Replacing analog thermostat to digital

[pokey]

I want to replace my analog Dometic Duo Therm thermostat with a Honeywell non programmable digital one. Can someone please post a picture of the correct wiring from the analog to the digital or add the correct wiring? From reading reviews on Amazon I know that the red is not used because the thermostat runs off of batteries and there's only one option to run the fan either on high or low. Picture of the wiring from the analog and link to the thermostat I'm looking at. Thanks in advance all.


Honeywell RTH5100B 1025 Deluxe Manual Thermostat

[pokey]

Originally Posted by pokey

I want to replace my analog Dometic Duo Therm thermostat with a Honeywell non programmable digital one. Can someone please post a picture of the correct wiring from the analog to the digital? From reading reviews on Amazon I know that the red is not used because the thermostat runs off of batteries and there's only one option to run the fan either on high or low. Picture of the wiring from the analog and link to the thermostat I'm looking at. Thanks in advance all.


Honeywell RTH5100B 1025 Deluxe Manual Thermostat

This from someone on Amazon:

For using this in an RV if you want high fan when using the A/C all the time simply twist your brown and blue wire together making a splice of sorts and put it under the G contact. Brown wire only if you want low fan. Without adding a toggle switch as some YT videos show you'll have to pick a fan speed you want. I'll also note that since RV's have a ground wire (green) you'll need to put this under the R/ Rc contact for your A/C and Furnace to work. Simply cap, or tape off your red wire as this thermostat does not require nor use control voltage. Which for those of you wondering most RV's thermostat control voltage (Red wire) is around 8v.
If this thermostat becomes unavailable in the future, for my fellow RVer's, the type of thermostat you're looking for is one that requires batteries for operation. If it says it needs 24v constant power it will not work in an RV application.

Would this be the correct way to wire to battery operated digital?

[Funengineer]

This is what I used. I have since purchased a On-Off-On mini switch that I will install when it’s warmer to activate both high and low speeds.

[Bama Rambler]

Below are the instructions for hooking it up. The biggest thing is that Dometic switches the ground, instead of the hot (like every other mfg does) so you hook green to the R/RC terminal.

1. The RC and R terminals that have the factory jumper gets the Green wire hooked to it.
2. White wire goes to the W terminal. It is to turn on the heater.
3. Yellow wire goes to the Y terminal. It turns on the A/C compressor.
4. The blue and orange wire go together in the G terminal. That is the fan. You will have only one fan speed doing it that way and that is high. If you want to keep the two speed selectable fan speeds, you will have to add a two position micro switch with the orange on one side and the blue on the other with the center pin going to G.

[pokey]

Originally Posted by Funengineer

Attachment 218837Attachment 218836
This is what I used. I have since purchased a On-Off-On mini switch that I will install when it’s warmer to activate both high and low speeds.

Thanks for the diagram. I'm planning on just connecting to high fan only that I always use. I just found this.

[pokey]

Originally Posted by Bama Rambler

Below are the instructions for hooking it up. The biggest thing is that Dometic switches the ground, instead of the hot (like every other mfg does) so you hook green to the R/RC terminal.

1. The RC and R terminals that have the factory jumper gets the Green wire hooked to it.
2. White wire goes to the W terminal. It is to turn on the heater.
3. Yellow wire goes to the Y terminal. It turns on the A/C compressor.
4. The blue and orange wire go together in the G terminal. That is the fan. You will have only one fan speed doing it that way and that is high. If you want to keep the two speed selectable fan speeds, you will have to add a two position micro switch with the orange on one side and the blue on the other with the center pin going to G.

Thanks for the info, Doing it like you explained should do the trick and planning on just using it on high fan

[pokey]

Originally Posted by pokey

Thanks for the info, Doing it like you explained should do the trick and planning on just using it on high fan

Thanks guys, What you posted is just what I needed. Now time to order the thermostat!

[Easymoney]

If you are stuck on using the Honeywell I am not sure of the wiring but I replaced my analog with a coleman airxcel 8330-3862 and it was wire for wire fit. you can do some research and find what thermostats are direct replacements for your old analog.





2005 Dodge Ram turbo diesel
2018 Rock 2606WS

[pokey]

Originally Posted by Easymoney

If you are stuck on using the Honeywell I am not sure of the wiring but I replaced my analog with a coleman airxcel 8330-3862 and it was wire for wire fit. you can do some research and find what thermostats are direct replacements for your old analog.





