We’ve got some amazing squealing pipes in our house that started about 2 weeks ago. If you run any water in the house, hot or cold, after the water has been shut off for 5-10 seconds, there is a high pitched squeal that lasts about 5 seconds. Occasionally, you can hear a small squeak when you start the water, but that is less common. I cannot isolate where the sound is coming from
Here’s what we’ve tried to no avail:
1) turned off the supply valves all fixtures (including washing machine and dishwasher), one at a time in an attempt to isolate the squeal. No dice – continued squealing.
2) Turned off the supply to the water heater – Effect: squeal did not occur after running hot water, but did occur when running cold.
3) Turned off main supply valve to house, opened all taps to empty water. Turned on main supply and shut off fixtures one by one to blow trapped air out of system. Result – heard squealing while water was running for the first time. Squealing stopped after shutting off water to fixtures in upstairs bathroom. However, after an hour of listening to all fixtures in the bathroom, unable to locate squeal. Squeal continued after this exercise, and if anything, got worse.
4) Replaced all fill valves to the toilets. They were old and I read these are often a problem. No effect.
5) Looked for leaks on all visible pipes, in basement and at all shut off valves. No leaks found.
Two things I can think of is you have a leaky flapper are the ballcock is running slow and shuts off and squeals. If you have a PRV on the main line ( which it sounds like could be the trouble) turn off water and take apart and clean and get some Plumbers grease and grease the rod.