Analog to Digital RV Thermostat Upgrade Mod *Explained*

[@TortoiseHareTravel]

Big, big thanks from a Winnebago View owner who thought there must be something better than this sliding switch that gives us either an Arctic blast or nothing! I bought the Honeywell FocusPro 5000 and was starting to think I'd made the wrong choice before watching both of your videos (switching from Coleman Mach to Honeywell). Starting last evening and finishing this morning, I now have a really user-friendly and precise controller installed for my own use and for my RV renters who take "Clio" on the road. Thank you so much for doing the work to find a great solution and for sharing it (and explaining it in detail) to the rest of us! I was intimidated at first by how difficult it was to turn the "red wire" screws on the new Honeywell unit, but I called their help number and decided to use my little screwdriver and strong pliers to make space for the red wire. That worked quite well, and now the new Honeywell is set up and working exactly as I'd hoped!

[@LoveYourRV]

Awesome, that's great to hear. Cheers! Ray

[@justinjones8172]

The fact you explained about the old thermostat needing the blue wire to power the thermostat circuit and the new one did not helped me fix my issue of why I would blow the 7.5 amp AC fuse every time I would switch to the furnace. Thank you!

[@maehay4065]

You made this seam simple! I had a therapist that quit working. I tried replacing the batteries but it still didn’t work. My son came over recently and cleaned the battery coils and now it works like a charm! You must have a natural curiosity seeing how things work! One of my brothers was like this. He turned out being able to repair cars. I just experiment in the kitchen. Thank you for sharing this informative video! 👍

[@BenjaminHansen]

Thanks Ray! We picked up a new-to-us Keystone Laredo 26RLS and needed the thermostat upgraded. I followed your process on our previous Keystone (4 years ago) which turned out great. Now I needed to do it again. This time I will add the high/low a/c fan switch. The Honeywell model you show is getting scarce to purchase (and expensive). I picked up one from ebay as I like the other so much and would not know a comparison. We love our RV.

[@GolfSierra47]

Good job on simplifying a changeover that Honeywell customer service couldn't help with (tried twice). A person should be able to convert from a 6-wire C/M thermostat to just about any battery operated Honeywell thermostat with what you've shown here. One thing H-well customer service did tell me, was that their thermostats are for 24v systems. You can use this on a 12v (RV) system, but only if it is a NEW install. Apparently something happens internally once it is connected to a 24v system, and it won't revert to a 12v system.

[@abyssiniahenry128]

BTW/FYI, I'm not sure if what Honeywell told you about prior 24V install is correct. I bought a Honeywell TH6110D1005/U (Focus Pro 6000) Programmable Digital thermostat off Amazon in "Used-Like New" condition for cheap. You could tell that it had been previously installed by someone (mounting hardware was missing, wall bracket had screw head impressions, terminal screws had some in/some out, all manuals missing etc. and some of the program codes had been changed (they had it set as Cool Only Mode). I reset it back to factory settings and changed the codes to what I needed (added heat mode back in) and it works like a charm in my 2018 Heartland Mallard M28 travel trailer 12V install. Just thought I'd add that for future readers. Cheers.

[@nancyf52]

I had a replacement thermostat go bad too. It wouldn't turn the fan on. Great job Ray.

[@johnw.7584]

Great video. I put one in a week ago and wow I had some many wires. But like you say. Use a voltage meter for all your work. Thk you rock.

[@marshallpoe8087]

Great job Ray. Last year I replaced both of my Coleman-Mach analog thermostats with these Honeywells. They work great.

[@kevinj8258]

Marshall Poe - and they are still working ?

[@truker1970]

I did this on my older rv with no issues so i put one in my 2013 jayco last weekend. At first all worked well, but then the furnace did not run that night. Put my meter on the 12volt leads and only had 1 volt and nothing worked. I didn't know to leave the blue wire off so could i have fried my furnace board?

[@LoveYourRV]

It's strange that all worked well then suddenly quit. Maybe some wires crossed and blew a fuse somewhere. I'd check the 12V fuse panel and see any are blown.

[@truker1970]

@@LoveYourRV All fuses in panel are good. Is there a 12 volt feed from the furnace? Saw on another site there is another breaker in the furnace.

