Bought a 1972 house with a 5 year old Bradford White 80 Gal WH.
There is a PRV on cold inlet just above WH.
There was no hot water when we moved in, so first thing I did is replace a bad lower element. After replacement, the red cutoff button on the top t-stat pops out after a few hours. (There is no temperature dial on the top element, only the bottom)
The old T&P pushed out a 2 gallon bucket of water per day.
I replaced it with a typical 150psi valve this afternoon. The power to the WH has been off all day since this morning.
In the last 6 hours, the new T&P has let out 14 gallons. (room temperature) OMG I HATE WATER!!
Other notable plumbing attributes:
This is a 5 br house with basement, 3.5 bath, and the hot water trickles while the cold has about 55psi. Copper pipes, and there is no expansion tank in the line. I've reduced the PRV and still no change.