Hot water tank

It is a good idea. It won't over heat as it is thermostatically controlled. Your pressure relief valve probably needs to be replaced. Try opening and closing it a couple of times to see if it reseats itself and stops dripping.

RV water heater is just a smaller version of your water heater at home.
Cold temps........leave it ON so water in tank stays hot. Helps keep hot system from freezing.

It has 2 t-stats.
A normal t-stat preset for 140*F......when temp reaches set point t-stat turns heating source off. Then allows for heating source to turn back on when temp drops below 110*F
Second t-stat is ECO (Energy Cut Off-----High temp t-stat). If normal should fail to OPEN then ECO opens at preset temp of 180*F and turns heating source off. It will also trigger a 'fault' light.
You have to reset system if ECO operates in order to allow heating again.

The T&P (Temp/press relief valve) can weep when heating. Water expands when heated.....by design the water heater tank has an 'air pocket' in top of tank. The air pocket allows for the expansion of water has it is being heated.
Loss of air pocket can cause T&P to weep due to pressure increase without the air pocket.

Establish air pocket
Turn off water source
Open closest faucet to relief pressure hot side
Open T&P Valve via lever---hold open until water stops running out of T&P
Let go of lever letting T&P snap closed
Close faucet
Turn on water source.

the water heater should cycle on and off according to the temp of the water in the tank and position of the temp control valve, I would be more concerned with the waterlines freezing. If the pressure relief valve is leaking at any time it needs to be replaced that should never weep/leak it should lift (when over pressurized) and reset cleanly.

RV water heater is just like a home water heater. Thermostatically controlled. It will heat or turn off as needed and will not overheat unless it is faulty or damaged and there are safety systems that will shut it down.

When using our trailer, we never shut off our water heater...either gas or electric.

dirtywhiteboy wrote:
Got really cold where we are staying and was told to leave hot water tank on(electric) to keep tank from freezing. Is this a normal way and will the tank over heat leaving it on. I notice

the pressure relief valve drips after left on for a long period.

Thanks for any help.

If your valve is leaking it could be stuck which is VERY serious. If your thermostat is not working correctly and the water reaches dangerous temps it needs to have a working relief valve.

Been there done that and the side of my MH got so hot you could not even touch it when the thermostat went haywire and the relief valve did not work properly.Could have been a disaster for me.

I suggest you have it looked at just to save you what I went thru! :W