[@LoveYourRV]

There is a 12V feed to the thermostat from the main RV 12V distribution circuits to trigger the AC and its fans on and off and the furnace run cycle on and off. This 12V is switched via relays in the Honeywell thermostat which is powered by the AA batteries. I assume the AC and furnace control boards also have relays. Then there is a 12V feed from the main 12V RV distribution right to the furnace to run its fan and gas igniter and power the control board.

[@truker1970]

@@LoveYourRV Thank you for the help. It's strange that there is 1 volt at the thermostat. I would think it's all or none which leads me to believe that maybe I cooked a control board somewhere. I'll keep working on it this weekend at the lake. Thanks again.

[@JanFMiller]

Thanks a million! I was wanting to do the exact same thing, and your article answered all my questions and saved me a lot of time! Grand!!!!

[@LoveYourRV]

Great to hear!

[@toddramsay977]

Nice video Ray! Well done!

[@jenniferwatson1949]

What if we don’t want to automatically change over to the AC. We mostly boondock, so won’t have the power to run the AC. Wouldn’t want to run down battery or ruin the AC because it’s “trying to start the AC”.

[@LoveYourRV]

You still have the option to set it for heating only or cooling only or auto mode. Usually what I do is once summer is over and I no longer need to use the air conditioner much at all is to flip off the breaker labeled for the AC on the RV power panel so it gets no AC power at all. So then even if my accident the thermostat tries to switch the AC on nothing happens. It won't ruin the AC. Cheers, Ray

[@jenniferwatson1949]

@@LoveYourRV Thanks. Good video(s) for this. I have watched now a few of your vids.

[@AlM-tz8yx]

Thanks for making the video. I really wish you would have shown how the wires go into the new thermostat. It's a very important step to skip it seems at least it is with me. So much great detail in every other part of your video, you even say to leave the jumper in but nothing on wiring the replacement thermostat.

[@LoveYourRV]

Likely because this was just an update video for two other videos on thermostats I did for my viewers, sorry you came in late - www.loveyourrv.com/rv-thermostat-upgrade-honeywell-focuspro-5000/ and earlier www.loveyourrv.com/hunter-42999b-digital-rv-thermostat-install/ It does say in the title Mod "Explained" and previous links are in description Cheers, Ray

[@AlM-tz8yx]

@@LoveYourRV Sounds like that is just what I needed, thank you. this video is so detailed that I didn't think to look for another one. I couldn't figure out how someone as detailed as you would leave it out. My old thermostat is not labeled by color on the terminals, it has the words furnace (fur), cool, hi fan, etc.. My new one just says G, Y, W, O/B, R and RC (jumped) .... so it wasn't clear and I didn't want to guess. Thanks again. EDIT: I just looked at your first link and it's exactly what I needed.... perfect! I'm not using the Honeywell, I'm using an Orbit 83521 because it's programable for 7 days. I use my Travel Trailer as a home office.

[@WildDigger]

So you don't need to use the blue wire? I hooked up my blue do I need to remove it? Other than that I just kept mine at high fan. Thanks. Matt.

[@LoveYourRV]

Things can vary from RV to RV but for my wiring the blue wasn't no longer needed. Since the new thermostat control chips and relays are is powered by alkaline batteries and not the RV 12V system it doesn't need the blue -12 wire hookup like the OEM Coleman Mach thermostat does.

[@dan8220]

I have a forest river vibe and from what I’m told the newer air system. I absolutely hate it. It’s a 3 wire system that has auto high low settings, thing is that the only time it will cycle on and off is in auto mode and that will also switch back and forth from low to high speeds automatically. If you trying to watch tv it is very annoying to keep hearing it change from low to high speeds. The fan stops the compressor stays running then the fan speed changes. Other option is to select low or high and not auto but in that setting it is always running no cycle off mode.

[@LoveYourRV]

That would be annoying, bad enough how loud the AC is to start with. I tell you the people who design these rigs must never camp in them.

[@dan8220]

@@LoveYourRV Hey Ray, the RTH5100B is also now discontinued, do you think Honeywell TH5110D1006 would be a good replacement?

[@LoveYourRV]

@@dan8220 Looks to me like it should work. The main thing is to have the onboard batteries. They power the switching in loo of having the usual house 24VAC power line. I can see on this photo m.media-amazon.com/images/I/51LbL7bukVL._AC_SL1298_.jpg it says C is optional with the batteries, so that is what you need to see.

