kk
New Member
I have a System 2000 boiler which has a seprate hot water storage tank which is heated by a heat exchanger. Everything worked fine for over a year after it was installed, but lately it has started over-pressuring, which causes the T&P valve to open. I put a gauge on the tank to verify what I already knew - yes, it's really over pressuring. The telltale sign was the brief high pressure occasionally when turning on a faucet.
In looking at the system, there is no expansion tank on the hot water side, and the only thing inline is the PRV at the water meter, which is a Watts 25AUB. This PRV is supposed to have an internal bypass if the internal pressure exceeds the street pressure, so it would seem it should prevent the 150-160psi I'm seeing.
Finally my questions:
1. Could the street pressure really be greater than 150psi? If it was, the bypass would not do anything and my system would overpressure. I called the water company but they only had a really old reading of 100psi for my neighborhood. Not sure how good that number is.
2. Could the bypass in the PRV be stuck? It appears from the drawings it's a spring loaded ball of some sort. I think the PRV was installed about 11-12 years ago.
I hate to put in an expansion tank if the problem is really somewhere else, and I hate to replace the PRV if I really need an expansion tank.
Any input would be appreciated!
-kk
In looking at the system, there is no expansion tank on the hot water side, and the only thing inline is the PRV at the water meter, which is a Watts 25AUB. This PRV is supposed to have an internal bypass if the internal pressure exceeds the street pressure, so it would seem it should prevent the 150-160psi I'm seeing.
Finally my questions:
1. Could the street pressure really be greater than 150psi? If it was, the bypass would not do anything and my system would overpressure. I called the water company but they only had a really old reading of 100psi for my neighborhood. Not sure how good that number is.
2. Could the bypass in the PRV be stuck? It appears from the drawings it's a spring loaded ball of some sort. I think the PRV was installed about 11-12 years ago.
I hate to put in an expansion tank if the problem is really somewhere else, and I hate to replace the PRV if I really need an expansion tank.
Any input would be appreciated!
-kk