Are electric appliances watt limited?

LuvWildlife · 03-12-2019, 09:43 PM

Hello, we recently sold our larger diesel RV and downsized again to a Winnebago Fuse....not having an oven or convection microwave I purchased a 1200w pizza cooker that browns. I figured it’d be cheaper than an inverter or oven

Question, is 1200watts too high to use when hooked up to shore power?
What wattage is tops for you to use? Anyone have problems?

Thanks, I promised my husband to return it if it’s too risky for blowing fuses.

or I might buy a 1400 watt toaster oven instead, if the rig can take the load. I couldn’t find anything with less other than a bbq stone pan or similar.

al1florida · 03-13-2019, 08:03 AM

Assuming your rig is set up for 30amp service you have a max of about 3600 watts. To stay on the side of caution it is best to limit your power usage to about 3000 watts total.

So 1200 watts would not be a problem.

You do need to be careful though. Don't run more than 2 high power devices at the same time. That is, if you are running the air conditioner, you can run the 1200 watt device, but be sure that the water heater is not set to heat w/elect or make sure you don't run a coffee pot, or microwave at the same time.

BobC · 03-13-2019, 09:50 AM

Also, if you need to run a portable device in addition to your A/C or other high wattage appliance, you can always plug into the campground's supplemental 15A shore power outlet as long as you use a heavy duty extension cord.

LuvWildlife · 03-13-2019, 12:32 PM

Thanks for the info! I see Irv2 has a few posts about the amps. But I wasn’t sure about the smaller RVs.

I hope it works for pizza or cookies, crisping, etc. I will post a thumbs up if the browner/cooker works ok.

WinnieView · 03-13-2019, 02:11 PM

What you might need to consider is that in many RVs such as our class C, Winnebago has installed a power share switch. It 'cuts off' the hot water heater if the microwave and AC are both on to reduce overall current draw.
So if you are using the new appliance in place of the microwave plugged into the same outlet it may come into play. Otherwise it may be unknown what the
current draw is, without measuring it at the time.

Many owners replace their factory microwave with a similar oven.

P.S. It would probably also be a good idea to consult the Wiring Diagrams for your Winnebago year and model found here;

Winnebago Industries

neub · 03-13-2019, 02:21 PM

Yes you do need to look at amps in particular what the individual circuit breaker that feeds the line/plug that you are using. Yes while you do have a 30 amp coach those amps are divided into different circuits within your breaker box therefore you most likely do not have 30 amps available at any plug. Check your breakers amp rating and what that breaker feeds and you will then know how much that line/plug can handle I am guessing your ac plugs along the wall are probably on 15 amp circuit breakers. So if you have a 15 amp circuit breaker on a particular line then the most you can run on that line is 1800 watts (120 volts × 15 amps). Those 1800 watts would be the total max you could run on that line so if you had a 1500 watt heater on and then also turned on you electric coffee maker i.e. 800 watts you would blow the circuit breaker

powercat_ras · 03-13-2019, 02:50 PM

Generally single loads designed to run on a 15 amp residential circuit breaker protected circuit will have a maximum continuous worst case draw of about 1500 Watts at any voltage between 108 volts and 132 volts ( 90% to 110 % of the "normal" voltage of 120 volts ). The worst case amps for a single load is typically 13.9 amps. Anything that is sold for residential use that has a standard 3 prong plug must draw less than 15 amps, and should work in your RV when you are on shore power.

Only "gotcha" is that RV makers use outlets made to go into thin walls that make punchdown connections to the electrical wire and if not punched down correctly when the RV is made, they punchdown connections won't take the current and will overheat , damaging the outlet and the electrical wire and eventually failing. You can check for heat at the outlet you plug your heavy load into and other outlets on the same circuit that might be between the heavy load outlet and the electrical breaker box. If any outlet is more than slightly warm to the touch, RED FLAG, you need to have the RV serviced to check the wire punchdowns for correctness and perhaps replace any outlets that are already heat damaged.

LuvWildlife · 03-13-2019, 03:25 PM

Thank you Minnieview, Neuhaus and Randy as well. Great safety info and checkpoints, very appreciated. I’m trying to figure out now why this Particular Fuse doesn’t have a convection oven when most that we looked at did. I guess this was the stripped model and that was why it was marked down in price. We may upgrade.

powercat_ras · 03-13-2019, 04:05 PM

The HiPointe Microwave/Convection Oven that Winnebago uses in many lower cost product lines is terrible, IMHO you are lucky not to have it. It has it microwave output port in a location that does not evenly distribute the microwaves thruout the cooking chamber making cook times longer and creating cool spots and hot spots. TERRIBLE. The convection oven is also hard to use, takes well over 1/2 hour to preheat to 350F and even longer to preheat to 400F, and it really heats up the RV. The exhaust fan always comes on, to keep the HiPoint from destroying itself from the heat the electric element puts out, so you lose a lot of heated air when its cool and a lot of cooled air when its hot. Same issue for me you had to figure out temps and cooking times by trial and error as it just did not cook the same as a residential oven or for that matter a high quality countertop convection oven.

I tore it out of my Vista and replaced it with a LG residential microwave I bought at a Home Center on sale for $ 165. I do have an Atwood LP oven under my stove and use it to bake, once I figured it out. Putting a pizza stone between the burner and the backing rack finally did the trick to get it to cook reasonably similar to a residential oven.

LuvWildlife · 03-14-2019, 11:55 PM

Thanks Randy. The little pizza oven I bought I tried at home. It suffices for browning and baking a few things, but it’s not the end all answer either. Made by Cucina, it can only be turned off by unplugging it, lol.

But good for browning/cooking tortillas, toasting, grilling, bisquits, cookies, hot dogs, etc. it will do, we don’t cook much. I will miss my oven from the Tiffin. It worked pretty well, taking a bit longer to cook. Make sure it’s fully heated, it took like 15 min., that helps.

Thanks again everyone, for the links to ‘wiring’ too.