Why is my water heater still leaking at the relief valve on top? I've changed it twice. Also I have 160lbs of pressure and have changed the regulators three times. Doesn't make sense. Please help!
I think the pressure on your house plumbing should be about 80 psi or less right after you run a tap and then shut it off. Do you have an expansion tank to prevent pressure increase? If you use a lot of hot water, then don't use any water, the pressure in your system can increase as the cold water in the tank water heater expands on being heated.
If this is what is happening, if your TP valve is dripping, then it should stop if you momentarily open a cold water tap (or if you open a hot water tap but then more cold water would flow into the tank causing more expansion after a while).
See pressure relief tank.
EDIT Informative readings here from Watts.