question regarding electric element in water heater

[manorlife]

I tried searching but could not come up with the answer that I was looking for. In a boondocking situation where you fill up the water tank and presurize the system and turn on the heat element for hot water... I'm just wondering what happens if say you are taking a hot shower and you use up the last gallon of water in the system. will the electric heat element burn out since the water tank is now empty? or is there some sort of fail safe built in where it will not drain the last few gallons so the element is always submerged into water...

[rvcycleguy]

Maybe I'm reading this my way but if your boon docking, your not using the electric water heater element. Your using the gas fired side of the water heater. Unless your using a generator that you have not mentioned.

[Bill]

Manorlife -

The water pump will not drain the water heater. I think your mental picture of the water system is not right. Take a look at one of the plumbing system diagrams, such as the one here

http://www.trailmanorowners.com/foru...&pictureid=435

You can see that if you start with water in the fresh water tank, and turn on the pump, and draw hot water from the shower or sinks until the fresh water storage tank is empty - the water heater will still be full.

HTH

Bill

Nothing prevents one from draining the hot water tank except hopefully you would notice nothing is coming out of the cold water supply and therefore the water would also be very hot?
There is no "fail safe" per se.

[MudDog]

Originally Posted by moaboy

Nothing prevents one from draining the hot water tank except hopefully you would notice nothing is coming out of the cold water supply and therefore the water would also be very hot?
There is no "fail safe" per se.

Water pressure is needed to push water out of the hot water tank. If you had electric hookups, but no water hookups and instead were using the fresh water tank with water pump, you would lose water pressure when the fresh water tank went dry.

The hot water tank would still be full. Only way to drain the hot water tank is the HW low point drain valve (gravity).

It's just like a home hot water heater. If you turned off your water main, the hot water heater would still be full...though without water pressure you can't get to it from your faucets. Only way to drain it is the drain valve at the bottom of the tank.

--jim

[manorlife]

thank you everyone... excellent responces and diagrams. it answers my question perfectly. much appreciated... the OP was just a hypothetical BTW. I would suppose that it could be simulated with a generator while boondocking. there are other situations that I can think of where you may want to use the water tank (ie no city water) and still have electrical power. again thanks everyone.

Originally Posted by manorlife

thank you everyone... excellent responces and diagrams. it answers my question perfectly. much appreciated... the OP was just a hypothetical BTW. I would suppose that it could be simulated with a generator while boondocking. there are other situations that I can think of where you may want to use the water tank (ie no city water) and still have electrical power. again thanks everyone.

Actually there are quite a few campgrounds with only electricity and no water.

We just spent a few days at Flamingo campground in the Everglades N.P. Florida and it's like that. Also many Ontario Provincial Park campgrounds have only electricity.

And if they have water, some northern campgrounds will drain their water pipes in the fall but leave the electricity on for winter camping. Geneva S.P. on Lake Erie in Ohio is like that. We usually stay there on our way to Florida in November.

So not an uncommon situation at all.

Many PA state parks are like that. They have electricity, but only a communal water spigot. In my book once one has electric you can get by much more easily.

[ThePair]

Many Wisconsin sites are like this as well. In fact, in three years I have had electric 100% of the time, and only had water once (staying in a visitor's slot at a semi-permanent camping situation.)

Doing without water hookup is simple. Doing without electricity? Still trying to convince the DW it's possible...