I have a Delta scald guard and I had a leak both from both the shower head and the valve itself. I know about the leak from the valve itself because I can see the water dripping from the ceiling of the main floor. I bought a new valve and replaced the old valve and it stopped the leak in the shower head. The leak from the valve also stopped for couple hours but then it came back, now it is dripping just like before.
Not sure if the leak is in the copper pipe, but the leak is definitely from or very close to the valve, since I can see the water droplets dripping off the valve. Any suggestion?
Wrap the pipes and valve with paper towels--this will show if the leak is in the valve or coming from above---The most common leak is from the chrome shower arm---I always use dope and tape on that one.(TPE paste)
If it's not the valve and not the eared flange (where the shower head arm is screwed in) then there might be a coupling in the pipe leading to the eared flange.
Good luck with that---I bought a snake camera to track down these very problems.---Mike---
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