Electric Heat Strip?

[TheGuy]

I'm kind of shocked, but I got an email saying the parts on the truck for delivery today. We have an RV show this weekend, so that'll take my day on Saturday, but maybe I'll get to it Sunday. It would be nice to get this out of the way.

The only thing I'm wondering about is that it looks like the bolts holding the control board in place are done from the back side. If so, I may have to remove the shroud to do this. Not sure how bad that'll be. I'm trying to avoid voiding my warranties.

[BigSwick]

Looking at ebay only, you can get a 15K btu heat pump and thermostat for $1200-1500. Anybody go this route for some feedback? thanks.

[TheGuy]

Looking at ebay only, you can get a 15K btu heat pump and thermostat for $1200-1500. Anybody go this route for some feedback? thanks.

Oof.. too rich for my blood.

Sent from my SM-G892A using Tapatalk

[TheGuy]

Disclaimer: I'm not an expert on any of this. This is my experience working on my particular camper. If you choose to try this and something goes wrong, I cannot be held liable.

Okay, so it's time for an update!



DISCONNECT ALL 120v & 12V POWER! I know it kinda goes with out saying, but you want to disconnect all the power. I also disconnected the 12V because the thermostat doesn't turn off when you cut the 120V. This let's it run the furnace on the battery. I had to think about that one for a minute, but you're probably smarter than me.

I got the parts right away from RVUpgrades.com and promptly left them on the dining room table for a few weeks until both pleasant weather and my motivation collided. The details are a little spotty as I forgot to document some things along the way, but this should get you in the ballpark...

I installed both the heater strip and the controller box from the roof by first removing the 4 bolts holding the outer black cover onto the unit. Then, from the front of the unit, I lifted the front edge over some sheet metal tabs designed to hold it down. I rocked it back and forth to get the cover completely removed. I had to remove about a dozen sheet metal screws from the front nose that keeps that panel in place. Some were covered with foil tape which I had on hand so I replaced it during reassembly. If you're careful, you may not damage it. Once you get that front panel off you can easily see the control box held on with two screws and where the heat strip will mount.

• Left: Old Control Box
• Middle: Brown Wire - will carry the 'heat' signal
• Right (bottom): Heat Strip Mounting Flange

I removed the old box and replaced it with the new one being careful to make sure all the signal wires were connected to the corresponding terminals on the new box.



The old control box from inside. The new one is metal and has a 'W' terminal that this one lacks. Otherwise, they're mechanically identical.


I then crimped a new blade connector on the existing & unconnected brown wire. This will be the "heat pump" signal to the unit. That was then hooked to the 'W' terminal on the new control box. I reused the existing wire junctions to tie the control box into the 120V system.

The heat strip itself just attaches with an allen head pinch bolt to the flange in front of the evaporator coil and plugs into the side of the control box.

To wrap up the top-side work: Make sure all the wires are clear of any sharp edges and the heat strip, replace the metal panel, and replace the outer cover following the ubiquitous Haynes manual instruction... "Installation is reverse of removal."



This is the old thermostat. The new wire will go between the Orange 'W' (furnace) wire and the Yellow 'Y' (Compressor) wire. On the new thermostat (not-pictured), it will be labeled WHP.

I then moved inside and installed the new thermostat by moving one wire at a time and referencing a picture taken beforehand where needed. (Tip: The connectors on the thermostat hold very tightly. I used some channel locks to press them which releases the wires.) The only wiring difference between the two thermostats is the new wire on the WHP terminal. I used a butt connector to add a pigtail on that end of the brown wire as it was too short to reach my thermostat and then landed that final connection.

Once done, I compared pics of the thermostat to pics of the control box (Tip: The control box connections are visible from inside with air filters removed from the ceiling kit). Then I reconnected power and fired it up. I cycled through all modes and everything seemed to work. It was warm that day so, it was hard to tell if the strip was really doing anything, so I used an instant read thermometer to verify that the strip was indeed heating. I was a little disappointed that I couldn't really tell by feel, though. On the plus side, nothing caught fire... So, I call that a win.

We took a trip last weekend and it got kinda chilly with a low of 56F Saturday night. When we came in for dinner the strip warmed the camper up about 4 degrees with no trouble. As I expected, the air was warmer than the surrounding air, but not hot. It's basically the equivalent of a small space heater or a large hair dryer. At any rate, it was able to control the temperature of the camper all night using the park's electricity instead of my propane. I figure in 20 years or so, I might have saved enough propane to pay for all this!

After some playing around I eventually learned (from the instructions) that when you're in electric heat mode, the thermostat will call for the furnace if the ambient temp falls more than 5 degrees below the set-point. After the third strike, the electric heat is "locked out" for 1h 45m. The 3-strike counter is reset when the electric heat runs for 20 minutes without crossing that threshold and requiring furnace backup. It's not really a major deal, but I didn't realize it would work this way. It's nice to know that if we go to sleep on electric heat and it gets too cold for it to keep up, the furnace will kick in without me having to do anything.

As I mentioned before, the parts I ordered were:
Strip: 9233A4551
Thermostat: 9630-3361
Control Box: 8330-5571 or 9330C755*

That about wraps it up. I'll try to get some better pictures later, but for now this project is done. I hope it helps someone.

