View Full Version : Moaning/Whistling sound coming from pipes

10-19-2005, 10:00 AM
Over the past few weeks, we've had a high-pitched moaning sound (like a haunted "ghost") coming from the water pipes in our house. At first, we thought we had a dying animal stuck in the attic. It's an interesting case which I've been troubleshooting with no luck. Here's a summary:

- All waters faucets turned off. Toilet shut-off valves turned off. Sprinkler system shut-off valve off.

- Sound occurs during pressure fluctuation as measured with a gage, but only when the pressure drops, which I guess hints at a flow/leak somewhere. Sound is not constant, but rather intermittent.

- Typical pressure drop during sound is from 48 psia to 43 psia.

- House has slab foundation (Southern California) in which pipes run along the floor.

Any recommendations on how to proceed? Is there a leak somewhere which I should be worried about?

Thanks a lot.

10-19-2005, 10:50 AM
I'm not a pro, but to me it sounds like either a pressure reduction valve (if you have one), or a check valve in your water meter (again, not all of them have one). One or both of them is leaking when the pressure drops and the house pressure exceeds the supply.

10-19-2005, 12:43 PM
Check the toilets real well.
If the stops work at the toilets, try shutting them off to see if there is any difference.

10-20-2005, 06:59 PM
Thanks for the feedback. I had already turned-off the toilets' water supply, so it can't be them.

As far as the pressure regulator, it's only a year old, but I guess I can buy another one, install it, and see if it makes a difference. I just looked up the same part # as currently installed and it looks like it's around $35.

10-23-2005, 09:31 PM
Last Fall, a very strange sound began happening intermittently in what sounded like the attic over my master bath and closet. I was convinced it was bees or some other insect. Contractors I was interviewing for a remodel job also thought bees. Well, we are in month 5 of the remodel, which involved emptying the master bedroom, bath and closet, and now the sound really echoes. I borrowed a stethoscope to see if I could pin it down. I had pest control come out, but they found nothing and speculated on it being in the pipes (this 5-yr-old house has plastic water delivery pipes). I have narrowed the location of the noise (I think) to a wall cavity shared by one end of the master closet and a coat closet in the foyer on the other side of the wall. Desperate, I cut a hole in the sheetrock and found...nothing. The whole house water shut off valve is in the coat closet, however.

My moaning sound is accompanied by some mysterious tapping or light knocking sounds also. I am not sure I can live in this bedroom if I don't get this figured out. Of course, since it's intermittent, it is especially hard to diagnose. I don't have a pressure guage. My house is on city water.

I sure hope someone has some other ideas for this wierd sound. It is driving me crazy.

01-27-2007, 06:13 PM
I was hoping to see more replies - especially to the last one. We are occasionally hearing a low moaning sound like wind through a slightly opened window (but not much variation in pitch) and sometimes it sounds like a low growling sound. It is always accompanied by an irregular tapping sound that sounds like metal (our house water pipes are plastic, gas lines of course are metal). The sound is coming from inside a wall in our downstairs half-bath, which is under the stairway to the second floor. The house is about 19 years old. We sometimes hear the sound 2 or 3 times in one day but sometimes it can go for days with no sound. It began about 6-8 weeks ago.

Any ideas?

Plumb or Die
01-29-2007, 04:51 AM

01-29-2007, 07:12 PM
I get those exact same moans whenever I forget to shut off the garden hose, like after I wash the car. The whole house whines.......