I am having a problem with occasional drips from a shower head with a relatively new shower faucet. The faucet has both a pressure balancing unit and a temperature control cartridge. I've already tried changing them both out.
I temporarily put a pressure gauge in place of the shower head and I see a regular pressure of 65 psi with occasional bursts of up to 120 psi if a sink faucet is shut off abruptly. I also see some minor pressure fluctuations due to things outside of my house.
Interestingly once I have at least 40 psi in the gauge, even if I shut off the shower faucet, the pressure continues to rise to 65, and the pressure bursts come through as if the shower faucet were open.
What should be the expected behavior in the presence of pressure wave slams?
Should a faucet cartridge maintain a positive shut off even with pressure bursts? I think the faucet is designed for up to 100 psi - perhaps there is a standard margin for temporary bursts above that?
Also, I understand that the plumbing code prevents putting a complete shut off at a shower arm. Is this due to risk of hot water mixing back into cold water that could come out a sink faucet? What is the risk?
I temporarily put a pressure gauge in place of the shower head and I see a regular pressure of 65 psi with occasional bursts of up to 120 psi if a sink faucet is shut off abruptly. I also see some minor pressure fluctuations due to things outside of my house.
Interestingly once I have at least 40 psi in the gauge, even if I shut off the shower faucet, the pressure continues to rise to 65, and the pressure bursts come through as if the shower faucet were open.
What should be the expected behavior in the presence of pressure wave slams?
Should a faucet cartridge maintain a positive shut off even with pressure bursts? I think the faucet is designed for up to 100 psi - perhaps there is a standard margin for temporary bursts above that?
Also, I understand that the plumbing code prevents putting a complete shut off at a shower arm. Is this due to risk of hot water mixing back into cold water that could come out a sink faucet? What is the risk?