I have consulted two plumbers on this one, and both are stumped.
Whenever I use the hot water in the house, about 5 minutes after I turn it off, it starts making short, loud squealing noises (about 5 times, only squealing, no air hammer or rumbling sounds). This does not happen with the cold water. The noise will happen with any of the hot water sources in the house. Here is what the plumbers have done so far: Bled the lines, replaced the entire water heater, replaced the pressure regulator twice. I've had the City check the main line, and they say the pressure increase is not coming from the main line, which is constant at 120. So the pressure must be coming from the house? It has been measured in the new water heater and on the faucet that is connected to the pressure regulator. Pressure goes up to about 100 at the regulator. It seems that the squeal itself is coming from a pressure relief valve outside the house, next to the regulator, but what is causing the pressure?
Whenever I use the hot water in the house, about 5 minutes after I turn it off, it starts making short, loud squealing noises (about 5 times, only squealing, no air hammer or rumbling sounds). This does not happen with the cold water. The noise will happen with any of the hot water sources in the house. Here is what the plumbers have done so far: Bled the lines, replaced the entire water heater, replaced the pressure regulator twice. I've had the City check the main line, and they say the pressure increase is not coming from the main line, which is constant at 120. So the pressure must be coming from the house? It has been measured in the new water heater and on the faucet that is connected to the pressure regulator. Pressure goes up to about 100 at the regulator. It seems that the squeal itself is coming from a pressure relief valve outside the house, next to the regulator, but what is causing the pressure?