|Posted by Deb on July 25, 2003 at 17:12:00:|
|In response to Re: Watts Water Pressure Reducer|
: It is the Watts 25AUB By Pass Model. The description says, "Allows water to escape back into the supply main line before it can affect the relief valve". Is it still true I don't nned the expansion tank if I get this PRV?
: : : I was told that this reducer has a built in expansion valve and I didn't need a water expansion tank. Is this true?
: : If this simply has a bypass, then you probably need an expansion tank. I have never seen a PRV with a built in expansion valve (where does the expanded water go?). What brand and model is this?
If the pressure on the main supply is higher than the pressure release setting on the T & P valve, it is going to blow. I plumb in areas where the incoming pressure is 180 psi or greater. The T & P pressure release is 150 psi. As the pressure increases, the increase pressure is going to try to get back into the main water system via the bypass, but it cannot, because the pressure out there is 180. When it hits 150 and it can't bypass back into the system, the T & P will release.