Diaphragm Expansion Tank Query

[tankman104c]

I have my own water supply from a bore hole and submersible pump feeding a Cimm expansion tank which is situated in a shed.
Can I turn the power to the pump off and then release all the water pressure by opening a tap without doing any damage to the diaphragm in the tank or do I have to release the air pressure in the tank as well?
There are 2 reasons for the question. Firstly, I have water leaking from under the cottage which could be ground water as we have had an awful lot of rain recently and I need to prove it's not a burst pipe!
Secondly, I am replacing the shed in which the tank lives and I need to move it a small amount but would prefer to move it when it's not pressurised.
Thanks for any comments.
Russ

 

[mysteryman]

As far as I know you can do it as you suggest. They are supplied pre-pressurised anyway. Further, it will drive the water out if you do it as you say.