Symptom Help - Horn/Whimper Pipe Noise

Hello all...

We've got some type of problem now ever since returning from vacation. When the water is shut off anywhere in the house (i.e. using faucet and shutting off, post toilet tank fill, post washing machine fill, etc.), about a second or two after a distinct horn-like, or groan-like, noise is heard. My wife even says it sounds like a short dog whimper. We have not had this problem before, and as I said it seems like ever since return from vacation. The trip was a little over a week, and we shut off the main water valve in the basement when we go to prevent against a pipe break, or whatever, and potential flood.

Does anyone know what this could be ? Things to check ?

Is there any reason that water should not be turned off for extended periods of time ?

Forgot to add, the house is only 5 years old, so this is not an "old" piping issue, and main valve is a lever-type.

Any help/suggestions greatly appreciated !

Ron

Pipe Noise

Does anyone know what this could be ? Things to check ?

Could be pressure fluctuation in the system and a toilet fill valve is making the noise, could be a water pressure regulator malfunctioning, could be a water treatment system malfuctioning.
Try to isolate or pinpoint where the sound is originating from. A plumber may need to troubleshoot this for you.

Is there any reason that water should not be turned off for extended periods of time ?

Some people do shut their water before leaving for a vacation but most do not. It cannot cause harm to the water distribution system but if you have an automatic irrigation system, fire protection system or a heating system that requires an automatic water feed to operate, you could have some issues.

noise

It is usually either a pressure reducing valve or water softener making the noise. If you have either, or both, listen by it when someone turns off the water.

Fix attempt - Follow up with the latest

Well, last night I tried playing with what appears to me to be a pressure reducing valve located between the main shutoff and the water meter. It is kind of a bell-shaped device, perpendicular to the water in/out pipes, with a screw protruding outward and a lock nut.

Is this the/a pressure reducing valve ?

In any case, I was able to back out the screw approx. 3 turns or so, and it got to the point that I could flush downstairs toilet and after tank fill an water flow stopped I no longer hear the noise. Was impressed with myself and thought I figured it out, until I flushed the toilet in upstairs master bath at bedtime and noted there was almost no flow coming out of the fill line in that tank. I think I reduced the pressure to the point that this, probably being the last fixture on the line, no longer had enough pressure to fill. I went down and turned the screw back in roughly the 3 turns and now it looks like the tank can fill but I'm back to the noise. I must say though that when I try to isolate the noise I wouldn't exactly say that the noise is definitely coming from that device that I was playing with.

Any other suggestions before I have to get someone to come in ?

My thanks again in advance...

Pressure Regulator

If adjusting the PRV stopped the noise, the unit is defective.
It is not worth trying to adjust it again or even rebuilding a small residential device. Install a new one, preferably the exact same one that way there will be no piping changes necessary and you can handle the replacement yourself.

Thanks & question to E-plumber

First, thank you so much for checking in again and providing me with a little more input. I guess the basic question that I had was are you confident that what I was able to rudimentally describe in my update post is in-fact a pressure relief valve, or could I be describing something else ? If you think it is, is this something you can get at a Home Depot or something or will I need to write down the make/model info on the tag of the device and hit up a plumbing supply distributor ? Finally, is this easy enough to do by myself or do I need a plumber...and how do you know how much to "thread-in" the screw to get the proper pressure (do I need a pressure gage or something ?).

Thanks...sorry to bother again....

Yes , this device is the pressure regulator. You should not adust it without having a gauge connected to monitor the pressure. It is very likely that the noises are caused by the regulator ( it has springs and rubber parts, and as these things wear they cause funny things to happen). The units cost between about $45 an $90 depending on size, model. Replace it.