Holding tank heater


New Member
My Prowler TT has an totally exposed fresh water holding tank that has a factory installed heating pad on the side next to the water demand line, an Ultraheat TH726 13.5v.

I have never had this type heater on a unit before and want to find out what experience others have had regarding battery drain times with various outside temperatures. How long does it take to raise the tank water temperature say 10 deg with 30 gal water?

What is the proper operation, i.e. if it is 10 deg. outside can I allow the tank to freeze some and turn on the heater each time just before I need fresh water?


Senior Member
Holding tank heater

Actually, the real problem is not having frozen water which can't be pumped; what you are trying to avoid is having any part of your water system burst from the expansion resulting from freezing.

And the pipes are generally subject to freezing before the tank (due to a greater surface area to volume ratio). So once you get any freezing, its possibly too late.

So I don't have personal experiance with that tank heater or any tank heater, but I'll bet the proper operation is to have the heater on at 32 degrees or less, and have a trickle of water flowing or open a faucet every so often so the heated water moves through the pipes.