[@dan8220]

@@LoveYourRV 10-4 I think it's good also, I put this one in my forest river and used 2 aa batteries to power it. Now I have a Jayco and upgrading from the same Coleman Mach like yours so all is identical but the thermostat is no longer made, so the next best is the 5110. C would be the blue wire that is not needed on this application. Thank You.

[@tisch006]

I have the exact same set-up. I'd love to have a wifi thermostat. If a can find a wifi residential thermostat that works of batteries, I don't see why that wouldn't work also?

[@LoveYourRV]

I imagine a person could install a power converter in the RV to supply the 24 VAC that most home thermostats use. Could run an inverter then use the 110VAC to power a 110VAC to 24VAC step down transformer or use a 12VDC to 24VAC converter. Something like this www.powerstream.com/inv-12dc-24vac.htm

[@greggardiner8779]

Ray, I have been wanting to install a thermostat like this one. My issue is my system is run by a remote control so there are no wires to connect to a thermostat. The crazy remote control dies at the most inconvenient times. Great tutorial though.

[@LoveYourRV]

Oh, ya that would be a pain. :(

[@randytorboli]

Would a Aprilaire model 8444 thermostat also work in a RV Because it's the same as a Honeywell thermostat and it also has the auto change over

[@LoveYourRV]

If it can run on batteries it should work. The reason most don't work is they as looking for 24V AC for power that RVs don't have. Some people will install a voltage converter so they will work off the 12V DC in the RV but easier to find a thermostat like the Honeywell I used that can run off its own batteries. Cheers, Ray

[@randytorboli]

@@LoveYourRV cool because a friend of mine actually has an RV and he's not happy with the thermostat that came in it and wanted to upgrade it and didn't know if a residential thermostat like a Honeywell or Aprilaire would work

[@BenjaminHansen]

Ray, do you have a off position in the ON/ON switch that you installed for the fan? If so and it's placed in the off position what will happen to the compressor as th ac is running?

[@LoveYourRV]

No, the switch I installed is for high or low fan speed. The thermostat has a fan button for on all the time or auto mode where the fan comes on when the compressor runs and shut off when the compressor shuts off.

[@joshuadowdle6033]

My Coleman thermostat shorted our and would only turn the fan on. I swapped it out using your instructions and it seems to work expect that the compressor will not come on. I have replaced the capacitors but it did not help. Any ideas besides taking it in? Thanks for the great how to video.

[@LoveYourRV]

There is a small control board located at the front of the AC unit, it's got a few relays and resistors, etc on it. I don't think there is a fuse there, but could be wrong. You can see it in this video clip - kzbin.info/www/bejne/nKeYfHWemaqphMk from this blog post - www.loveyourrv.com/rv-air-conditioner-maintenance-tips/ Maybe you can find the service manual for your model online and troubleshoot. Cheers, Ray

[@Eightball2516]

I have 2 thermostats in my traile one for heat one for cool does this work for both

[@LoveYourRV]

Yes, for my trailer with Coleman Mach 3 AC and Suburban SF30 furnace this Honeywell digital auto switches from heating to cooling which is nice as we often need both in a single day at certain times of the year. There are a wide range of appliances and wiring in RVs so can't guarantee it would work for you. Cheers, Ray

[@pedalpower4832]

How did you connect the wires to the micro switch? Solder or use a connector?

[@LoveYourRV]

I soldered them

[@williamfry6087]

Brilliant Ray, Thanks

[@Bobherry]

I AM A HVAC TECH! Any Honeywell thermostat whenever it flashes Cool On or Heat On that means it is in a timeout. Some of them have a programming option to change how long it lasts from 0 mins to 5 mins.

[@LoveYourRV]

Thanks for the info. The Honeywell we have seems to be set for about 2 - 3 minutes. Cheers, Ray

[@davidcrawford6505]

I'd like to move my thermostat. It's right above the fireplace in my 2020 26bh Vibe. Poor location.

[@bmack2076]

I would like to install a Honeywell digital thermostat upgrade but have a concern that the maximum is "1 amp." My furnace runs slightly over at ~1.05 -1.10 amps. Will/could this lead to premature failure of the thermostat or worse....?

[@LoveYourRV]

Personally, I wouldn't be concerned about that small of difference on a low voltage circuit and ratings usually have a bit of wiggle room.

