Plumbing: water pressure and noise mystery

[Bob Vavricka]

I have plumbing mystery and I am posting this knowing the great amount of expertise in this community.

I have a water softener and it started making an intermittent noise a month or so ago. I rebuilt the head 5 years ago and decided to just replace it. Unfortunately, the noise continued with the new head and I have decided the noise wasn't caused by the head but from the water pressure fluctuating causing the head to make the noise. I have linked to a video of a water pressure gauge and the sound the water softener makes. If I unplug the softener head, the noise continues, if I bypass the water softener, the noise stops, but the water pressure gauge continues to fluctuate. No water is being used when it happens and if I turn on the water, the noise will stop, but start back up when the water is turned off. This can last from a few seconds to several minutes several times a day. The noise is loud enough I can hear it through the wall of my house with the softener in my garage. Any ideas what could be causing this? https://youtube.com/shorts/hlO7DXdXp0I?feature=share

[Bill Dufour]

I would guess water hammer. Your pressure is way to high. 60 Psi is more then enough. I would install a pressure regulator for the entire water supply inlet.
City water? Ask them to regulate it in the neighborhood.
Any hammer arrestors in the house? They are probably waterlogged and do no good.
Bill D

Check your water heater tp valve.

[Bob Vavricka]

Bill,
I know the water pressure is high, but it's been that way for 33 years and the noise just started.
A pressure regulator is a good idea.
It is City water. No hammer arrestors in the house.
I'll check the water heater relief valve.

[Lee Schierer]

I agree that the water pressure is too high. 90+ psig is excessive and you are likely going to damage faucets and valves in your system. I would install a pressure regulator. Most likely the pressure has damaged the bypass valve in the water softener that opens when the softener recharges. If you check the water softener drain tube you will likely see water coming out most of the time.

Any solenoid valve in your system such as the washing machine, dish washer, fridge ice maker and water dispenser and the safety valve on the water heater may be getting damaged or weeping. If you hear any rattling or banging of pipes when the washer fill shuts off or if you quickly close a faucet you are having water hammer. Water hammer can result in catastrophic piping failures.

[Stan Calow]

I dont know how old your house is, but there should be a pressure regulator valve somewhere in the system. Sometimes they wear out. if that doesnt help, then you need water hammer arrestors in your system at the points of use. Those things wear out too.

[Cameron Wood]

Some possible culprits:

- washer fill valve, try shutting off washer taps
- shower mixing valves, sometimes on/off valve is left on, relying on mixing valve to take pressure
- tempering valve at water heater
- toilet fill valve cycling from debris & or excess pressure
- Irrigation control valve, same

The intermittent correlates with toilet fill valve.

[Bill George]

Install a water pressure regulator, no they do not come with a house unless someone asks for it.

[Maurice Mcmurry]

Its is a weird problem, almost spooky. I think the fluctuation may be in the municipal water supply. In the process of installing a regulator you could test the main with the house piping isolated.
Our town water pressure has been increasing as the town grows. Expansion tanks at the water heater and pressure regulators were made mandatory several years ago.
Our town also ended the requirement for air traps at every fixture. It used to be that a T with a 12 inch vertical pipe and a cap was required at every fixture. This was done away with after dead end pipes had been linked to legionella contamination.

[George Yetka]

Are you on well water? If so the tank may be damaged or the air fill level too low. The tank would take hammer out. If this is on city water You can add a tee on your water inlet with a 1 gallon ET that would eat that hammer.

[Maurice Mcmurry]

I watched the video again and wonder if the softener is recharging when the sound occurs? On some softeners the only electrical part is the timer clock. Does recharge continue when the unit is unplugged? Recharge would stop when bypass is pushed. The bouncing pressure must be causing some internal parts to move and make noise?

[Bob Vavricka]

House was probably built in the 60's. There is no pressure regulator. In the 32 years I have lived here, I have replaced/modified probably 80-90% of the water lines. Originally copper under the concrete floor on the 1st floor and galvanized in the floor of the 2nd floor. All the copper under the concrete has been replaced with PEX in the floor joist space as I have remodeled and replaced ceilings. No pressure regulator in the system although I will probably put one in just past the water meter. I may try checking to see if this still happens while I have the house isolated from the system, but since it is so intermittent, I'm not sure I'll be able to wait long enough to tell. Today, the only time I heard it was early in the morning and only for a few minutes. I don't really have a water hammer problem and putting them in at point of use would be a problem in most cases.

[Bob Vavricka]

Most likely the pressure has damaged the bypass valve in the water softener that opens when the softener recharges. If you check the water softener drain tube you will likely see water coming out most of the time.

Any solenoid valve in your system such as the washing machine, dish washer, fridge ice maker and water dispenser and the safety valve on the water heater may be getting damaged or weeping. If you hear any rattling or banging of pipes when the washer fill shuts off or if you quickly close a faucet you are having water hammer. Water hammer can result in catastrophic piping failures.

The water softener doesn't have any water coming out of the drain tube except during regeneration. The head information says it should be put in a system with over 125psi and the old head I replace had been in service for over 20 years without any problem. I will probably still install a PRV, but I don't believe that is the problem. I may be proven wrong.

[Bob Vavricka]

I watched the video again and wonder if the softener is recharging when the sound occurs? On some softeners the only electrical part is the timer clock. Does recharge continue when the unit is unplugged? Recharge would stop when bypass is pushed. The bouncing pressure must be causing some internal parts to move and make noise?

No, the softener is not recharging at the time this happens. I believe you are right that the bouncing pressure creates the noise at the head. If it wasn't for the noise at the head I wouldn't even know it was happening. Spent $300+ to replace the old head because I originally thought the noise was created by the head.

[Bruce Wrenn]

Because you don't have a pressure regulator, water hammer could be coming in on service from street. The force of the moving water in pipes has to go somewhere. Not just yours, but the guy down the street also. That's why fire departments SLOWLY turns of hydrants. With a regulator, you will need an expansion tank for water heater.