We moved into our house 4 years ago. The house is 22 years old, with copper pipes. Since we moved in, we have heard a strange engine or rocket-like sound coming from the walls below the upstairs bathroom. It actually sounds a lot like a really loud, short blast of white noise moving through the pipes. It used to happen only in a while, but has been happening more frequently lately, often going every 20 seconds or so for half an hour at a time. It only happens when there is no water running anywhere in the house, usually starting 10 to 30 minutes after the last time a faucet was open.

The higher frequency of noises started soon after I replaced a leaky cartridge in the shower faucet last week, but the sound is the same as before. There is no hammering, clicking, groaning or ringing, just short rocket blast sounds.

Plumbing sounds can be a bear to track. Lets start by looking at that cartridge. Do you have lintegral shut offs so you can take the shower valve out of the loop or do you have to shut the main

No integral shut offs. I have to shut off the main.

That make4s it a bit tougher to isolate the shower since I am sure you did not save the old cartridge, maybe you can exchange the cartridge you have. Do this only if the sound started right after the install and never before. Also don't type in the comment box, use the ANSWER THIS QUESTION box below