Expansion tanks and purging

Ken C.

Hello,

For hot water systems with the old-style steel thermal expansion tanks in the joists:

1) How do you tell if the tank is waterlogged?

2) How do you correct this condition?

3) Do you have to do anything different when purging a hot water system with one of these tanks (as opposed to a newer bladder type expansion tank)?

John@Reliable_5

#1. If water is leaking from PRV when unit is running and psi seems to go up quick might be waterlogged and last tap it top of tank should sound different(air) #2. Shut off valve between boiler/piping and drain tank completely! if you don't drain til m/t thier won't be enough air in tank when you refill it, causing waterlog even quicker. #3. I shut off valve as in #2 and purge system then open valve back up. John@Reliable