Adding electric heat to coleman Mach3+

[Tyandkate]

Any one ever added electric heat to there rooftop unit? curious as a option to heat up the camper a bit with out the need of gas. Just curious if anyone uses it and the results.

[myredracer]

One reason not to plug a 1500 watt heater into a standard SCD RV receptacle is that the factories don't always install them correctly and according to code. The factories don't have licensed electricians and the work is never inspected by a gov't inspector like it is in buildings. A photo below is what I found in one of our TTs and only 1/2 of the hot wires were pushed onto the "stabs" and the prong was bent to the side plus the paper wasn't removed off the ground wire. Have found this in two brands of TTs we've owned. One of the RV recepts. should be able to carry 15 amps continuously but I would not trust that they were installed correctly. And if you have a few of them on a circuit and are plugging into the last one on a run, you could have a few "problem" recept's in series, compounding things. You can't install a regular residential recept. on an outside wall though so can only replace an existing one on an inside wall or cabinetry. I've found way too many various electrical issues to never trust factory work...

Using a strip heater or the furnace with add-on electric heat is noisy and not the ideal solutions in my mind. I don't like the Cheapheat system as it's a waste of time & money and they use false and/or misleading statements IMO (but will not comment further here). A plug-in portable heater(s) is a good solution, such as a ceramic cube or oil-filled heater but these provide localized heat only and can leave another area/room uncomfortably cold. If you have an enclosed underbelly and use a plug-in heater, strip heater or even Cheapheat and not use the furnace, the floor can end up uncomfortably cold. Not much you can do except maybe wear shoes or thick socks.

If going to electric heat, if you have 30 amps, the most you can use is 1500 or maybe 2,000 watts total, or even say 2250 at the extreme to have enough room for other loads. You'll have to manually switch the heater"s) off when you want to run a coffee maker, toaster and/or hair dryer at the same time. Most TTs are not particularly well insulated, esp. in ceilings if you were to take a look up there and as a result. Electric heaters can end up running non-stop unlike in a house where heaters cycle on & off and cords can get warm/hot and same with recepts.

The ultimate solution IMO is to install some recessed fan-forced electric heaters and use wall-mounted thermostats. In our first TT (a small 20 footer) I installed a ceiling semi-recessed heater in pic below. In our current TT I installed a kickspace heater under the stove and a recessed heater in the bathroom and one in the bedroom, totalling 2,000 watts and each room/area has it's own t'stat. The problem with installing permanent heaters in an RV is finding a suitable location that provides all the required min. safety clearances. If you use a fan-forced recessed heater, you want one that has a squirrel cage blower and not a propeller blade type which are a lot noisier. The ones I used are very quiet and don't interfere with the TV. I ran all wiring 100% concealed via the ceiling, walls and cabinetry. I made my own demand controller so that when the total load gets to 30 amps, the electric heat is automatically disconnected until the total load is down again. We almost never use the furnace except early or late season when the temps are close freezing. Our TT is comfortably warm and evenly heated from front to rear. An installation like this is not for the average DIY-er tho.

If you think upgrading to 50 amps will give you more total wattage, be aware that finding a 50 amp pedestal in a CG can be difficult. Prior to the 2005 NEC code edition, only 5% of CGs had to have 50 amps and then they increased it to 20%. The majority of CGs are older and unless you can find a CG (or maybe a casino) that has voluntarily built above min. code, you will need to be able to run on 30 amps.

[gmw_photos]

Lynnmor wrote:

gmw photos wrote:


Then you'd really hate the electric resistance heaters we use in our stock tanks full of water at our horse barn.

You should install a fire suppression system, (like those required above fryers in restaurants), above the water tank so the water doesn't catch on fire. :R

Yeah, I just hate it when the water catches on fire.

EDIT: the "oil" used in oil filled heaters is most typically silicone oil, which is non-flammable

[Lynnmor]

gmw photos wrote:


Then you'd really hate the electric resistance heaters we use in our stock tanks full of water at our horse barn.

You should install a fire suppression system, (like those required above fryers in restaurants), above the water tank so the water doesn't catch on fire. :R

[gmw_photos]

Lynnmor wrote:
There is something about putting an electric resistance heating element in a tank of oil that bothers me.

Then you'd really hate the electric resistance heaters we use in our stock tanks full of water at our horse barn.

[Huntindog]

Lynnmor wrote:
There is something about putting an electric resistance heating element in a tank of oil that bothers me.

Nothing to worry about... A lot of restuaraunts
Use electric power deep fryers. They get a lot hotter than an oil filled heater that is sealed.

[Lynnmor]

There is something about putting an electric resistance heating element in a tank of oil that bothers me.

[gmw_photos]

pianotuna wrote:
....snip....


Oil filled heaters do not share that risk.....snip

.... At least one of our long term members "cheats" and puts a small fan on to blow on the oil filled units.....snip

When I am at home n the S&B in the winter, I use one of the oil filled rads in my kitchen, which is where I spend most of my time. I too cheat with a little fan. I found a small "personal fan" like you might use on your desk at work. About two and a half inches diameter. I set it on the floor aimed at the base of the oil filled rad, and some measuring with the non contact IR thermometer showed I was able to pretty much even out the heat of the radiator top to bottom, plus move a little bit of air.