2005 Dodge Ram turbo diesel
2018 Rock 2606WS

I did look at the one that you got. Had I known that it was a direct wiring replacement I would have got it. I've already bought the Honeyewell and from researching, posting here and YouTube now know the wiring. Was your old one the Dometic Duo Therm? That's what I'm replacing. Thanks

[Chuck_S]

Why non-programmable? Saving $10 so you can get out of bed into a cold camper? Get one that's lighted as well. (Press to light.)

I had to wire a separate switch into mine for High/Low fan speed on the ceiling AC. Furnace fan only has one speed.

-- Chuck

[pokey]

Originally Posted by Chuck_S

Why non-programmable? Saving $10 so you can get out of bed into a cold camper? Get one that's lighted as well. (Press to light.)

I had to wire a separate switch into mine for High/Low fan speed on the ceiling AC. Furnace fan only has one speed.

-- Chuck

I've had programmable ones in the past, condos etc. I never used the programming. The one I ordered does light up and no I'll never get out of bed cold! I will set it to 60 when it's cold, hop put of bed and turn it up a bit.

[Villagerjjm]

Hmmm... Interesting posts! I have a spare Aprilaire fully digital thermostat that is fully functional with power supplied by battery. It has dual phase capacity built in for fan speed control. You set a low temperature which will switch on the heat and a high temperature that switches on the air conditioner. It has a humidity control that will operate the system to control the humidity level as it’s own independent setting. Perhaps I may try to hook it up in my Rockwood.

[pokey]

Originally Posted by Villagerjjm

Hmmm... Interesting posts! I have a spare Aprilaire fully digital thermostat that is fully functional with power supplied by battery. It has dual phase capacity built in for fan speed control. You set a low temperature which will switch on the heat and a high temperature that switches on the air conditioner. It has a humidity control that will operate the system to control the humidity level as it’s own independent setting. Perhaps I may try to hook it up in my Rockwood.

If you have an analog in your Rockwood, go for it. It'll be much more accurate

[Easymoney]

In answer to your question, the one I replaced was a Coleman-Mach.
The digital one is so much better. The analog would have AC running until you were freezing, then wouldn't com back on until you were sweating. Most thermostats have a part number on the back or inside the cover to match up a replacement.

2005 Dodge Ram
2018 Rockwood 2606WS

[rockfordroo]

I made the wiring pic in post #3. Be aware that it was for replacing a T-stat on a Coleman-Mach, which switches the positive side.

My understanding is that Dometics switch the negative side, so that wiring diagram may not be applicable to your situation. I'd suggest you do a search for "thermostat" and "Dometic" and see how others have done it.

You might find it easier to simply replace the analog Duotherm with a digital version.

[Larry-NC]

Originally Posted by pokey

Thanks guys, What you posted is just what I needed. Now time to order the thermostat!

So I was reading this thread right after one of the millions of threads on parasitic battery draws. And it got me to wondering. Do digital thermostats are another parasitic draw? If they have a clock and no batteries, they have to draw some current. Possibly more to retain settings, and maybe more to operate the microcomputer, even when set to Off.

Designers of these thermostats have no incentive to make them stingy. They are used in residences and park models where power is always available. The only reason some have batteries is that the original installation did not have a power wire, e.g., a furnace installation that only reason two wires to the thermostat.

[Chuck_S]

Residential thermostats won't work unless they use batteries 'cuz (1) the wiring and transformer ain't there and (2) they use 24v, not 12v.

-- Chuck

[rockfordroo]

Originally Posted by rockfordroo

I made the wiring pic in post #3. Be aware that it was for replacing a T-stat on a Coleman-Mach, which switches the positive side.

My understanding is that Dometics switch the negative side, so that wiring diagram may not be applicable to your situation. I'd suggest you do a search for "thermostat" and "Dometic" and see how others have done it.

You might find it easier to simply replace the analog Duotherm with a digital version.

Try this thread.

http://www.forestriverforums.com/for...ng-164844.html

[pokey]

Originally Posted by pokey

Thanks for the info, Doing it like you explained should do the trick and planning on just using it on high fan

I'm getting ready to install the Honeywell thermostat that I posted here. Quick question, I've been told from posts and see from researching that the green wire goes to the green wire goes to the RC / R terminal with the jumper. The thermostat has separate terminals one for RC and one for R. Which one do I wire the green to? I'm thinking just the R from a video I watched but want to make sure. Thanks!

[Bama Rambler]

Since it has a jumper between R & Rc it doesn't matter which terminal the wire goes under. Just put it under whichever is easiest for you.