amtrol model 30expansion tank

Mark7

The safety valve on my daughters gas boiler is weeping .I depressed the air valve on bottom of expansion tank, and got water to come out. The boiler pressure is at 12 #, I shut the water make up off and the return and supply valves off, lowered boiler to zero and  installed new tank.I emptied the old tank of water best I could, but there still sounded like water trapped in there.I pumped up the tank again, and got more water out. Is this tank shot, or is there something here I am not getting? The safety is still weeping, I suppose it is shot also. There was a lot of cruddy looking water when I drained the boiler to install the new tank, so I think there is a build-up of goo or something keeping it from seating all the way. We should of changed the valve as long as the system was shut down and isolated. But getting back to the tank. Should I throw it away, or might it still be good? I would let someone else have it if it could be used.Thanks for any advice or help.

Paul Pollets

Replace

The bladder is shot. Replace it.

Mark7

Thanks

I figured as much, but thought I would get another opinion. Never hurts to ask, right? Thanks again

RJ_4

tank

diaphram or commercial bladder style tanks, always make sure the air charge is correct before allowing water into tank,  should match system press.

Eric_32

very easy

to have several issues at the same time.



If water comes out the schrader valve on the expansion tank... it's junk, toss it.



Check the charge on the new tank before the system is pressurized.



If the Pressure relief valve has discharged, even slightly, toss it too, many times they won't seal up again.



AND finally, confirm the pressure gauge is good on the boiler by using a gauge that will screw on the boiler drain. I couldn't tell how many times they are broken as well.