[@bmack2076]

@@LoveYourRV Thanks... appreciate the response. Keep doing the RV videos for those of use that are 'land locked' and trailering. Cheers

[@LoveYourRV]

You bet, another month or so of boating left then back in the RV for 8 months. :)

[@toddkelley7073]

Installed Honeywell thermostat in my RV works fine but when my heat comes on so does the fan on my a/c. I decided not to go with high/low toggle so just hooked hi fan directly to thermostat, any suggestions on how to fix this?

[@toddkelley7073]

Nevermind, I fixed it. My thermostat was set for electric heat, changed to gas, working as it should now. Thanks for video

[@LoveYourRV]

Thanks for the follow-up. Likely will help others with the same issue. Cheers, Ray

[@masonpugh3637]

my coleman-mach will not turn on until it hits 85 for the heat so my brother sent me an rth 2300 programmable thermostat is there a difference

[@LoveYourRV]

Shouldn't be much difference unless the Coleman Mach is broken.

[@honraigoldstein5702]

Very educational. Thanks.

[@dogpatch75]

I have been considering changing out our thermostat. An advantage of a good digital thermostat is its ability to be control the furnace to lower temps. Our Advent analog thermostat (2014) cannot be set below 60° which causes excessive propane consumption and a rig that is too hot for comfortable sleeping in cold weather. My first thought was that the factory just used the cheapest thermostat they could get. But since learning that our heating system has a vent that provides heated air to the underbelly, I suspect this design may be intended to prevent frozen plumbing. I wonder if installation of a digital thermostat would increase the risk of underbelly freezing if set too low. Ray, do you have any experience or thoughts on this?

[@LoveYourRV]

Sorry, I don't have too much experience with cold-weather camping and my wife likes it warm at night so the furnace is usually running above 60. Maybe the cheap analog is limited to a low of 60 because of the way it functions. Usually they are using a simple bimetal strip or spring to regulate. Maybe the properties of the metal don't allow for a lower setting. Just a thought. Cheers, Ray

[@randytorboli]

I know on the heat only thermostat their is an off switch which on some thermostats it's on the bottom of it and on others it's built into the temperature selector lever

[@JMHDKDKL22]

Curious as to why you didn't install a digital thermostat that has the dual fan speed setting?

[@LoveYourRV]

Back then, I didn't see one that would run off its own onboard batteries and have dual speed fan option. Maybe they have them now. Generally though, I rarely run my AC fan in high speed anyway.

[@gibsonrocker17]

My Coleman Mach thermostat is intermittently malfunctioning and keeping the furnace on, so I'm looking to upgrade to a digital unit. Have you had any issues with this one after the install? I know a lot of folks post initial reviews or videos, but you never hear about any long-term updates. Is it still working well for you without any issue at this point?

[@LoveYourRV]

I've had a couple updates I've posted on this on this. Here was my most recent a couple months ago - kzbin.info/www/bejne/kKnYnnp9h7-jjKM Cheers, Ray

[@gibsonrocker17]

@@LoveYourRV Awesome! Just watched your update. That's helpful to know how long it's been working without any issue. My current Coleman Mach analog thermostat (same one you featured in your videos) has malfunctioned 4 times over the past couple years and kept the heat running continuously. It did it once last year and 3 times this year, so I'm getting to the point where I'm feeling like making the jump to a digital one. Thankfully, your wiring is similar to mine, so I'd feel more comfortable doing the upgrade when I'm ready. I wish I could pinpoint what's causing this one to malfunction, but maybe something's up with the relay or one of the resistors, but that'd be really hard to track down and I'm not much of an electrical whiz either haha. Thanks!

[@chuckshapley1997]

I did this upgrade but it will only work the AC heater won’t fire.

[@TheBuddy1939]

Great upgrade and informative.

[@EvilEye1986]

Will this work if my little slider thermostat only controls my heater?

[@LoveYourRV]

Hard to know, there is a lot of different wiring out there in RV heaters. Best bet is to try and located the manual with the wiring diagram for your make and model of thermostat and furnace and might be able to figure it out from there.

