Do we still recharge expansion vessel with pump?

[John_]

Hi all, just wondering if it is still possible to recharge expansion vessel with hand pump on modern boilers? I swear I read somewhere it said that expansion vessel on modern boilers got special gas and not (or can't) be recharge. Just can't remember where I read this. Can someone clarify this? Thanks in advance. John

 

[chris watkins]

Vessel's come pre-charged with a rich Nitrogen gas charge (as it is an inert gas). All those that have a Schrader valve can be topped up with air using a foot or hand pump as required. All well & good but how much pressure do you put in & should the system be drained ??

 

[diamondgas]

Foot pump does the job providing you know how to keep the system at atmospheric 🙂

 

[phpaul]

Foot pump does the job providing you know how to keep the system at atmospheric 🙂

i find just puting ur gob round the valve and blowing like mad does the trick.:biggrin5:

 

[Plumberparts]

Always have the system drained so you get an accurate pressure reading on the schrader valve when pumping up again!

 

[SafeGasInstall]

i am going to try this

 

[diamondgas]

i find just puting ur gob round the valve and blowing like mad does the trick.:biggrin5:

Take a lot less time with a foot pump :rolleyes2:

 

[Alpha man]

Yep, still pumping!

 

[Roger Welton]

The best tool upgrade i made was from a foot pump to a regin one with a nice long hose.

 

[stokecity]

ive got go look at an expansion vessel tomorrow which i suspect has lost charge, when charging do u isolate flow return at boiler, drain boiler and make sure aav is open?

 

[chris watkins]

Yes you do.

 

[chris watkins]

what are you going to pump it up too ? how many bar & why ?

 

[John_]

Do you have to add any chemical into the system after charging? If so, how?

 

[diamondgas]

ive got go look at an expansion vessel tomorrow which i suspect has lost charge, when charging do u isolate flow return at boiler, drain boiler and make sure aav is open?

It all depends on which boiler as to whether i touch the iso's or not!! Usually if the EV's gone so has the PRV. I usually leaver that open and let it run till it stops, then as I pump up the EV, it allows the water to escape and keeps the system pressure atmospheric 🙂

 

[diamondgas]

Do you have to add any chemical into the system after charging? If so, how?

Not as a rule John_, there's minimal loss of water 🙂

 

[zeebeedee]

It all depends on which boiler as to whether i touch the iso's or not!! Usually if the EV's gone so has the PRV. I usually leaver that open and let it run till it stops, then as I pump up the EV, it allows the water to escape and keeps the system pressure atmospheric 🙂

Cdi's, 24i's spring to mind! Once and once only, it was on a balanced flue version as well nightmare to change!

 

[John_]

Vessel's come pre-charged with a rich Nitrogen gas charge (as it is an inert gas). All those that have a Schrader valve can be topped up with air using a foot or hand pump as required. All well & good but how much pressure do you put in & should the system be drained ??

With nitrogen charged vessels, I assume u have to change to a new EV if it's discharged?

 

[zeebeedee]

The only reason nitrogen is used is because it's an inert gas therefore it has no chemical reaction with anything, ie the rubber diaphragm, it basically prolongs the life of the vessel.

 

[southcoastboile]

I always recomend changing vessel and prv if its gone flat. I find if you recharge it a few months down the line it will loose air again. If its lost air than there must be a fault with the vessel surely? I never ever touch the valves under the boiler, just knock the pressure off and then recharge

 

[diamondgas]

I always recomend changing vessel and prv if its gone flat. I find if you recharge it a few months down the line it will loose air again. If its lost air than there must be a fault with the vessel surely? I never ever touch the valves under the boiler, just knock the pressure off and then recharge

I actually carry replacement schrader valves and a tool for removing them! Bought the different types at halfords, replaced 1 so far lol

 

[zeebeedee]

I actually carry replacement schrader valves and a tool for removing them! Bought the different types at halfords, replaced 1 so far lol

Whats the tool? Pm us a link please. They hard to change?

 

[diamondgas]

Cdi's, 24i's spring to mind! Once and once only, it was on a balanced flue version as well nightmare to change!

Yep for definite a nightmare to replace .... I've seen me solder a plug around the valve and fit an iso further down the pipe! The Isar valves are the same, don't touch them!

 

[zeebeedee]

Yep for definite a nightmare to replace .... I've seen me solder a plug around the valve and fit an iso further down the pipe! The Isar valves are the same, don't touch them!

Nice one I'll bear that in mind!

 

[diamondgas]

Whats the tool? Pm us a link please. They hard to change?

I'll see if I can hunt it down ... It's a kind of all in one thing that cleans the threads as well!! Might get a picture to you! The schrader's re small dumpy one's by-the-way not the long thin things 🙂

 

[diamondgas]

Schrader tool 🙂 Found it at Amazon here http://www.amazon.co.uk/dp/B004XVQ2...nd=7591005311023252701&hvpone=&hvptwo=&hvqmt=