My 50 gal elec water heater model #81v52d only stay hot during a shower for 10 min how do I make the water hotter is there a dial on it?

if there is no reset button, you should be able to turn the breaker off for a few minutes. then turn it back on. if its an electric water heater! it should reset it. good-day !

the lower element is located behind the lower panel. Take both screw out and remove the panel. Insulation will probably be in the way so you will have to push it out of the way. The element is round on the endand has two wires going to it and will probably have screws you will have to loosen to take the wires off. (Before you do anything, disconnect the power.) Take the two wires off of the element. You will need a cheap ohm meter. Check for ohms across the element.(One needle on one terminal and the other needle on the other terminal. If you get no ohms or your meter does not move , the element is open (bad) If the ohm meter moves, your element is still good. If you have to replace the element, you will have to turn the water off, drain the water heater, and it takes a special wrench you can buy at home depo to screw the element out of the water heater.

It's probably bad upper or lower thermostat.
BUT... new element could also be shorted.
OR ... original tank is rated 1500 watt elements look at label on side of tank.
I always replace both thermostats to save time.
Lower thermostat costs $10 at Lowes.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

Add a comment for more free help.
Also take advantage of fixya phone service.
For a price, expert speaks with you over phone while you work on heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

The first thing I would do is to turn the thermostat up and down several times,wait a few mins. and do it again. Then run hot water until element comes on. Let it run for a few mins and then turn it back to lowest setting.
I never really came up with a good reason why this works some times but I always tried to save money for my customers and quite often I was 30 or more miles to supply house and it was a cheap fix.
I think you probably will end up replaceing thermostat like your thinking so good luck. Thank you.

check the fill tube

I would say your water heater is from the fury series; new model number 82V52-2. I've included a link with my solution that you should take a look at. You could also look at water heaters of a different brand if this one isn't available in your area. Kenmore, GE, and Hotpoint are all very good brands of water heaters.

http://www.rheem.com/product.aspx?id=09DF2BDD-5E11-4D32-B574-84ACFB8A4619

one element is off peak and one is boost could be thermostat or ripple controller in fuse box or one dead element

You can eliminate the shower control knob possibility by turning on your hot water anywhere else in the house. If you get hot water in other places, then it could be the knob causing it. A substantial lime buildup in the tank can also cause poor heat transfer from the elements to the water.

Makes you feel good to save some money right? Have a great day!

you have a couple things that may cause this. you may have a bad element a bad thermastat a tripped eco (emergency cut off ) or problem with electric suppling heater.if you have no electric backround or training you should call a pro