[pianotuna]

The best thing to do is to "coat" the interior surface of the RV with warm air. One way to do that is to use radiant heaters--the type that glow cherry red. They heat the item they are pointed at--and that item re radiates warming the air. They are good at thawing out frozen water pipes.

The draw back to the medium wave infrared is that it can burn the item it is pointed at.

Oil filled heaters do not share that risk. However, they are slow in response and rely on convection currents to warm the interior of the RV. They are about the safest one can find. I like them best because I can turn one off when I cook electrically--and the heat from it will "coast" for a time. Then when I've finished cooking, I turn it back on. At least one of our long term members "cheats" and puts a small fan on to blow on the oil filled units.

Fan heaters warm the air but do not rely on convection. Hot spots are possible so do follow the directions carefully.

No matter what type of heater is being used--be careful!

I hope we are all staying warm in this latest cold snap.

[trail-explorer]

Second Chance wrote:
...It would be much more difficult to get heavier wiring up to the roof than doing the modifications necessary in the lower utility areas of the trailer.

The heavy wiring is already up there, since it powers the A/C unit.

Should be 12 AWG / on a 20 amp circuit.

[Huntindog]

SoundGuy wrote:

Huntindog wrote:
There are advantages to both approaches. BUt overall, long term the heat in the TT will be the same.

Incorrect. Warm air rises - a heater situated on the floor is generating heat where it's needed, warming the interior of the camper and occupants as it rises and is distributed about the camper. :B An A/C mounted heater is generating heat where it's not needed, at the ceiling, where it's trapped and there is no one to benefit from that warm air. 😞 The only rationale I see for an A/C mounted heat strip is for blowing warmed air into the bed ends of a hybrid trailer, otherwise it's a useless exercise in futility when a $20 floor situated electric heater will prove far more effective at distributing warmed air where it's needed.

Do you EVER agree with anyone?

Back to what I said, I will now explain in greater detail.
5K btu is 5K btu. This is a fact.

If you run a portable 5K heater in a TT for 24 hours straight and a 5K heat strip in a TT for the same amount of time... They will BOTH stabilize at the same temps. (identical TTs and conditions)
But most everyone won't run a portable unit 24 hours straight due to safety concerns. But a permanent install of heat strips is perfectly safe to leave running night and day, when you are sleeping or away. So if you are in a campground where the elec. is "free".. Then this is an advantage.

Don't obsess over the heat rising thing (I know it's hard but try) as that is what the fan is for. Blowing the warm air into the TT and mixing it with the cold air.

[gmw_photos]

Speaking of these little stand alone electric heaters, I've had various ones over the years that I've used for instance in my garage at home for a little added heat, and one thing I have noted about them is some have a pretty sensitive "thermostat", and others not so much.

If you want one that will maintain a fairly narrow temp range, you may have to try a few different ones, returning those that don't work the way you like.

EDIT: a couple of other things along this whole line of stand alone heaters. Two fun tools that can help you manage all this is a kill-a-watt meter to plug in and check current draw, and a non-contact IR thermometer to check for wiring/outlets/plugs getting warm. Probably not necessary tools, but fun and informative nonetheless.

[pianotuna]

clutch1 wrote:
You can buy a Lasco heater at Walmart for around $40.

Or you can buy a 1500 watt three heat settings heater from Walmart for $8.86 plus tax. They both provide the same number of btu's.

[clutch1]

You can buy a Lasco heater at Walmart for around $40.

[pianotuna]

The circulation of air from the roof top ducted units over comes any convection currents from warm air rising. The largest issue is they produce only 5118 btu's. Folks expect miracles from less heat that of a small burner on a propane stove.

I have my furnace on a different thermostat, so I can use all my various heating systems together giving me access to 23,000 btu's from electric and a further 25,000 from the furnace.

[bobndot]

My 2 cents:
Maybe some floorplans work better than others, i don't know, just a thought.

After using RV's in sub zero weather, i found the entrance door to allow a lot of cold air into the TT. That always made the closest person to the door, feel cold no matter what the heat source was.
After hanging a H.D. drape over the door, I found a ceramic cube floor heater to perform better than heat strips on the ceiling .
The TT felt warmer but I will admit after many hours of NOT opening and closing the TT door, the heat strip seemed to level things out a bit when used to maintain warmth, but it takes a lot of time in cold weather.

The dealers I have personally known over the years shy away from heat strips. The one's i have spoken to like the cube or oil filled for efficiency.


Granted, most people are using their TT in much milder temps than I did but I would think the basics are still the same. Those doors leak air . Placing the cube nearer to that door worked best for me. But the heavier cold air is going to occupy the lowest points pushing the lighter warm air to the ceiling. You notice it when you step out of the shower, your legs feel cold and face feels warm . IMO, putting the warmer air low makes better sense to me.

gmw photos , i like your idea , a dedicated line. I have done that in the past in a make shift way. Your post here offers a more secure and safe line. I like....., tnx. :C