Replaced both elements and both therostats still no hot water?

http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

Replace both thermostats. One or the other is sticking, and there is no way to test which one is bad... since test unsticks a stuck thermostat

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

I have a crown mega store 40 gal water heater. I have turned the therostat down to 0 and still get scalding hot water from the faucets. Is it the theromstat. Unit is 20 years old.

No.
Fold-back elements are low-watt-density, so element does not burn out as easily since heating is spread across more surface area. But recovery remains 16 gallon per hour.
20 amp breaker and 12 gauge wire: max 3800 watts
30 amp breaker and 10 gauge wire: max 5800 watt.
4500 watt element heats 20 gallons per hour.
http://waterheatertimer.org/How-to-replace-water-heater-element.html
http://waterheatertimer.org/Increase-amount-of-hot-water.html
Instead of changing elements: Set thermostats higher so more cold is added to hot water, and then you have more hot water available inside tank.
Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

in big water heater therostat is at below/down side where the inlet/outlet connection are seen.before doing some thing plez drayn out the water of the heater than put the heater on the ground level carefully after that with the help of pliyer & keys open the screws after that u can see there is a heating element & a thermostat is present after that u can replace it.
Note:- If there is some mistak so, plez i'm sorry..................

Safest method:
Shut off electricity to heater.
Shut the water valve.
Drain heater to below the level of the element, open hot water valve in house to vent heater to speed draining.
If the element is on top, you don't have to empty the heater.
Remove old element, install new element.
Leave hot water valve open somewhere in the house.
Turn water on.
Once air is removed at hot water valve, turn electric on.
Shut water valve.

Gary

If your speaking of the element shut off supply to heater open a faucet relieve pressure shut faucet take out element have new element ready to install do quickly & not much water will sneak out...if tstat you speak no draining needed shut off power ..

If you have some hot water from dual-element water heater, then that tells us:
Water heater is 240Volt.
Upper element is working. If upper element is not working, then heater has NO hot water.
Reset button is not tripped.
Electricity and breaker to water heater are delivering 240Volts to heater.

Remaining suspects are:
1) Bad upper or lower thermostat: Solution: replace both thermostats for 28$.
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html
2) Bad lower element: Solution test and replace element:
http://waterheatertimer.org/How-to-test-water-heater-element.html
http://waterheatertimer.org/How-to-replace-water-heater-element.html
3) Loose wire or loose connection: Solution: open both covers and inspect for burning. Tighten all screws very tight.
4) Bad wire: Solution: Buy cheap multimeter from Home Center and do a 30 minute troubleshoot of entire water heater before replacing any parts:
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html
When testing for voltage, rotate multimeter dial to 240-250-277VAC
When testing elements or continuity, rotate multimeter dial to Ohms.

It sounds like the thremostat may be shorting out they are not to exspensive to replace.

It it constantly triping there is a wire touching somewhere.

ohm test elements!! :)

Sound like the heating elements are shorting out. Need to replace them after draininbg the tank. First shut off the breaker. Be safe and good luck