110 psi?

Good afternoon. I have noticed lately that my house pressure creaps up to approx 110 psi (per a lazy arm gauge on a faucet). The Pressure Regulator (PR) located where the water pipe enters the house is set for approx 55 psi as is the thermal expansion tank. I recently flushed out the PR out by removing the 2 plugs, screen, etc and running some flow through it. With the water feed turned off (no pressure) checked the expansion tank, found no water inside it and re-set it to 55. When I turn on a faucet in the house I get a burst of high pressure then it tapers off to approx 55. The gauge I have on a faucet generally reads 60 but the lazy arm almost always indicates the pressure has crept up to 110 (+/-). I checked the pressure relief valve (PRV) on the heater and turned it on/off a few time to make sure it is operating and get flow when open, no flow when closed. The heater is a 50 gal gas fired one, the expansion tank is a Wilkins WXTP-8A. I give up, any thoughts as to what may be the problem will be most appreciated.

If the PRV is older than fifteen years, I would question whether the diaphragm is still good.

110

If it creeps up overnight, or even when no hot water was used, then the pressure reducing valve has gone South.

Good morning. I went ahead a replaced the guts of the Pressure Regulating Valve (easier to use the same body and just replace the interior components) and that did the trick. The valve, Wilk1ns 600, is only 3-4 years old however and this seems to be the life span as I have done this before, a couple of times actually. Any ideas as to why the short life span or is this normal? Thanks again for the input, most appreciated...

If it's averaging 110, it could be peaking a lot higher overnight. What is th emax pressure range spec'ed for that valve? You may be exceeding it. In this case, use a different one, or put two in series so the drop across each is lower.

The system was peaking o/a 110 psi per the tattle-tail arm on the hose bib meter. The valve is rated for 300 psi max. Since I changed the valve's components out it now peaks at 70 psi (+/-) and settles out at 55 psi generally. My question now is should I continue to adjust the valve to keep the peak(s) below 60 psi or is the occasional rise to be expected (not sure as to the desired goal to be honest, regulating the psi peaks or finding an average working psi)? My other thought is how much of these minor variations should the expansion tank be absorbing? Thanks again for your feedback...

Vinagre said:

Good morning. I went ahead a replaced the guts of the Pressure Regulating Valve (easier to use the same body and just replace the interior components) and that did the trick. The valve, Wilk1ns 600, is only 3-4 years old however and this seems to be the life span as I have done this before, a couple of times actually. Any ideas as to why the short life span or is this normal? Thanks again for the input, most appreciated...

Click to expand...

Because it is a Wilkins.


Cheapest PRV on the market. I only install Watts because they have a better longevity reputation.

It's my understanding that a well functioning PRV should keep fairly constant output pressure and not exhibit the peaks you are indicating unless the input exceeded the ratings.

A properly sized and installed and setup expansion tank should keep the pressure from rising.