[tfbriels]

I just wanted you to know how much I appreciated this helpful post. I just completed the install of two heat strips on my RV and I would have been lost without your excellent commentary. My unit was only slightly different (2019 model Coleman Mach 11,000 BTU) and thankfully I did not need to go up on the roof. I did the first install in about an hour and the second one in 15 minutes. Works like a champ! It takes some time for the heat strip to put out warm air but once it gets cranking it really does the job, much better than expected. They are power hogs, however, drawing about 16 amps each in operation. Again, thank you for your efforts. Much appreciated!

[TheGuy]

I just wanted you to know how much I appreciated this helpful post. I just completed the install of two heat strips on my RV and I would have been lost without your excellent commentary. My unit was only slightly different (2019 model Coleman Mach 11,000 BTU) and thankfully I did not need to go up on the roof. I did the first install in about an hour and the second one in 15 minutes. Works like a champ! It takes some time for the heat strip to put out warm air but once it gets cranking it really does the job, much better than expected. They are power hogs, however, drawing about 16 amps each in operation. Again, thank you for your efforts. Much appreciated!

Glad I could help!

[The_Lovells]

FWIW. I recently installed the above three components to both the front and rear AC units on our 297RSTS. After spending five nights camping, I can say that they definitely work. When we arrived at the campground the RV internal temp was 43 degrees. I turned on the electric fireplace and set it to 74 degrees, I turned both units to electric heat via their thermostats, and set them to 72 degrees, the living area unit figured out that the temperature could not be made up via electric heat and turned the furnace on. The bedroom unit does not connect to the furnace and will never be anything but electric heat. The RV was quickly at the expected temperatures and remained so. With temperatures dropping to 26 degrees at night I was expecting the furnace to run to keep up, it did not. the two heat strips and the electric fireplace easily kept up. In fact the bedroom got too hot, as the living room heat strip, fireplace and two humans effectively heated it as well. I was concerned about the underbody piping and tanks, tank heaters were on, so that added slightly to the underbelly heat that was not getting any furnace air. Despite the very cold water from the fresh water tank (no water at the Cedar Point National Forest sites), we experienced a warm and comfortable camping trip. I would probably not rely on this setup for lower temperatures over concern about the underbelly temperatures, but was very happy with the results. We are off to the Outer Banks later this month and expect slightly warmer overnight temps. I will update when we get back.

[TheGuy]

FWIW. I recently installed the above three components to both the front and rear AC units on our 297RSTS. After spending five nights camping, I can say that they definitely work. When we arrived at the campground the RV internal temp was 43 degrees. I turned on the electric fireplace and set it to 74 degrees, I turned both units to electric heat via their thermostats, and set them to 72 degrees, the living area unit figured out that the temperature could not be made up via electric heat and turned the furnace on. The bedroom unit does not connect to the furnace and will never be anything but electric heat. The RV was quickly at the expected temperatures and remained so. With temperatures dropping to 26 degrees at night I was expecting the furnace to run to keep up, it did not. the two heat strips and the electric fireplace easily kept up. In fact the bedroom got too hot, as the living room heat strip, fireplace and two humans effectively heated it as well. I was concerned about the underbody piping and tanks, tank heaters were on, so that added slightly to the underbelly heat that was not getting any furnace air. Despite the very cold water from the fresh water tank (no water at the Cedar Point National Forest sites), we experienced a warm and comfortable camping trip. I would probably not rely on this setup for lower temperatures over concern about the underbelly temperatures, but was very happy with the results. We are off to the Outer Banks later this month and expect slightly warmer overnight temps. I will update when we get back.

Glad it worked out for you. My sister's family stayed in ours for Christmas and we had similar results. They got too hot so the furnace did cycle a bit, I think. It got to 26 on my weather station about 60' away. So it was cold (for NEFL)! We haven't had temps like that here in a while.

We ran it on a 20A circuit too. I couldn't be happier.

Cheers

Sent from my SM-G892A using Tapatalk

[Heavysledz]

I did this same setup on my Alpenlite truck camper. Since the AC unit on the camper has ceiling controls (not tied to thermostat for furnace), all I had to buy was the heat strip which at the time I found online for $23. It was literally plug-and-play and took all of 10 minutes to install and change out the supplied control knob. The camper is not 4-seasons rated so it is lacking in the insulation department and it still put out enough heat to keep the camper at 72' degrees for the duration of our 4-day trip. It was in the 40's during the day and in the low 20's at night. Granted, this is a much smaller space to heat but the fact that it is not nearly as insulted as our Imagine TT, I am confident that it will provide us enough heating when combined with the fireplace to heat our 2250RK and save us some money on propane.

So to anyone on the fence about this mod, as long as your expectations are that this is not a permanent replacement for your gas furnace but an augmented heat source designed to "take the chill off", you will not be disappointed. With that said, if you have a fire place, then you are likely going to be able to heat your unit 90%+ of the time on electric vs gas. In a smaller unit like my Imagine 2250RK (awaiting delivery ) I suspect this will perform very well based on past experience.

[RichAP]

I am trying to install the heat strip in my Momentum 395MS.

The difference for me is I have OneControl and no physical thermostats.

From reading the thread, it seems like I will need to connect a wire to both the AC control box(W terminal) and then also on the main Lippert One Control board.

As far as the thermostats are concerned, is a heat strip and a heat pump the same thing, same signaling from the thermostat to control box?