pressure relief valve leaks

secutanudu · 05-09-2011, 08:45 AM

I think modern indirect water heaters are "tank within a tank" design. Inner tank holds domestic drinking water, under pressure. Outer tank holds boiler water.

If there's a leak in the inner tank, the problem Daniel H. had could exist in your system.

how · 05-09-2011, 12:19 PM

Isolating your heating boiler feed lines to your hotwater tank will tell you if the hot water tank is the problem. Turn the power off to the boiler /turn off the gate valves on the two lines going to your tank/ reduce the psi in the boiler to 20 psi and see if that pressure remains stable. If the boiler is cool and the psi doesn't creep back up you've got a bad tank coil.

If you don't have gate valves on both lines going to your hot water tank then..turn off the power to the boiler/ turn off the domestic cold water gate valve feed line to the hot water tank/ open a hot water tap in the house/ reduce the boiler psi to 20 and watch if it creeps back up.

I tried to post this a few times yesterday but it disapeared twice and I gave up.

Cheers

f9 flier · 06-13-2011, 10:54 AM

I have tried just about everything I can think of and also what's been suggested and the pressure relief valve continues to leak. I have bled the pressure down to 20 psi and as long as the boiler doesn't run it stays constant. As soon as the boiler starts up the pressure begins to increase until it reaches 30 psi and then it drips. Once the boiler shuts off it will drop to about 28 psi and remain constant.
Any more ideas?

Ishmael · 06-13-2011, 11:14 AM

Quote:

Originally Posted by f9 flier

I have tried just about everything I can think of and also what's been suggested and the pressure relief valve continues to leak. I have bled the pressure down to 20 psi and as long as the boiler doesn't run it stays constant. As soon as the boiler starts up the pressure begins to increase until it reaches 30 psi and then it drips. Once the boiler shuts off it will drop to about 28 psi and remain constant.
Any more ideas?

I came across this once - very frustrating. I eventually found out that the bottom port of the spirovent/air scoop where the expansion tank gets screwed-in was clogged with sediment - basically forming a dam such that the expansion tank was rendered useless. I think someone must've used copious amounts of boiler seal liquid to "fix" a leak somewhere in the system.

Drain the system, remove the expansion tank and check that threaded tapping. Make sure it isn't clogged with sediment, scale or "other" (e.g. - coagulated boiler seal).

f9 flier · 06-14-2011, 09:18 AM

Thanks guys I really appreciate the help.

Ishmael · 06-14-2011, 04:58 PM

Quote:

Originally Posted by f9 flier

Thanks guys I really appreciate the help.

Does this mean you've figured it out?

f9 flier · 06-14-2011, 07:55 PM

Yes I believe it's actually fixed. The domestic hot water heater was the main culprit but the sediment was the last piece to the puzzle. Thanks again for all your help. Couldn't have done it without you guys

05-09-2011, 08:45 AM	#16
secutanudu Just call me Andrew Join Date: Mar 2009 Location: Albany, NY Posts: 2,247	pressure relief valve leaks I think modern indirect water heaters are "tank within a tank" design. Inner tank holds domestic drinking water, under pressure. Outer tank holds boiler water. If there's a leak in the inner tank, the problem Daniel H. had could exist in your system. __________________ Andrew

05-09-2011, 12:19 PM	#17
how Member Join Date: Feb 2011 Location: Vancouver BC Posts: 1,416	pressure relief valve leaks Isolating your heating boiler feed lines to your hotwater tank will tell you if the hot water tank is the problem. Turn the power off to the boiler /turn off the gate valves on the two lines going to your tank/ reduce the psi in the boiler to 20 psi and see if that pressure remains stable. If the boiler is cool and the psi doesn't creep back up you've got a bad tank coil. If you don't have gate valves on both lines going to your hot water tank then..turn off the power to the boiler/ turn off the domestic cold water gate valve feed line to the hot water tank/ open a hot water tap in the house/ reduce the boiler psi to 20 and watch if it creeps back up. I tried to post this a few times yesterday but it disapeared twice and I gave up. Cheers

06-13-2011, 10:54 AM	#18
f9 flier Newbie Join Date: Apr 2011 Posts: 9	pressure relief valve leaks I have tried just about everything I can think of and also what's been suggested and the pressure relief valve continues to leak. I have bled the pressure down to 20 psi and as long as the boiler doesn't run it stays constant. As soon as the boiler starts up the pressure begins to increase until it reaches 30 psi and then it drips. Once the boiler shuts off it will drop to about 28 psi and remain constant. Any more ideas?

06-14-2011, 09:18 AM	#20
f9 flier Newbie Join Date: Apr 2011 Posts: 9	pressure relief valve leaks Thanks guys I really appreciate the help.

06-14-2011, 07:55 PM	#22
f9 flier Newbie Join Date: Apr 2011 Posts: 9	pressure relief valve leaks Yes I believe it's actually fixed. The domestic hot water heater was the main culprit but the sediment was the last piece to the puzzle. Thanks again for all your help. Couldn't have done it without you guys

pressure relief valve leaks