Electric Space Heaters

[pdemarest]

Heading out in May to the Tetons, Yellowstone and Black Hills area and will be alternating between motels and RV parks with hook-ups. I want to carry a small space heater and most of them pull 12.5 amps when running on "High". Will the 110 volt outlets in my 2003 Premier handle that? Is there any particular outlet I should use and will I be able to simultaneously use my microwave without blowing a fuse?

Paul

[Scott]

You can draw 15 amps from an outlet without tripping the breaker. Which outlet you use isn't going to matter. Microwave is on a separate breaker, so you'll "probably" be fine running them both on a thirty amp hookup. Have fun Paul! Those are great spots.

[Blue~Go]

I want to carry a small space heater and most of them pull 12.5 amps when running on "High". Will the 110 volt outlets in my 2003 Premier handle that?

Yes they should. The outlets (with the exception of the dedicated microwave outlet) are all on one 15 amp circuit. Thus 12.5 amps should be fine. The caveat would be are you running anything else on the outlets circuit, and how many amps is/are they consuming.

Is there any particular outlet I should use and will I be able to simultaneously use my microwave without blowing a fuse?

As mentioned above, all of the AC outlets are on the same circuit, fused at 15 amps (14 gauge wire). The exception being the dedicated microwave outlet (in the dining upper cabinet in my rig), which has its own circuit and a 20 amp fuse (12 gauge wire).

So, presuming you want to keep the microwave plugged in to the microwave outlet, and presuming you have 30 amp service, then you need to add together the draw of the microwave (which is more than the "watts" it can cook with - look at the power label to check how many it draws), and the draw of the heater, plus anything else you are running, and those can't exceed 30 amps (nor can you exceed 15 amps on all of the non-microwave outlets added together).

I carry a small electric heater that is the common type you can buy at Walmart or anywhere (something like 10" x 11" x 3"), and it has three heat settings (just fan, low heat, medium heat, high heat). I find that handy for managing not just heat but also power consumption. For example high is 1500 watts, hence about 13 amps; medium is, IIRC, 1,000 watts or about 9 amps; low is 750 watts, or about 6.5 amps. I don't use the dial that acts like a thermostat, but simply turn that one all the way up and then select either low, medium, or high depending on how much heat I want or how much power I can spare.

I can't remember the exact figures for my stock microwave, but just for example if it were a "1500 watt" unit, that might mean it draws 1800 watts and outputs 1500 watts - because it's not 100% efficient (will specify on label probably on the rear). 1500 watts ÷ 115 volts would mean it would draw around 13 amps. So if that were the case, and you didn't have other large loads going, you could theoretically run microwave and heater on high on a 30 amp service. I say theoretically because I can't speak to surges, etc. You can also just turn the heater down to low.

BG

PS: Slightly off topic, but I re-purposed my microwave outlet by moving it down to the floor by the stove kick space. That way it's a dedicated electric heater outlet, with all the other outlets being on a separate circuit. So I have a theoretical 35 amps available for outlets (obvs could only use 30 tho). That's only useful if you don't want the microwave though.

[pdemarest]

Blue & Scott - thanks for the info. Last year when we went to Grand Canyon and I was concerned about our propane level we only ran the LP heater every few hours to conserve LP but it seemed to be struggling to keep up with the cold. Today I went out to the rig to check out a few things and realized that my vents were partially closed. I didn't realize that the center of the vents was actually a knob to control the size of the opening. Duh. We knew we had some items blocking the vent behind the passenger seat and moved them out of the way but still weren't getting much heat. Another mystery solved.

Meanwhile, I figure if I'm hooked up to shore power I may as well use a small space heater so I can avoid the window fogging that comes with LP heat and also to be sure I have plenty of LP for hot water and cooking (weather can be cold up there even in late Spring so although we use a portable camp stove I want to make sure I can use the inside range if needed).

Good to know the info about electrical loads.

Thanks!

[Blue~Go]

... I didn't realize that the center of the vents was actually a knob to control the size of the opening. Duh. We knew we had some items blocking the vent behind the passenger seat and moved them out of the way but still weren't getting much heat. Another mystery solved.

Yay!

Meanwhile, I figure if I'm hooked up to shore power I may as well use a small space heater

Oh absolutely. I plug in vanishingly rarely, and yet I still carry a small electric heater along. Light, inexpensive, takes up very little space -- but when I do plug in it's great to have. Plus you can do things like aim it under the sink in a cold pinch, or put it in the bathroom to avoid "meat locker" seat effect.

...so I can avoid the window fogging that comes with LP heat.../quote]

So this part I don't understand. It's true that burning propane for heat gives off moisture, BUT, 100% of that moisture should be going out through the exhaust port on the side of the rig, because the furnace is direct vented. If any (moist) combustion air is coming into the rig, that's a dangerous situation.

It may just be warm, moisture laden air (because: breathing, cooking, etc.) hitting the cold windows, but that would be the the same whether the air was heated with electricity, propane, diesel, or what have you (as long as the heater is vented, which the stock furnace is).

BG

[pdemarest]

Hi Blue - good to know about the LP heater. I assumed that it would add to the fogging because I know that cooking inside does that.

Meanwhile, more tampering leads to more issues. My original bath exhaust fan has lost most of its blades due to old age so I decided to pull it out to check the shaft size so I could order a replacement. I had already installed a new light lens but the whole mechanism seemed to shift around a lot, plus the fan generated a lot of noise. When I started to remove the inside cover (screen, frame, etc.) the plastic was literally crumbling in my hands. So, its off to the RV repair guy to install a new fan that will have the a much larger blades and diameter. During the summer we use the fan to pull hot air out of the rig while we're off boating so it will be nice to have 3 speeds.

Thanks again.

Paul

[Blue~Go]

Right, since cooking is burning fuel, and since the stove isn't directly vented to the outside, then cooking will create moisture from the fuel (plus of course steam from making pasta or whatever).

But a vented furnace won't do that, no matter how "moist" the fuel is inherently. It's still creating the moisture, but it's not coming inside.

One the vent... Funny how one project leads to another isn't it.... ahem.

The stock bathroom vent is a little flimsy. I've kept mine just because I like the way it cranks up and down quickly and the light around the perimeter is actually nice. But the minute it gives me any more trouble..... I'll likely replace it (I already replaced the lens on the light section). The fan blades on mine have also broken slightly, but I don't tend to use that fan (although maybe I would if it was a nicer fan?).