Vibration in water pipes

[Ook]

I have a unique situation where my hot water heater is fed by city water @ 60psi, and my cold water comes from a well at 30-45psi. I have a pressure compensating shower valve, it is designed so that if the water pressure on one side drops, like someone flushes a toilet, it compensates for this so that the water temperature coming out stays the same.

When I use it, and have it set to mix hot and cold at certain temperatures, I get a vibration in the pipes, and the water coming out of the shower head pulsates at about 4Hz or so. My guess is this pressure compensating shower valve cannot properly adjust to the extremes in water pressure difference, and/or isn't properly dampened, and so it oscillates instead of stably regulating the temperature.

Replacing it is easy - after I tear out the walls. Don't really want to tear out the walls. Anyone have any suggestions as to what can be done about this short of just replacing the shower valve (assuming it is the valve causing the problem).

[dpb]

Put a pressure reducing valve on the supply line to operate at roughly same pressure as other supply side.

Just out of curiosity, why this setup?

[Caesar Romano]

On Wed, 13 Jun 2012 13:04:27 -0500, dpb wrote Re Re: Vibration in water pipes:

I don't think that will work as the well-side pressure will vary between 40 and 60 psi (or whatever he has the on/off set points).

That really is a strange set up. If it was me, I would switch to one or the other for inside water.

[dpb]

Not _after_ the reducing valve/regulator reduces it to the 30-40 or whatever the city pressure is. That nearly isolates the downstream from the upstream side which is the whole point. The regulator goes on the feed to the house from the outlet of the pressure tank; the tank/well are as before.

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[Vic Smith]

First thing to try is throttling the valves that supply the compensating valve. Some combination might eliminate the harmonics, without reducing noticeably flow.

[clare]

Feed the cold water for the shower from the city water, same as the hot and the problem will be gone.

[clare]

But he would need a regulator on BOTH the city and well water supplies then.

[dpb]

...

Why? He's said the city supply is roughly right for household, all he needs is to get the well supply roughly equivalent instead of double it.

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[clare]

Except the city water is higher pressure than the well, from what I remembered of the original post.

[clare]

Original post - I have a unique situation where my hot water heater is fed by city water @ 60psi, and my cold water comes from a well at

30-45psi

I'm not aware of a pressure regulator that will raise the pressure, so if the variation of pressure between 30 and 45 PSI is a problem that needs regulateng ( to 30, I would assume) then the cyty water also needs to be regulated down to 30. MUCH simpler to just feed the cold water to the tub from the 60ps1 city water.

[dpb]

On 6/13/2012 9:14 PM, [e-mail] wrote: ...

OK, so I reversed the higher...use your head.

The point is bring the higher to match the lower.

[Caesar Romano]

On Wed, 13 Jun 2012 22:17:40 -0400, [e-mail] wrote Re Re: Vibration in water pipes:

Exactly.

[CRNG]

On Thu, 14 Jun 2012 22:57:04 -0700 (PDT), Ook wrote Re Re: Vibration in water pipes:

Water around here is $3/1000gals, which I consider pretty high. High enough to keep us on a well.

How about something like this

T-connected to the cold water? It might help, but I doubt it. If it was at all possible, I would try to just switch to the well exclusively.

[clare]

We use 21 to 23 cubic meters of water every 2 months for the 2 of us. That's about2700 to 3000 gallons US per month

[CRNG]

On Fri, 15 Jun 2012 19:18:05 -0700, "Steve B" wrote Re Re: Vibration in water pipes:

Wow. That's pretty complex.

Typically, adults use about 1500 gals/month each *within* the house. That amount is remarkably consistent and does not include any outside use such as lawns, gardens, swimming pools, etc.

[Evan]

ROFL...

The damned shower valve is performing according to its intended purpose... Making the higher pressure water feed intermittent to prevent scalding... If you want it to stop either regulate your city water feed down to the pressure level of the well water or install a jet pump on the well feed into the house to boost the pressure to match the city feed... Then the valve will stop making noise when the water sources on both sides are of equal and therefore safe operating pressure...

BTW, I would get a rebuild kit for the valve and replace that diaphragm in pressure balancing valve once you rectify your redneck water hookup... If it is pulsing that much every time you use it, it is not long to remain intact and your hot water will over power its way into the lower pressure well fed cold water pipe eventually whenever you open a tap fed by the well through the busted pressure balancing valve when it self destructs...