Water heater virgin has a question here, LOL

[1Garageman]

Ok, I have never messed with a water heater before, except helping dad carry them up and out the door.

My question is we have in our house two water heaters. We have lived there for about two years now and I think that we have to push the heat over further now to shower and other things to get our hot water. I was wondering if one of the water heaters might be going bad? I am not sure how to check?
Feel the out side of them for heat? They are electrical powered.
Could you guys give me some ideas on what to look for??

Thanks!

 

[Warrenator]

You can use an ammeter to check each heating element for resistance. Disconnect the heavy wires right at the heating element (unplug or circuit breaker off the water heater from power first unless you like sparks and hospitals) and check each element for resistance, if one has gone bad it will be different (open or shorted) from the others. You can buy new elements at hardware stores, need a big/deep socket wrench to remove them, also available in the store next to the heating elements. Use pipe dope when you put in the new one. Oh, and you need to be a gorilla to get the old ones off.

You might also have a thermostat problem. It's kinda hard to tell from the way you describe it. Are these instantaneous (tankless) water heaters or the tank kind? I'm assuming you're talking about the tank kind. If the water never gets to a high enough temperature unless you monkey with the thermostat, but then it's fine, the thermostat might be faulty. If the water gets plenty hot but takes a long time to recover, I'd suspect an element. If the water is plenty hot but seems to run out immediately, I'd suspect a dip tube, especially if there are bits of crud in the hot water screens on your faucets. (Google water heater dip tube, this is a common problem for certain years of manufacture)

 

[larry_g]

I would check for a date on them before doing much else. If they are 20+ years old you may not want to spend a large amount repairing them. CAn you read the data plates on them? If so they should tell you the mfg date, element wattage, and capacity. Do you know why there are two water heaters in the house, and how they are plumbed? Do they both feed the hotwater system? or are they for different areas of the house? Most houses have only one HW heater so you have something out of the ordinary and before giving opinions a few more details are needed.

Electric HWH usually have two elements in them, one high and one low. The low one does a majority fo the heating. Only one element comes on at a time. Do you have an amp probe to check current draw on the elements?

lg
no neat sig line

 

[Charles (in GA)]

A tank water heater of more than about 20 gallons has two thermostats, and two heat elements. If you begin with a full tank of hot water, both thermostats are satisfied and both heat elements are OFF. As you use hot water, you are drawing from the top of the tank (heat rises remember) and the cold water enters and travels down the "dip tube", most of which nowdays, have a curve at the bottom end of them. This curve creates turbulence and keeps sediment from accumulating on the bottom. The cold water that enters stays on the bottom (cold water is heavier and settles, so it stays on the bottom), creating a huge stratification of temperature in the tank). When the bottom of the tank gets cold enough, as more and more cold water enters, the bottom thermostat turns ON the bottom heat element, to heat up that cold water.

If you stop drawing hot water at that point, the lower element will heat the water, and the thermostat will satisfy and the lower element will shut off, and the water heater will be "at rest" ready for the next use.

If you continue to draw hot water, the level of cold will rise in the tank and the lower element will not be able to keep up with it, soon the tank will be full of cold water, and when the top thermostat senses cold up high in the tank, it switches OFF the bottom element, and turns ON the top element, in a last ditch effort to provide you with some hot water.

If at this point you cease to draw hot water, the top element will continue to heat the top of the tank until the top thermostat is satisfied and it then switches OFF the top element and allows the lower thermostat to turn ON the lower element if it needs to (and it will, as the lower part of the tank is still cold) and the lower element will heat up the water until the tank is entirely hot, and the lower thermostat is satisfied, at which point the lower element is switched OFF and the heater is "at rest" again.

The two elements are NEVER on at the same time, as this would overload the circuit.

Charles

 

[1Garageman]

OK, you guys gave me some homework to do this weekend

I have an AMP meeter and can check and see how many amps it is drawing.

The house was built in 2007, so I the water heaters shouldn't be more than 5 years old, I would assume. I will have to look at them and see.

I will have to do some investigating and stuff. Gives me something to do while my mother in law is visiting!