Expansion Tank

AL_5

Hi there.

I need some general information on expansion tanks.

In a hot water system, does the water from the expansion tank ever go back into the boiler?

Is there a special valve that purges water from the tank when the expansion tank is full?

What happens if the tank is full but it is unable to purge or release water to make room for expansion?

Thanks in advance to all those that respond.

Frank_17

xtanks

what type of x-tank? solid steel, or bladder?
the answer to two of your questions is the same for both type. yes, the water can get back to the boiler, from heating and expanding, the water will travel in and out of the tank and back into the piping, If the xtank is waterlogged on either type, when the water expands from heat,if sized correctly, will blow off thru the relief valve on the boiler if it exceeds 30# of presssure. the one piece steel tanks usually have a manual drain/purge valve IF PIPED CORRECTLY.

[Deleted User]

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