Thermostat question

pj48009 · 01-29-2020, 06:16 AM

We have a 2019 26RBSS. The furnace never worked right since we bought it and I’ll save the frustrating story of getting it fixed under warranty. We’re in Florida for the winter and I’m paying a mobile tech to try to fix it. Yes we actually need the furnace in Florida. Lol. Anyways he told me the thermostat we have frequently fails. He told me that a household thermostat won’t work but I’ve thought I’ve seen people say they’ve done this. The thermostat isn’t the cause of our furnace issues I’m just trying to be proactive.

**creativepart** · 01-29-2020, 08:37 AM

Never heard of a thermostat failing in a TT. That’s a new one on me. I’m not sure what he’s talking about. Perhaps he’s not either?

pj48009 · 01-29-2020, 09:14 AM

Everything fails in time. Home thermostats fail frequently, especially high tech ones. I replaced two thermostats in my old pop up years ago. My question is has anyone used a household thermostat in a travel trailer? Household ones are 24 volt and travel trailers are 12 volt. Old time campers were millivolt. If anyone out there can help I would be thankful.

Morich · 01-29-2020, 09:25 AM

Your question is a good one but with many answers! Don't fully trust a tech who doesn't know home thermostats are frequently used in RV! Looking online you can find numerous
examples of it being done, They often come in the way of the self-serving blogger type and range from somewhat good but limited to the downright gross" sniffle, snort, doesn't matter" U-tuber, so you have to do a fair amount of looking to get to the right info as much of it may not fit what you want. It gets them lots of traffic and that's what they really want!
So how to sort through to find what you want? Start with what the thermostat needs to do and what thermostat you choose versus what it is replacing. Simple RV, like trailers, often have a furnace and separate AC cooling on the roof which have different fans for moving the air. So cut away from the advise on how to wire for two speed fans!
Do decide if you want to go for programmable thermostats if it is in an RV and you don't have a set schedule as it is cheaper/easier to avoid the program if it is useless anyway.
Searching out the right combo is the trick as the internet is a minefield of bad info.
I am currently in the phase of swapping info with Honeywell for my swap, so I will not throw in my personal problems as you are likely to have a different set than mine.
Good luck and be assured it can be done---just walk carefully around those minefields!

pj48009 · 01-29-2020, 09:38 AM

Thank you for the thoughtful response. I don’t have an immediate need but someday may. I was thinking of a simple non programmable type. I have the roof ac and the propane furnace. There is a big temperature swing with the stock one but it’s livable. I figured a current battery operated one will work, but this mod may wait a bit. Some people have the need to talk down to you and you are not one of those people. Thanks and I’ll keep watching for useful info.

**creativepart** · 01-29-2020, 01:10 PM

Quote:

Originally Posted by pj48009

Some people have the need to talk down to you and you are not one of those people.

I sincerely hope you don't think my comment was "talking down to you" as my only intention was to save your from worry about an issue that is very rarely reported. My concern was that a repair person had made a comment that your current thermostat was some kind of ticking time bomb and would leave you stranded in the middle of the night.

Had I known what you were looking for was info about replacing your current working thermostat with a better or residential unit I too would have directed you to YouTube where there are a number of videos about that project and its challanges.

Again, sorry if my attempt to help was somehow offensive to you.

pj48009 · 01-29-2020, 02:05 PM

Omg I am so sorry. My comment was not directed at you it was a general statement. This is why I don’t like emails or texts. Much is misunderstood in words, especially if you read what I say. I am the king of using wrong words. Seriously I’m sorry.

Morich · 01-29-2020, 04:14 PM

Communications is actually getting far harder as we develop the tech to make it seem easy! Think of all the time we waste just getting a date and time set when we used just pick up the phone and get it done. It only takes a few seconds to blast out a message but it may take ten messages to find out what's up! Just life and we have to learn to ignore lots of it.
So the bigger issue is how to get to the right info n changing out the thermostat. And that seems to be much harder than I expected as on my simple standalone gas fired furnace with no heat pump and rooftop air. The only parts they share are the RV power and the thermostat, while almost all the advise I'm finding involves several points that don't apply.
The latest issue seems to be that the folks at Honeywell have a far different RV in mind than what I described. They tell me NO honeywell stat will do the job because of the variable fan speeds on an RV furnace.
NEWS to me, huh?
They blew right by the point where I mentioned it is a single speed fan!~

pj48009 · 01-29-2020, 04:33 PM

Maybe I’ll just leave well enough alone and deal with replacing the stat if it ever breaks.

Goodspike · 01-30-2020, 09:13 AM

Quote:

Originally Posted by pj48009

Everything fails in time. Home thermostats fail frequently, especially high tech ones.

Nest at one time (maybe still) was using a poor design that was prone to failure. I don't recall the details of the technology, but I don't recommend that brand for other reasons. For one thing their claims of energy savings are based on the assumption that people are too stupid to program thermostats. The only way a smart thermostat will save you any energy is if you can remotely delay the furnace coming on when it doesn't need to come on. Other than that the heat will escape your house just as quickly with or without a smart thermostat.

Morich · 01-30-2020, 11:11 AM

If one operates on a loose schedule where the time we get home may vary several hours, the smart thermostat can be used to increase the savings quite a bit over a programmable one.
Thinking of times when one might be caught at the last minute and have to stay at work several more hours. If the program increases the heat during those hours you are not there, it can be saved if one only increased the heat at the time he actually left work.

Goodspike · 01-30-2020, 11:24 AM

Quote:

Originally Posted by Morich

If one operates on a loose schedule where the time we get home may vary several hours, the smart thermostat can be used to increase the savings quite a bit over a programmable one.
Thinking of times when one might be caught at the last minute and have to stay at work several more hours. If the program increases the heat during those hours you are not there, it can be saved if one only increased the heat at the time he actually left work.

I think that's what I said when I mentioned delaying it coming on. Other than that, smart thermostats do nothing, but that is not the claim made by the manufacturer.

Morich · 01-31-2020, 09:15 AM

Some good info for the folks who want to do this mod? I finally found what I feel is a good vid of doing this as the fellow has his act together on several points and demonstrates how the Honeywell he has chosen does use only the onboard batteries to power the unit itself and simply switches the 12VDC from the RV as it passes through the thermostat relays.
Put the batteries in, turn the heat up and hear the relay click after a short pause! One way to know it works on the batteries as you've not wired it yet!

https://www.youtube.com/watch?v=fzH3vTZe3Qc

If you have two fan speeds, add a micro-switch or if you only use one of those speeds, simply leave the second speed wire off, choosing high or low speed as the one you use.