Expansion Vessel losing all pressure in hours?

[dan_the_plumber]

I've looked that up. An interesting concept. Although in my opinion wouldn't lead to much water being on air side. Maybe a bit but, generally if you've got more than a squirt coming out the Shraeder then your vessels knackered.

 

[Harvest Fields]

Also not ever being called back to an address is not evidence that your original repair was successful, in fact you may find it to be quite the opposite.[/QUOTE]
It is when I have been back to the same property on consecutive years after the repair to service the boiler.

 

[oilmark]

Never heard of that before. How does the moisture get into the air side of the vessel to begin with?

When they are recharged with a foot pump water goes in with the air depending on humidity. Think they're filled with nitrogen from new and I have read that if nitrogen leaks out then replace vessel?!?
I have always pumped them back up and not had problems.