some diagram or instructions on where each of the existing 12 wire would connect to new Thermostat?
Thanks in advamce.
PS. The system in the Winnebago is a True Air central heating and Air heat pump with Propane gas switch over if temp is below certain degree. (typical heat pump)
 
I just looked at the install instructions for that thermostat and it won't switch to your propane furnace ("emergency heating.")  That one is way too basic.
 
I just looked at the install instructions for that thermostat and it won't switch to your propane furnace ("emergency heating.")  That one is way too basic.

Mr Canfield: could you post a Honeywell digital that would work and the wiring diagram to use it?
Thanks
 
You said you "need to change". Does your existing thermostat not work, or are you trying to achieve something else with a new one? Does it have to be a Honeywell? You can get replacement Coleman 12-wire thermostats, e.g. at http://eldonrv.com/Coleman-Mach-Thermostat.aspx
 
Gary RV Roamer said:
You said you "need to change". Does your existing thermostat not work, or are you trying to achieve something else with a new one? Does it have to be a Honeywell? You can get replacement Coleman 12-wire thermostats, e.g. at http://eldonrv.com/Coleman-Mach-Thermostat.aspx
Click to expand...
I don't like the switches on the Coleman, plus the digital ones with the switches work better for me.
There is nothing wrong with the Coleman i have except the cheap off/ cool/ heat / gas switches.
I have been told i can change it out, but so far,  have not been able to get a wiring diagram for the Honeywell to Coleman crossover.
 
The slide switches on the Coleman Mach thermostat are a design/engineering joke  ::).  I haven't forgotten about wiring help, been really busy here at the ranch.
 
John Canfield said:
The slide switches on the Coleman Mach thermostat are a design/engineering joke  ::).  I haven't forgotten about wiring help, been really busy here at the ranch.
Click to expand...
Thanks. Just looked at your location. Are you one of them Ole Texas Longhorns? I live down in the South, north of Hotlanta, close to Lake Alltoona. Go Ga Bulldogs!!!!
Didn't mean to change subject (ha)
 
gandwadventure said:
Thanks. Just looked at your location. Are you one of them Ole Texas Longhorns?..
Click to expand...

Roger that!  UT-Austin graduates:  dear wife, wife's brother/sis-in-law/mom/dad/two cousins.  I took some undergrad classes there but graduated from Webster University.  I'm the family oddball  :D.
 
Okay - I had a Honeywell RTH8500 Series touch screen thermostat in the house that I replaced with an Ecobee, looked at the wiring and here's what I think you need to connect to a programmable thermostat:

Honeywell thermostat.......CM thermostat wire colors

RC/R ---------------------->  Red/white and red  (edit - added red)
W  ------------------------>  White/black
Y -------------------------->  Yellow
G -------------------------->  Black
C -------------------------->  Blue/White and blue (edit - added blue)
Y2 ------------------------->  Orange
W2 ------------------------>  White

Y, Y2 calls for compressor 1 or compressor 1 and 2 in cooling mode, W calls for electric heat (I think both compressors run IIRC), W2 calls for emergency heat (gas).

Do not option the thermostat for a heat pump, select in Honeywell terminology Heat/Cool Multiple stages - wires on Y, Y2 and W, W2 (function 0170, setting 8.)

Hope this gets you started.

 
John Canfield said:
Okay - I had a Honeywell RTH8500 Series touch screen thermostat in the house that I replaced with an Ecobee, looked at the wiring and here's what I think you need to connect to a programmable thermostat:

Honeywell thermostat.......CM thermostat wire colors

RC/R ---------------------->  Red/white
W  ------------------------>  White/black
Y -------------------------->  Yellow
G -------------------------->  Black
C -------------------------->  Blue/White
Y2 ------------------------->  Orange
W2 ------------------------>  White

Y, Y2 calls for compressor 1 or compressor 1 and 2 in cooling mode, W calls for electric heat (I think both compressors run IIRC), W2 calls for emergency heat (gas).

Do not option the thermostat for a heat pump, select in Honeywell terminology Heat/Cool Multiple stages - wires on Y, Y2 and W, W2 (function 0170, setting 8.)

Hope this gets you started.
Click to expand...
Ok. I am kinda "dumb" , don't understand "Do not option the thermostat for a heat pump, select in Honeywell terminology Heat/Cool Multiple stages - wires on Y, Y2 and W, W2 (function 0170, setting 8.)"  Also what do I do with Red, Purple,grey,grey and Blue wires that is left from Coleman _mach? wiring?
Thanks again. I think I am making progress, but not quite there yet.
 
gandwadventure said:
Ok. I am kinda "dumb" , don't understand "Do not option the thermostat for a heat pump, select in Honeywell terminology Heat/Cool Multiple stages - wires on Y, Y2 and W, W2 (function 0170, setting 8.)"  Also what do I do with Red, Purple,grey,grey and Blue wires that is left from Coleman _mach? wiring?
Thanks again. I think I am making progress, but not quite there yet.
Click to expand...
Sorry, red is connected to red/white, blue is connected to blue/white,  I corrected my post above.  The two gray wires aren't needed, they are the freeze switch.  Purple wire is fan low speed, don't need it.

Sorry, I can't help you understand this any more, you are going to have to do some study on your own and review my page on changing out the CM thermostat.
 
Thank you so much. I think I got it now. I will report on the results when i get it installed.
B T Y, I talked to Winnebago factory and told them about the thermostat they installed and how poorly it was designed, but they never offered any suggestion. I was checking out the RV last week and when i turned off the heating and cooling system, or I thought i did, the system came back on after a short period of time. I had to wiggle the off switch on the thermostat to get it to go to the off position.
Still say it is a bad thermostat design.
Off my soap box, have a good day
 
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