I added a pex line from the main kitchen sink to a kitchen prep sink. After a couple of months of perfect use, the sinks still work fine, but at the area of the connection to the pex line, after water is used anywhere in the house (i.e. when it is turned off, or at the end of a flush-bowl refill), it makes a moaning noise. I can't figure out why. Can anyone help?

When you hear the moaning noise can you feel a slight reapid vibration at your PEX connection?

Thanks for helping. I can feel it at the pex t-connection and at the valve.

Tell us what brand of kitchen faucet that you have? One handle or two knobs? Regards, Tom

We replaced the kitchen faucets in both the prep and main sink. We ran the line from the main sink to the prep sink to eliminate a pipe from the crawl space to the prep sink (which was in an outside wall and tended to freeze). We replaced both kitchen faucets with the Hansgrohe single handle higharc pull out spray faucets.

at the end of a flush-bowl refill), Would you be referring to a toilet? Just out of curiosity , how far is the nearest bathroom? I gottahunch that you'll find it in a toilet ballcock I've been out on a complaint just like yours before. Tom

The nearest bathroom is about 10 m, and that bathroom is adjacent to the laundry room. I can hear it at the end of the toilet bowl flush, or at the change in cycle during laundry, or when the dishwasher (adjacent to the kitchen sink) changes cycle. Could a toilet ballcock cause pressure in the entire system to result in this noise? How would I check that ballcock so that I could determine if it's a part of the problem? Thanks.

The problem could be caused by the ballcock trying to fill while water is seeping out of the tank. The sound you hear is the washer vibrating against the seat of the ballcock. First check there linkage between the flapper and the flush lever. It should have 1/4" of play when your tank is filled. The water level should be 1/2" below the white overflow tube after the tank's filled. Next feel the flat side of your flapper. Does it have wavey edges? Do your hands come away black? Replace it if it does. And last check the seat itself. Any nicks or rough spots? If so click on back. There are replacement seats that glue right over the old one and are easy to replace. One of the above should take care of your howling. This happened in a new house some years ago. Only at night and in the early morning. They thought the house was haunted and were about to move out. I caught it in the powder room toilet. It would vibrate and the pipes in the wall would pick it up and carry it all over the house. Hope this helps, Tom

I've checked all the toilets (the one I mentioned 10 m from the kitchen and the other 2 downstairs) with the criteria you mentioned and they all seem fine. Then I turned the water to the 3 toilets off and still heard the moan when I ran a sink. Turned off sinks and heard it when trying from another sink. Turned off the cold water in the moaning sink, and heard the moan from the hot water connection. I'm very confused. Any other thoughts?

Hopefully this will be solved be the process oif elimination.l Let's start with the moaning sink. Shut off both hot and cold supplies to the faucet. Can you still make it moan after flushing or using another faucet? Let me know3 and we'll move on. Good luck, Tom

Tom,

Could this be a PRV?

Tom, Could this be a PRV?
Good question! Darcy, is there a PRV, (pressure reducing valve) installed? Tom

OK, I turned the hot and cold off to the moaning sink and did what you said. Tried a toilet and tried two sinks. Moaned each time.

I don't know if there's a PRV installed. I don't think so (where would I look?). Lived here for over 4 yrs. Replaced the inside prep sink line early this summer. Moaning started this past week.

Go to the next fixture and shut the water off and give it another flush. And then the next one. Sooner or later you'll hit the source and when you do let me know what it is and we'll make it right. Good luck, Tom

The source was a leaky spray nozzle on an exterior hose (not leaking at the hose bib, which has a winter vacuum break, but at the nozzle itself). Turned off, the moan is gone. I haven't replaced the spray nozzle yet but will do so and assume it will work fine. That is simply ridiculous! Thanks for your patience Tom.

Open and close angles stops under both sinks. See if the sound still continues...

OK Darcy,
Just glad you located the source. Smells and noises are the hardest for us to track down. Without being on site to check we're flying blind. Cheers, Tom

I replaced the hose spray nozzle but it did not help. When the hose bib water pressure is on (whether the winter vaccuum break is open or closed) then the kitchen moaning noise occurs. Do you know how can I fix that?

Sounds like vacum breaker. Replace if you find part. Note brand of faucet before shopping.

Thanks. I'll look at replacing the vac. Breaker or seals on the hose bib... and let you know.

Try posting the question under "Paranormal Phenomina".

(sorry... couldn't resist) :)

It was the vacuum breaker. I still say this is ridiculous! Thanks all for the help