Old hot water heater always had water in the over flow pan from the overflow tube. Replaced with new hot water heater and it's doing the same. I turned the tsat so low that there is never any hot waterafter 10 minutes of shower

Does your house have a PRV (Pressure Reducing Valve) or backflow preventer?

You may need an expansion tank on the cold water line.

I've asked this be moved to plumbing.

Moved to plumbing

You have either too much pressure in your pipes or your heater temperature is set way too high. Check pressure first. Adjust to 55psi.

Keepitsimplestupid asked a good question please respond him, check your water pressure, and let us know, Thanks.

John

Good answers so far. PRV, T&P , TPV seen them called many things but yours may be doing what it is supposed to be doing. If your home has a back flow preventer the water heats up and has no place to go when it expands. That valve isn't supposed to blow until a certain temp or pressure is reached but if you have two in a row that are blowing its time to find out why. Check you water pressure inside the home after no water has been drawn for several hours. If its over 60 psi you need to bring it down but a prv ( not the prv on a heater but a pressure rediucung valve on the main) on the main won't be the answer if the cause is expanding water and a back flow preventer.