[@georgecmaugeriidawargames5373]

Hello I've got a question that perhaps you could possibly help me with. I've got an Atwood heater in my RV, 1997,

[@LoveYourRV]

Sorry I'm not familiar with the Atwood furnaces and that is an oldie, the one I have is a 2010 Suburban. If you can locate a model number you may be able to Google it and hopefully find a Service Manual to download and in that locate a wiring diagram for the thermostat. Once you have that you can determine what the wires are. Color coding isn't always the same between different manufactures and RV makers. The other option is to locate the manual for the old thermostat. Cheers, Ray

[@kevinj8258]

Looks like you can run a 24V thermostat on a 12V system like your RV. Do you think that maybe this is why it failed previous? Like the idea but still wondering how long this will last.- there is a fuse internal to the old manual Coleman Mach thermostat so wondering why? Voltage spikes or other overload danger on the thermostat ?

[@LoveYourRV]

I had a Hunter thermostat running off the 2 AA batteries for 3 years without a problem, only changed to the Honeywell to get the auto cooling/heating switch over. If you do a search you'll find lots of people have done this mod with no problems, think it was a dud thermostat and in this day and age of cheap quality its not all the surprising. :)

[@kevinj8258]

Love Your RV - okay you convinced me to give it a try and install one.

[@LoveYourRV]

@@kevinj8258 :) I bought another Honeywell a few months ago and its been working fine. Cheers, Ray

[@kevinj8258]

Ordered one from amazon. Assume I can use just high speed fan and not use low speed at all? Don’t care about low speed.

[@LoveYourRV]

Yes

[@MacRides1]

Great video Ray - did you ever consider installing a WiFi thermostat so you could turn it up or down when you are away from the rig ? It would require some sort of WiFi hotspot when you are away. The Sensi wifi thermostat is also powered by 2 AA batteries and does not require a 24v power. I have these at home and I can say without the 24v power it does use batteries faster. I upgraded my home unit and the new one has 24v - in that case it uses the batteries only as a backup .

[@LoveYourRV]

Isn't really something I find we need that bad. A guess a person could install a 12VDC to 24VAC DC/AC Inverter then use any of the WiFi thermostats or more elaborate programmable thermostats, but this simple one serves our needs. Cheers, Ray

[@commonsense2469]

Great video!

[@justme4172]

What did you do with the gray wire?

[@LoveYourRV]

Gray is one of the fan speed wires. Gray and Green for high and low. So I attached it to my fan speed switch kzbin.info/www/bejne/nKurZKmKj8pmh8U

[@justme4172]

@@LoveYourRV Same for blue also?

[@LoveYourRV]

On my thermostat install for a Suburban furnace and Coleman Mach 3 AC in a 2011 Keystone Cougar the blue is a negative ground wire for powering the old thermostat circuitry but the new digital thermostat gets power for that from its onboard alkaline batteries so the blue wire isn't needed anymore.

[@CPUDOCTHE1]

I have a Dometic digital thermostat in my Jayco. I am wanting to upgrade to an analog thermostat that works. Would the installation be the reverse of what you show? I bought it in February. Last night when I went into the camper it was 73 degrees and the thermostat was set to 72 and the AC was not running. The front bedroom was much hotter. I moved the thermostat to 71 degrees. Still no AC running. I set it back to 72 and turned the fan to high to hopefully equalize the temperature and went to sleep. Several hours later I woke up and it was 67.5 degrees in the camper with the AC running full blast. This morning it was 65 degrees in the camper before I turned the AC off. I later turned it back on and it appeared to run correctly. When I returned to the camper about 4 pm this after noon, the AC was running and it was 84 degrees in the camper. WTF(Why This not Functioning)?

[@LoveYourRV]

I'm not familiar with Dometic air conditioners and thermostats. Thermostats have changed over the years. Some use a newer CANbus digital wiring system which is quite different than what I showed here for my old Coleman Mach AC. Maybe if you provided the model number of the AC or thermostat I could look up the manual and see how it is wired. Cheers, Ray

[@timf6916]

Nice video, good information

[@JazerNorth]

Take your time wiring ... I, umm, fried my board on one install. So ... careful careful careful. :) It isn't hard, if you really pay attention... which, um, I didn't.

[@wilkbilt]

what are the dimensions of this unit?

[@LoveYourRV]

Product Size (WxDxH): 4.5 x .75 x 3.5 in. www.honeywellstore.com/store/products/honeywell-rth5100b-deluxe-non-programmable-thermostat.htm

[@natesjeep]

Video just drags on and on. Get to the point already

[@LoveYourRV]

There is no specific point. The title of the video says *Explained* I can't magically know exactly what you specifically need to know and put it at the front of the video. Chill out, dude.