Pressure Valve Leaking

grodgers11

I'll start by saying I'm no expert so apologies in advance if any of my terminology is off.

About a month ago, I went down in the basement and found a fair amount of water on the ground and the pressure relief valve leaking. We had someone come by to take a look and they determined the expansion tank needed to be replaced, so they replaced that and the pressure relief valve. This seemed to fix the issue for a month or so, and then a couple days ago I noticed a significant amount of water leaking out of the pressure relief valve again. And it wasn't just dripping, it was a fairly steady stream of water flowing out with our bucket filling every couple hours. The pressure was high, around 30 PSI. The dripping slowed down some when I turned the heat down, but still leaking.

The same person came back to take another look. He replaced the pressure relief valve again saying it may be a faulty valve, but it could also be a hole in the coil in the hot water tank. He got the pressure back down to 15 PSI and turned off the water flow from the boiler. He said this would isolate the issue, and the only way water could get to the pressure relief valve would be through the hot water tank, so if the PSI went above 15 and water leaked again, the issue had to be a hole in the coil in the hot water talk, and the fix for this is a very expensive new tank. He tried running the hot water to replicate the issue but wasn't seeing any leaks. However, a few hours after he left, I turned the heat back up and ran the dishwasher, and the pressure was back up well above 15 PSI and the valve was leaking again.

Before I move forward with replacing the hot water tank, I figured I'd ask on here to see if there are any other issues that may be causing the leak? Thanks!!

Jamie Hall

Before you spend much dollars, double check.

Turn off the heat (spring is coming). find the valve which shots off the line from the domestic water supply to the heating side of the boiler Close it. Find the drain on the boiler, open that and drop the pressure to 15 psi. Close it. Let the whole thing sit for a few hours at least. Any change in the water pressure? If so, the pressure reducing valve feeding the boiler may be leaking by. To double check, reopen the line from the domestic water supply which you had closed. Recheck. Does the pressure rise? If so, bingo -- the pressure reducing valve on the connection from the domestic water to the boiler is faulty and needs replacement.

Now if the above didn't pan out, again -- with the heat off -- close the valve which feeds domestic water to the water heater -- not any on the connection to the boiler. Check the boiler pressure and set at 15 psi. Let it sit for a while. Is the pressure constant? If so, now open the valve for the domestic hot water to the hot water heater. What happens?