What effect does an electric heater have?

Agree you just have to be smart. Always turn off the polonis heater when using the microwave. Simple, easy and everything works as it should.

Here is a Volt/Amp/Watt Converter.

900 watt = 7.5 amp or 25% of 30 amp capacity
1500 watt = 12.5 amp or about 41% of 30 amp capacity

I almost always use the lower setting based on touching the plug of heater when running. Always cool on low setting. Sometimes very warm on high setting which I take as a potential higher amp draw than wiring was designed for. Not worth the risk of fire. Randu

30 amps at 120 volts is 3600 watts. So that electric heater sucks up a good chunk of your capacity. On the other hand, you are not going to be using your AC at the same time, your microwave (second biggest draw in the rig) is probably 1100 watts, so unless you insist on running heater, microwave, coffee maker (600 watts), and every light in the place (at 18 watts a pop) all at the same time, you should have no problems.

(The math is simple, add 'em up as you turn 'em on, and as long as the total is less than 3,000 watts, you got a winner. That allows room for the converter to be charging a depleted battery at the same time, over which you have no real control.)

1500 watts at 120 volts equals 12.5 amps. You will have 17.5 amps left.
Microwave = 13.0 amps
Water Heater = 12.5 amps
Refrigerator = 4 amps
Converter (general lighting) = 4 to 10 amps
You will be able to use the electric space heater and the water heater without any issue, but you will have to turn one of them off when you use the microwave.

About the only thing that bothers us is when we use the high wattage microwave and electric heater at the same time...

Also cant use the vacuum or the hair dryer at the same time the electric heater is on...

No harm - just trips breaker when it happens...

What we do alot to help is to run in a separate extension cord from the camp ground pedestal and use their 20AMP service just for the electric heaters. This will have its own circuit breaker at the CG pedestal. Have run into some CGs that didn't want you to do this but if it is there to use I will use it...

We normally run two electric heaters in our trailer with #3-#4 settings on the electric heater thermostat in lieu of the trailer propane furnace. Our propane furnace drives us crazy with all of the blower noise it makes. Its also better for us to use the CG's electric instead of our propane whenever we can.

Roy Ken

Iif you can run a hevy duty extension cord the the pedastal non.
If not you will have to do some power managemant you have to remember you only have 30amps