Help unscrewing rusty expansion tank

[nanotech1112]

Hi all,

I'm trying to replace an old, rusted-thru water expansion tank, but I can't get it to budge. Should I try using a propane torch to loosen the connection?

Also, not sure why water's still dripping from the bottom of the tank, even after I shut off the water inlet valve.

 

[Caduceus]

Try giving it a few doses of PB blaster or other rust-buster over the course of a few days. Make sure to back up on the other fitting with a wrench, (apply the opposite force used to remove expansion tank.) If the bladder is broken, the tank will be filled with water and heavy. Also be sure that the isolation valve shuts off all of the way before attempting to remove the thermal expansion tank.