Thermostat swap to digital

[Watsons]

Hi all, There is some pretty good info on the forum regarding this and thanks to all who have contributed.
It gave me enough info to want to do this swap.
What I am trying to find before I start this mod is the wiring diagram for the existing Coleman Mach in our 2017 339 FLQS so I can look at the new one and figure our wires before I start the project.
A little gun shy with electrical so being cautious and want to ensure my chosen digital one will work before i start.
Can anyone offer any help?
Cheers

[jlechmanik]

Since the one you chose is non programmable why not just go with the Coleman digital model? Then the wires are the same. And the mounting screws....

[Watsons]

Originally Posted by jlechmanik

Since the one you chose is non programmable why not just go with the Coleman digital model? Then the wires are the same. And the mounting screws....

Good question, but here are my thoughts.
The Coleman's are twice the price, small screen, no back-light and look like they are from the 60's.
Other than that I don't see a problem with them. Lol

[Camper_bob]

Originally Posted by Watsons

Good question, but here are my thoughts.
The Coleman's are twice the price, small screen, no back-light and look like they are from the 60's.
Other than that I don't see a problem with them. Lol

True.

But the Coleman 'stat works, and you don't have to hack it. It is literally plug and play.

[TWP723]

How many wires are on the original t-stat?

[Watsons]

Originally Posted by Camper_bob

True.

But the Coleman 'stat works, and you don't have to hack it. It is literally plug and play.

Valid point sir, but finding out what wires do what function in the RV to match with the residential unit can hardly be called a 'hack'. Modification and improvement yes, hack, no.
Cheers

[Watsons]

Originally Posted by TWP723

How many wires are on the original t-stat?

Hi TWP 723, that's what I am asking in my original post actually. I would like to find the wiring diagram for my unit from someone before I even take the front off the existing one so I am prepared with proper residential thermostat and knowledge.
I will let this post soak for a few days to see if someone can chime in with the info. If not I will dive in..
Cheers

[troutslayer]

O.K. so I'll chime in here. I bought an other brand digital thermostat from HD and never could get the wiring right. The closest I got was everything working correctly EXCEPT the A.C. fan wouldn't shut off. Bit the bullet and got the Coleman Mach digital and everything works like it should...but no backlight, dammit! Hope you have a better experience .

[Magnolia Tom]

The reason camper bob says it’ll be a “hack” is because you will need to add some type of switch for the hi/lo fan speed. Residential t-stats don’t have this built in like Rv stats do.

[TWP723]

Originally Posted by Watsons

Hi TWP 723, that's what I am asking in my original post actually. I would like to find the wiring diagram for my unit from someone before I even take the front off the existing one so I am prepared with proper residential thermostat and knowledge.
I will let this post soak for a few days to see if someone can chime in with the info. If not I will dive in..
Cheers

Gotchya! Should be a 6 wire thermostat. Not much different from a residential except for no emergency or aux heat. Most common reasons for other t-stats not working is they are wired wrong. Not hard at all.


green & gray=fan
yellow=compressor
blue=common
red=positive
white=heat

[Watsons]

Originally Posted by Magnolia Tom

The reason camper bob says it’ll be a “hack” is because you will need to add some type of switch for the hi/lo fan speed. Residential t-stats don’t have this built in like Rv stats do.

Appreciate the input. We decided we can do without the low setting so no problems there.
Cheers

[Watsons]

Originally Posted by TWP723

Gotchya! Should be a 6 wire thermostat. Not much different from a residential except for no emergency or aux heat. Most common reasons for other t-stats not working is they are wired wrong. Not hard at all.


green & gray=fan
yellow=compressor
blue=common
red=positive
white=heat

Thanks bud, now as long as they color coded mine the same as yours I should be able to knock this off. Will pick up the replacement tomorrow, check its requirements and work on it Sunday with results (good or bad) shortly thereafter.
Cheers

[Camper_bob]

Originally Posted by Watsons

Appreciate the input. We decided we can do without the low setting so no problems there.
Cheers

It's a good point there. I don't even use the "Lo" setting on mine. If the AC is running, it's hot outside, no sense messing with low speed fan! LOL!

[RVhiker]

This may have some information that will help:Coleman Mach Thermostat.

[Watsons]

Originally Posted by RVhiker

This may have some information that will help:Coleman Mach Thermostat.

Will check that out...thanks!!

[TWP723]

Originally Posted by Watsons

Thanks bud, now as long as they color coded mine the same as yours I should be able to knock this off. Will pick up the replacement tomorrow, check its requirements and work on it Sunday with results (good or bad) shortly thereafter.
Cheers

No guarantees. LOL. I just replaced the old Baystat in my house with a Honeywell 5-2 t-stat and it was an absolute nightmare. Connected it exactly like the directions instructed and nothing. Turns out, the new Honeywell thermostats don't require jumpers and I had a hard time trying to figure it out. Finally got it right.

[Johnyb6633]

the wires match fine. I used a simple Honeywell TH3110D1008 Pro Non-Programmable Digital Thermostat. yeah i dont have A/c hooked up to it. But its a simple upgrade and works fine with the heater in my jayco.


see pics

[r1johnson]

I'm not sure a residential thermostat will work in your camper, I believe it operates on a 24 volt system and the camper is only 12 volts.

[Johnyb6633]

Originally Posted by r1johnson

I'm not sure a residential thermostat will work in your camper, I believe it operates on a 24 volt system and the camper is only 12 volts.

The thermostat has nothing to do with a campers 12 volt system. And residential constructions are 110. a thermostat is merely an automatic on off switch powered by 2 Double A batteries.
If you looked at my post I have one installed and it works WAY better then the Coleman my rv came with.

[Magnolia Tom]

Originally Posted by Johnyb6633

The thermostat has nothing to do with a campers 12 volt system. And residential constructions are 110. a thermostat is merely an automatic on off switch powered by 2 Double A batteries.

If you looked at my post I have one installed and it works WAY better then the Coleman my rv came with.

The batteries in your home t-stat is for backup and memory functions. It gets power from the air handler or furnace unit and it is stepped down to low voltage. Old dial thermostats didn’t have batteries yet they still got power from the air handler or the furnace.