Repressurise white expansion vessel

[Jennie]

Hi all,
I've got my G3 card. First time I've attempted to re-pressurise the white, expansion vessel above an unvented cylinder.
I first turned the water off, ran the taps to relieve the pressure. The vessel (it was flat). I managed to pump it up to 1.2bar with no issues. But then it was extremely hard to pump.
A plumber before me had the same issue. He'd also removed the vessel to do this.
My question: is it physically possibly to get to 3bar with a foot pump? Or should I use an electric tyre pump (such as is used on car tyres)?
Regardless, the customer needs a new vessel as it didn't hold the charge. But I'd be interested to know how you'd all repressurise it.
Jennie

 

[ShaunCorbs]

Sounds like the vessel has been over expanded due to it not having air in

time for a new vessel then

but to your question yes it’s doable around 5mins normally to do one

 

[SJB060685]

I used to do it with a foot/hand pump lol. You can buy mini handheld compressors built purposefully for this job, about £50. If you're doing this a lot definitely worth investing in.

 

[SimonG]

Regin stirrup pump with long hose.

 

[king of pipes]

Did you hold the pin down in the scharader valve bit like a rad air in water out ? Pressure in there should be 3 bar i always use a Regin strirup pump as above . Kop

 

[Stigster]

Another +1 for the stirrup pump with long hose. Makes it possible to charge vessels in all kinds of locations whilst keeping the stirrup pump on the floor. With my old pump sometimes I had to put the base of it against the wall in an airing cupboard and work the pump horizontally which is no fun at all on the bigger vessels.

 

[Last Plumber]

Yes it is difficult trying to do that with a foot pump by hand. As above, Stirrup pump, mini compressor or take it out and use foot pump. If it is left in situ, leave hot tap open whilst you inflate it.

 

[Stigster]

leave hot tap open whilst you inflate it.

Whilst OP was aware of this being necessary, I am amazed at the number of plumbers who do not know this or didn't remember to do it at least. If you think about what function the vessel is performing and how it is constructed it should be pretty obvious that you need to charge with zero pressure on the wet side but so many don't do this and end up undercharging the vessel.

 

[SJB060685]

Whilst OP was aware of this being necessary, I am amazed at the number of plumbers who do not know this or didn't remember to do it at least. If you think about what function the vessel is performing and how it is constructed it should be pretty obvious that you need to charge with zero pressure on the wet side but so many don't do this and end up undercharging the vessel.

Yes many still get it wrong and end up with a false reading.

 

[Jennie]

Those regin pumps look fantastic. Much better than my foot pump (also put against the wall, as I try to do it by hand). Thanks everyone for your advice.

 

[Liberty Cap]

OK, I have a similar problem here. I have cold water coming out of the overflow when boiler running. Nothing comes out the tundish. I spoke to a friendly plumber outside Screwfix and he suggested I open the hot taps and try pumping up the vessel. However it is not holding any pressure and when I turn the water back it it sounds like the vessel just fills up with water. I am not a plumber but figure that the vessel must have some kind of diaphragm inside.

Would mine be comprised if I can not get it to pressurize?
Can I change it my self (looks straight forward) or do I need a G3 card?
They come pre pressurized right?

 

[Liberty Cap]

Doh, just noted the original OP said there's didn't hold the charge and needed a new vessel.

Note to self: Read the question.

 

[Lou]

(Just bumping a few older threads, they will drop off what is new soon)

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