Boiler pressure relief valve slow leak
#1
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Hi,
I hope that someone could give me advice, I shut off my gas boiler and am trying to replace my 30 psi pressure relief valve with watts part 354 but is it appears that the new one is slightly different than my old one. The new one has a nut below it and the old valve has the nut on the iron pipe. Do I remove the old nut off the old pipe or take the nut off the new PRV? The reason that I am replacing it is because the PRV leaks slowly maybe by the drip. In the picture, the old one is on the right. Thanks for your help.
I hope that someone could give me advice, I shut off my gas boiler and am trying to replace my 30 psi pressure relief valve with watts part 354 but is it appears that the new one is slightly different than my old one. The new one has a nut below it and the old valve has the nut on the iron pipe. Do I remove the old nut off the old pipe or take the nut off the new PRV? The reason that I am replacing it is because the PRV leaks slowly maybe by the drip. In the picture, the old one is on the right. Thanks for your help.

Last edited by NJT; 03-21-15 at 11:41 AM.
#3
Vinny, if you haven't already, please read this:
http://www.doityourself.com/forum/bo...sion-tank.html
It's very possible that the valve is weeping as a SYMPTOM, rather than the CAUSE.
Please take a picture of where you removed the valve from.
http://www.doityourself.com/forum/bo...sion-tank.html
It's very possible that the valve is weeping as a SYMPTOM, rather than the CAUSE.
Please take a picture of where you removed the valve from.
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more pics
Hi all, thanks for the replies.
I agree to keep the new valve intact, thanks. So the next part is what to do about the pipe. Here are 2 more pics. Thanks for your help. I did read that post and I will check the expansion tank soon.
I agree to keep the new valve intact, thanks. So the next part is what to do about the pipe. Here are 2 more pics. Thanks for your help. I did read that post and I will check the expansion tank soon.
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The system usually maintains a pressure of 12-15 psi. The PRV leaks even at 0 PSI. The problem that I am having is that the nut will not come off the iron pipe. I think this PRV was probably installed in 1985. I am using a 14" pipe wrench and there is very little room to put a pipe on the wrench handle for leverage. Thanks for your help.
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Use two hammers a large one as the anvil and a smaller one to strike the nut opposite the anvil ,then move anvil around 90 degrees and repeat works every time to disassemble BI pipe .
#9
Then do what you need to do to fix it..remove brass piece from new PRV.
Or remove pipe to boiler and replace with new.
Or get bigger wrenches..
Probably need other work too on the boiler. I see that air vent looks shot and should be replaced....
Or remove pipe to boiler and replace with new.
Or get bigger wrenches..
Probably need other work too on the boiler. I see that air vent looks shot and should be replaced....
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It took 2 of us to loosen the nut from the pipe. One to hold the iron pipe steady with an adjustable pliers and both of us putting pressure on the nut with the 14 in pipe wrench. Unbelievable when it came loose.
I have a quick question regarding that rusted air vent, it bent a bit as we were trying to break free the nut. Does that air vent just screw off by hand? It did not seem to loosen. We already have another air vent in the system, so this one is always closed.
I have a quick question regarding that rusted air vent, it bent a bit as we were trying to break free the nut. Does that air vent just screw off by hand? It did not seem to loosen. We already have another air vent in the system, so this one is always closed.
Last edited by vinny121; 03-22-15 at 04:45 PM.