My hot water heater discharged. Found that the upper element went bad so for my good sense knowing everything was good replaced both heating elements and thermostats and set to a low setting for hot water. After all that was done let it heat up again and discharged once again so i replaced the relief valve. After all i have done it once again discharged and not sure where to go next and have been taking cold showers since even in this below freezing weather.

Any thoughts or further suggestions will be greatly appreciated!!

What is the actual hot water temperature when the T-P valve discharges?

Do you have an expansion tank?

If so, check it for air pressure and / or 'waterlogging'.

If not you may need to install one.

o about actually TESTING the system to see that it is working correctly, instead of just willy nilly replacing things. There are two different types of upper thermostats and if you get the wrong one and wire it like the old one it will NEVER turn off the upper element until it trips the high limit switch.

I had even went back to the old thermostats and still the same issue of overheating.

Is there anything to help with the constant calling for heat?