Adding heat strip kit to Coleman Mach 15

[sportcoupe]

Originally Posted by sportcoupe

There was an orange at my furnace. There are orange wires everywhere. I did a continuity check of the furnace orange wire to my AC unused orange wire. It's not the same wire.

I wish Thor owners resource would give us complete 12v coach wiring diagrams.

EDIT: The orange at the furnace is the same with as the unused orange at my roof AC. This is good news as I needed an extra wire run for the new heater strip. This saves me the trouble.

My Fluke meter battery was low and I didn't catch it the first time I did a continuity test of the orange wire.

Now, awaiting parts and I will draw up my diagram for heat strip mod.

Others with their ways running electric heat are fine for others reading to get inspired. I myself an going with the invisible heat strip mod. Besides, mod is what I do

[gte534j]

thanks for posting your experience. I have considered the heating strip too but decided to just do space heaters and installed propane heater. I was considering replacing the AC with the unit that also has the heat pump option but thats expensive. The downside of having heat come out of the roof vents is that heat rises, so you might not really be heating up the RV as much as you would like. I also think the heater only puts out 800W or so, which is not much power.
Please post a status update as well when you test it when its cold.

[sportcoupe]

Originally Posted by gte534j

thanks for posting your experience. I have considered the heating strip too but decided to just do space heaters and installed propane heater. I was considering replacing the AC with the unit that also has the heat pump option but thats expensive. The downside of having heat come out of the roof vents is that heat rises, so you might not really be heating up the RV as much as you would like. I also think the heater only puts out 800W or so, which is not much power.
Please post a status update as well when you test it when its cold.

The Coleman heat strips output 5600 BTU and is rated for 120vac at 15-16 amps. That is at least 1800 watts of heat assuming a power factor of 1.

Now to be conservative, 1 BTU = 0.293 watts. The math works out to 1640 watts. Pretty close to my rated estimate.

The same format heat strip kept my Class B at 70 deg F when it was 28 deg F outside.

[sportcoupe]

Okay, I did some non-destructive system testing interrupting the BMPro multiplex units furnace output to use in a switched gas-electric heat option.

Non-destructive meaning no wires were cut.

Interrupting the BMPro furnace output for more then 30 seconds results in a fault on my touchscreen. It knows the furnace didn't light. Part of the problem is that dang orange wire that was unused at the roof AC unit. It is at the furnace and is used by the furnace and other systems. It is not just a spare wire run.

Bottom line is I will need a standalone heat only thermostat just for the electric heat strip in my roof AC unit if I pursue this mod.

I intend to continue if I find a way to get one wire to the roof AC unit.

[Judge]

Originally Posted by sportcoupe

Okay, I did some non-destructive system testing interrupting the BMPro multiplex units furnace output to use in a switched gas-electric heat option.

Non-destructive meaning no wires were cut.

Interrupting the BMPro furnace output for more then 30 seconds results in a fault on my touchscreen. It knows the furnace didn't light. Part of the problem is that dang orange wire that was unused at the roof AC unit. It is at the furnace and is used by the furnace and other systems. It is not just a spare wire run.

Bottom line is I will need a standalone heat only thermostat just for the electric heat strip in my roof AC unit if I pursue this mod.

I intend to continue if I find a way to get one wire to the roof AC unit.

I have several of these wireless switches to drain my fresh water tank and a few other upgrades. They have them for 12V and 120V applications. They work great if you just want an On / Off ability.

[ducksface]

The separate thermostat is why I didn't do the heat strip.
Fan will always be on.


I have the handiest wireless remote thermostat for our 1500w plugin heater.

https://www.amazon.com/Nashone-Wirel...ROL_THERMOSTAT

Try that.
No wires
Move thermostat wherever/whenever.

[sportcoupe]

Originally Posted by Judge

I have several of these wireless switches to drain my fresh water tank and a few other upgrades. They have them for 12V and 120V applications. They work great if you just want an On / Off ability.

A 12v wireless switch still requires wires.

I simply need to find a way to get one 20 awg wire to the roof AC unit for heat control since learning the unused orange wire is not available after todays testing.

[gte534j]

thanks for the updates on this subject. It would be nice to have an integrated heater in the AC unit with the ducting. This weekend we went camping and used our radiant oil heater:
https://www.amazon.com/DeLonghi-Comf...12688777&psc=1
Its a bit big but is quiet, puts out good heat and also serves as a quick dryer for towels/gloves/etc.

[Clowman]

I wanted to add heat strip , but it was going to be too much hassle to get everything working like I wanted .I went another route with adding a wall mount fan/convection heater . Mounted to back of dinette bench . Wired outlet inside base of the bench for power . Works great .

[sportcoupe]

I was able to access and route a new wire to the roof AC for the heat strip control box. I have to install a standalone thermostat since I have a touchscreen and it's wiring doesn't like being messed with. I tried

Overall, it will involve a little bit of wiring and three components and more expensive then a plug in heater. I gain storage space and RV room by integrating the heater into the roof ducts.

[sportcoupe]

Wired the new, dedicated heat strip thermostat today. Added a switch to have low fan all the time for circulation. Same thing I did in my Class B.

Waiting for the replacement control box due Monday.

[sportcoupe]

Setback, control box arrived with label torn off. It was advertised as NEW on eBay. Heat mode was inoperative in the control. I verified with my voltmeter. I have arranged return and sourced another new control box.

Like many RV parts, these are now hard to find in stock. Most places want double the price or they are just going to backorder for you.

[sportcoupe]

Finished today.

Received 2nd control box and bench tested before install, checked good. The 1st control box seller issued me a full refund.

Installed heat ready control box and all systems are good. The existing touchscreen works like factory. AC, fan low and high and gas furnace.

The electric 1800 watt (20 amp circuit) heat strip works off it's own thermostat. I can run electric and the gas furnace can be set to come on at the same time if it gets too cold.

I did add a manual fan low override so the fan always runs as heat strip cycles.

Pictures are the old white plastic control box (not heat ready) The all metal new control is heat ready as seen installed with heat strip unit. Next is my standard standalone thermostat mounted in bedroom. Last is my wire diagram.

[sportcoupe]

So...how does it work in real life?

This weekend we had cool weather so I tested the heat strip at home in driveway. It was 42 degs outside in the morning, 47 degs inside the rv. I turned on electric heat strip and set thermostat to 70. RV reached 70 in about 2 hours.

Slower then propane furnace for sure but it would have maintained 70 day and night once there no problem, even more if I wanted it warmer.

If it got really cold, the furnace could be set to come on as a backup.

We know spacer heaters work. This is a permanent mount space heater that takes up zero cargo room and zero setup and much less of a fire hazard. Sure it costs more but I have cargo space available for other things now and it's one less thing to deal with camping.

[Jimbo56]

Glad all works well. If you’re happy, we’re happy. Warm holiday wishes to you and yours!