Pressure vessels

[GasmanxxxR1]

When checking the charge of an expansion vessel is it okay to do with the boiler/system/cylinder full or does it need to be emptied.

Does an unvented cylinder need to be completly empty of hot water before re-pressurising?

I know these are basic questions, I have man flu and two kids screaming, head is pounding just cant think straight.

Cheers Fellas

 

[Killy Bing]

my view is it needs an open end so when you recharge the vessel it pushes water out.

unvented I turn off the mains in a open the hottaps and recharge.

 

[Chalked]

Empty. as you need to check the expansion vessel air pressure. Not the pressure acting on it by water.

 

[GasmanxxxR1]

my view is it needs an open end so when you recharge the vessel it pushes water out.

unvented I turn off the mains in a open the hottaps and recharge.

Thanks Billy, thats what i currently do, had customer in my ear saying 'last guy didnt do that'

 

[GasmanxxxR1]

Empty. as you need to check the expansion vessel air pressure. Not the pressure acting on it by water.

Would you shut of mains and drain the cylinder from DOC or would you turn of mains and undo hot tap to release 'system pressure'

Cheers

 

[Killy Bing]

Empty. as you need to check the expansion vessel air pressure. Not the pressure acting on it by water.

you only need an open end to relieve the pressure of the system to it ?
then you're measuring the vessels pressure?

 

[GasmanxxxR1]

What about pumping it back up?

 

[Chalked]

Just mains then open hot tap. As long as the cylinder was piped up correctly, this wil release pressure.
check pipework is correct! I have come across the vessel fitted before prv!

 

[Killy Bing]

youll be pumping with an open end, water is just going to splutter out of that as the vessel empties.
the issue comes with the diaphragm splitting when you're pumping against a sealed system as water does not compress.

 

[GasmanxxxR1]

Cheers guys, knew i was doing it right

 

[gassafe]

Get a long regin pressure foot pump too... It takes a lot of pumping to do the 3 bar cylinder ones!

 

[EPH]

Get a long regin pressure foot pump too... It takes a lot of pumping to do the 3 bar cylinder ones!