Leaving tank heater pads on.

[Cougarnewbie]

Truck broke down in Richmond Virginia. Can't move for at least a day. It is forecast to be below freezing for the next 40 hours. We are in our new Cedar Creek. (Forest River) It is equipped with tank heating pads. I have never used them before. Can I turn them on and leave them on? Book says to have water in tanks. Not sure why. My fear is on the order of cooking an electric element like the regular hot water heater.
Thanks for any advice
AL

[I-Can-Am-Can-Yo]

bpounds wrote:

Farmboy666 wrote:
...Hot water freezes faster than cold water...

Huh?

lol I think he's referring to the Mpemba Effect which is a theory I never considered applying to my holding tanks...

[laknox]

bpounds wrote:

Farmboy666 wrote:
...Hot water freezes faster than cold water...

Huh?

More properly, boiled water freezes faster than non-boiled water. You drive air molecules out of the water, which means the water molecules are "closer" together meaning faster heat transfer. This is why "regular" ice is opaque and soft but "crystal" ice is clear and hard.

Lyle

[bpounds]

Farmboy666 wrote:
...Hot water freezes faster than cold water...

Huh?

[shum02]

Tank heaters are around 40-60 watts, just enough to keep the liquid in the tanks from freezing and most AC powered ones are thermostatically controlled. If you leave them on and the tanks are empty you will more than likely cause no damage to the tanks but probably will burn out the tank heaters.

If you don't need them on, don't turn them on and as said they will not help the water lines/sewer lines in the least.

[Farmboy666]

Tank heaters aren't going to do anything for the plumbing. Hot water freezes faster than cold water so that's no help but at least you put water in them.

[Cougarnewbie]

One switch for all heaters. Empty or full. At a KOA. Good electric. Enough propane for the night. We are cozy. Just concerned about the belly plumbing. Ran hot water into grey and galley tanks. Gonna leave heater switch on. See how it goes. Thanks.

[rhagfo]

The pads on our tanks are only activated if the temperature gets below freezing.

[GordonThree]

Fear is softening the plastic tank and causing either seam failure or a joint to external pipe or hose to fail. The pads do not get very hot. They're only 40-100 watts spread over a square foot or two. Unlike your water heater which could be 1500-4500 watts over a few inches.

If your tanks are empty why do you want to heat them?

Will you be staying in the coach while the truck is getting repaired, will you have hook-up?

I'd leave the furnace or electric heat on if the plumbing is not winterized.