I would suspect the top thermostat first.

The top thermostat is the primary control for the water heater. Only when the top of the water heater is at or above setpoint will the top thermostat shut off and send power to the bottom thermostat. If the top of the tank cools, the top thermostat will shut off power to the lower thermostat/element and turn the top element back on.

Water that is too hot could be the bottom or top thermostat running the temp too high.

But, water that is not hot enough (and the first water drawn comes from the top of the tank) tells me the top thermostat isn't coming back on as the water temp drops.

Do you have scald-protective shower valve? Using a cooking thermometer at the kitchen faucet will reveal the water temperature. Run the hot for about 5 minutes, then read the temperature. And the correct terminology is simply "electric water heater".

Buss driver,,,

I got a chuckle out of your last comment about the correct terminology is simply an "electric water heater"

When I was going to tech school studying for my high pressure boiler license I saw one of the most heated arguments I have ever witnessed over that very same point.

One of the students had failed an exam by one point, and when he reviewed his exam he found the instructor had marked a question wrong because he used the phrase "Hot water heater" in place of "Water heater"

The instructor told him in no uncertain terms that a "water heater" produces hot water. On the other hand, a "Hot water heater" produces steam and should properly be called a "Boiler" therefore your answer is wrong however you look at it.

Thank you very much "Formula1," I will check that out today and replace the thermostat if necessary. Your explanation was perfect. Thanks again :-)

Bus Driver: #1. I don't need scald protection for my shower. #2. I don't need to waste precious water for 5 minutes to test the temperature... it's too hot! #3. I didn't ask for an english lesson!!!! You were absolutely no help with your answer!

Lazy Dog: You must like to hear yourself type! This reply doesn't belong here. It belongs directly in Bus Driver's mailbox.. not here. I had nothing to do with MY question.

I have a gas fired water heater that does the same thing, first shower in the morning is lukewarm and the second is steamy hot, just depends where you catch it on the cycle, at the top or the bottem.

All the pros that are on this forum like to hear themselves type because they sure don't get paid for it, they're just interested in people.

frugalflowers sounds like a customer we used to have, 4 people waiting on customers and when he walks in they argue about who has to wait on him. You hear "I did it yesterday so it's not my turn".

I got the hot water heater part right this time.

It is unlikely that frugalflower will be able to recognize help when it is offered. And certainly he/she hinders good advice by not supplying additional information when requested. A scald-prevention shower valve limits the amount/temperature of the hot water that it will deliver. Certain of those might operate erratically and deliver hot water at varying temperatures. That appears to be the original complaint. But attempts to help this person have been rebuffed. I hope they find an answer they like.

FrugalFlower:

I can tell by your attitude that you are accustomed to getting everything your own way but, let us examine the facts here:

1.There is not one scintilla of information in your original post that would support your notion that the problem is confined to the water heater.

2.Buss Driver had already given you the correct response so what good would it have served if I were to redundantly offered the same answer?

3. Anyone who has followed these boards for the last 4 or 5 years knows full well that both Buss Driver and I spend countless, or should I say thankless hours answering questions in finite detail and in the process if we should stray off point a moment to share a little humorous quip, so be it. Let's face it here, if you had called my place of business, and if you were paying my $95/hr service rate you would have been entitled to an all business approach to your problem, but since you elected to try to avoid a legitimate service charge by posting on a forum in the hope that you could get credible diagnostics for free you have to expect that not all the replies will be factual or directed solely to your needs. The bottom line, you got what you paid for.

On the other hand, when Formula1 offered a rudimentary explanation of how a water heater works, you took that to be gospel and headed off to check the thermostats. I would be willing to bet my first born son that you have not got a clue as to how to check a thermostat other than to see if it is really there, or perhaps press the reset button in the blind hope that it would solve your problem.

Now in regards to whether I like to hear myself type? The answer is yes. Not only do I like to type, I actually proof read what I type before I post it, which is more than I can say for you. Case in point, refer to the last line of your reply to me:

Quote "I had nothing to do with MY question."

That comment begs the question, if YOU had nothing to do with your question, then kindly explain who did? Even more to the point, why did that person waste your time and mine by posting a question in your name?

Now I am left with but one more question; is this really a "Frugal Flower" or is it perhaps a "Cheap Bloomin Idiot"?

It's possible that your water line is reversed. Many water heaters are incorrectly installed in regard to the water line -- are the mistake is usually that it is reversed. You can easily tell if the water line was installed reverse by touching a pipe several feet away from the unit and comparing it to the hot outlet fitting that is at the top of the tank. If your heaterÂs connection is reversed, it is not operating efficiently. Since hot water rises, the cold water should enter at the bottom of the tank, so it doesnÂt have to mix with the hot water. If it enters at the top, then it ends up cooling the hot water, which has to be heated again and thatÂs where energy is wasted. Additionally, according to Accurate Inspections, "If flex water lines are not installed, they should be. If a cold water shut-off valve is not installed, one should be."

Here is a link that might be useful: Accurate Inspections

If you choose to use electric hot water systems for your home, you will never run out of hot water to use. This is because you can easily heat water as soon as you�re out of it. Because it instantly heats the water, you can be sure you get hot water the moment you need it.

Here is a link that might be useful: hot water systems