Question about Electric hot water heater?

Can anyone tell me, if having the water mains shut off and on all the time (alot) can mess up a hot water heater?

Thank you,
Jeff

Only if the water heater is in a location that lets it drain (i.e., above the lowest level fixture) when there's no water supply, thereby exposing the heating element.

It's in a manufacured mobile home, and it is located in a closet. When the water came back on there was a whole lot of air, and after 2-3 hours no hot water.

It sounds like it drained dry and the elements burned out. As long as the tank remained full or nearly so it wouldn't hurt anything. The big clue was the air in the system. That could only occur if the tank was drained.

Yep... sounds like your service probably does not have a check valve. I'd guess that when the water line was opened for service/repair that it siphoned water out of the water heater exposing the heating elements and probably burned up one or more elements. Turn off the power to the water heater, remove one wire from the element, use an ohm meter to check for continuity between the two terminals on the element. If there is no continuity then it's history. Use a volt meter to make sure the electricity to the water heater is off before sticking your fingers or tools to the wires.... BE SAFE!

Okay, we shut the breaker off just in case, while they were still working on the lines, and had the water shut off. when they were done I went ahead and turned it back on, we had hot water for a short time, but it didn't last long, and took forever to heat up again? Still just the element needing replaced?

Under normal circumstances your water heater should not drain out.

How old is your trailer.

You may have a leak in the water lines under the trailer. The older trailers had PB (polybutylene) water lines that are famous for developing leaks. Have you noticed a higher than normal water bill lately?

It is either a 1992 or 94, it isn't too old. I am pretty sur most of the pipe is plastic or PVC. No, there hasn't been any change in the water bill, and I do notice that, because I have 3 little ones that like to play with the toilet, and leave the water on every now and then.

It does sound like you've burned out one of the heating elements (there are normally two). If you have a multimeter, they can be checked if you know and understand the procedure. Messing with electrical systems can be dangerous if you don't know what you are doing, but are safe if you do and don't get careless. If the tank is more than say 7-years old, it might make sense to replace it and get a new warranty. A tank can last anywhere from a few years (uncommon) to 15 or more (also uncommon). Anything after around 5-7, though is on the down side - it could go any time, or last for awhile; there isn't an easy way to tell. SO, get someone to check and replace the elements and thermostats, and electrically, anyway, it is nearly a new tank and hope, or if it is in that middle-life time, think about replacing it.

The people working on the trailer should have known to turn off the WH while they had the water off. But, as was said, the tanks don't normally siphon themselves out. If an element is uncovered and then turns on, it will quickly burn itself out. It needs the water covering it so it doesn't get too hot (the element, not the water).

Well we actually own the trailer, we rent the lot, and it was a main water line a block over from us they were working on that busted. I am thinking that the water heater may be newer than the trailer. Originally my Grandfather and sister bought this home when we moved him back from Oregon, because of his health, and his family out there got tired of helping caring for him. Anyway he passed away shortly after we got him down here with us, then my sister bought a house, and my family and I ended up getting this place because it's bigger, and newer than what we had.
The most I know for sure about the hot water heater is that it is electric, and I believe it is a smaller or shorter one, as far as the age I'll have to ask about hat to be sure. Right now there is no way we could afford a new wter heater, so hopefully replacing the elements will be good enough.

Two things come to my mind. First, you must find out why the tank drained. It isn't the fault of the tank, so if you just buy a new tank, you will have the same problem sooner or later when the water is turn off for whatever reason. Second thought, elements are relatively cheap compared to a new tank. Now you can tell the age of the tank by the numbers located on the tank, but there is only one thing that will really require a tank to be replaced and that is if the tank is leaking. Things like dip tubes, TP valves, and elements are pretty cheap repair items, and as long as the tank is not leaking, you can get more life out of it by repairing it. Life expectancy of a water heater depends a great deal on your water quality. Some areas have "bad" water that will eat a tank up quickly and other areas, like where I am, have "good" water and a tank will usually last far beyond it's normal life expectancy. To me, scraping a water heater that is not leaking is similar to junking an otherwise functioning car because the battery needs replacing.

The water here is rather crummy, I would say bad, but I don't have much to compare to. One of my sons and I are allergic or something to the tap water so we buy filtered water, and the rest of the family doesn't drink it either. I cook half of the time or certain thing with it, but mostly bath and laundry are the only things we use it for.
My father is comimg down this weekend to look at it (he has more expeience with this kind of work), I was just wanting to descibe the problems on here in hope to get a more persice idea of what the problem is, and what to do. My Dad is the Mr. fix it of the family, his four kids, most of his 9 brothers and sisters, and some of their kids, so he is definately a jack of all trades, and what he doesn't know for sure about he has a book for it.

The parts to fix it are pretty cheap. If you can't do it yourself, the labor to do it might seem pretty expensive. The labor to replace the whole thing may not be that much more in the scheme of things. An electric water heater is easier to replace for a DIY'er than a gas one since it doesn't have gas lines and vents to deal with, so, you pay your money and take your chances. You could go for years without further problems, or you could end up with a leaky water heater next month with new heating elements in it. Knowing the age of the thing can help you make a decision which way to go.

I can pull the elements back out if I end up replacing it a little late to reuse, can't I?

Sure, but they may or may not fit the new one. The best thing to do is to test the ones in there, rather than just replacing them. You would need a multimeter to do this (doesn't have to be expensive - often less than $10 on sale). You might need the thermostats, too. Neither part is particularly expensive. Not knowing your skill levels or experience, it is hard to say do it yourself.