Running the heater when stopped for lunch

Is it okay when pulling over to turn on the heater? will it drain the battery in the camper or is it using the truck battery to run the fan? We find the camper can get very cold when going down the highway after the nice warm truck.
my vents are not covered by the slides:)

Thanks, Tom

There should be no problem. The RV batteries should run the furnace for several hours. Your truck will recharge the batteries when you drive. The RV batteries should not draw on the truck battery. If you are concerned about that draw, unplug the RV from the truck while running the furnace and be sure to reconnect before leaving.

We always leave the furnace on while traveling, that way the camper is always warm when you stop. I have found that if you only have one battery, it will run the furnace for well over 12 hours if you watch your usage on other items. The only time we ever had the battery go dead, I had forgotten to unhook the emergency brake when I unhooked and the cable stayed pulled out all night. Between the heater and the brakes, my battery was dead and I woke up freezing.

Depending on how high/low you have your thermostat set, one class 27 battery will drain pretty fast if the furnace is constantly blowing. Use caution.

TC

I am only talking about during lunch, so should be no problem.

Thanks, Tom

We have used our heater while stopped for lunch without any problem. One time we stopped for lunch on a cold day and it was already warm inside. We forgot to turn off the furnace before leaving the campground. No problem there either. Just wasted propane. Our trailer heats very quickly with the slides in, so when we stop, we are warm fast.

Tater