Some basic amounts of power various thing draw. Some of my numbers are a little high just to allow for a certain margin of error.
- A/C 14-18 amps. I have been successful at turning on my A/C at home on 15 amp power, but I had to do it very carefully. Turn on the fan first, let it spin up, then A/C on low. However you
cannot have anything else turned on.
- Fridge is about 5 amps.
- Electric water heater- 12 amps
- Microwave- 12 amps
- 12 volt power adapter- 3 amps on standby
- each incandescent bulb is about 1/4 amp.
- Furnace- 2 amps
So add up the cumulative amps based on power you have. If you have 15 amp power, as mentioned A/C likely won't work. I typically put my fridge into propane mode if I have 15 amp power, then keep in mind you can only use one of the water heater or microwave at any given time. And if using the either one, make sure the furnace isn't due to cut in or you don't have a dozen lights burning.
If you have 20 amp power available, you can use A/C by itself, or one of water heater or microwave without really having to worry about other things. With 30 amp service, you really don't have to worry at all about what is on with too much.
A few other quick points:
Walmart often has RV parts cheap. Like a
drinking water hose for $12
Regarding using the batteries, you have 100 amp hours in most batteries; however you don't want to drain them below 50%, so 50 amp hours. So that gives you either:
- 166 hours of fridge use on propane mode
- 12 hours of water pump use
- 33 hours of incandescent bulb use, or 350 hours of LED bulb use. (Both 921 style bulbs)
So just looking at 2 of those, if you only have 1 hour of water pump use, that brings your incandescent bulb use down to 30 hours. Have 3 bulbs running, and you are down to 10 hours. (I hope that makes sense- trying to do this quickly.)
You can also plug into your truck and run the engine to charge the battery, but you only put back 2 amps per hour. So running your truck for 4 hours only gives you 8 amps back into the battery.