Bunging a tank - Rad valve changing tools

[allenvb]

Dear all,
Can anyone help, I have a set of the these bungs that are used to block up the vent and tank outlet of the CH system, but it does not seem to work, it does not slow down the flow at all.

Is it just a case of 'bunging' up the pipes or should there be something else that is done to stop the flow ( I am only working on one open pipe at a time)

Thanks in advance

V

 

[ollski]

Sometimes can take a gallon or more of water before the flow stops. Sometimes it doesn't. Make sure you have no auomatic air vents open

 

[Gasguru]

Make sure you bleed any air from the system...otherwise it will expand as you drain taking much longer for the water to stop flowing.

 

[JohnD]

i have found the bungs don't seal well in plastic tank connectors.

I am not a plumber.

 

[GPlumb]

i make bungs out of denso tape, works fine for me.

 

[Paul Barker]

Modern trend of boiler manufacturers is to use aav without a sealing cap so seal those with closure plate tape (remember to remove)

Great tip about the denso so it's not just for flavouring your sandwitches?

I changed two pump valves yesterday this way (the guy who changed the pump didn't do the full job properly or hang around to make sure!). It did take a full bucket of water to make it work, but as usual it did work. it's always worthwhile in such scenarios being ready for snatching it anyway.

For instance the day before I changed a trv it never was going to hang fully but I snatched it anyway, then found that my replacement trv was different olive position so off again cut olive on again with new olive. With the decorators tray underneath and a piece of card stuck round the pipe with closure plate tape not a single drop went on the carpet. But that is not snatching at full pressure just at the pressure you get when for some reason which might take too liong to investigate it isn't hanging fully. It would have been the aav in this case but the boiler was in a bathroom cupboard boxed in by tampons bras talc and knickers so I sort of kept out of there, after a quick look at the sluborn sat in front of loose women I didn't have the heart to ask her to move her stuff out the way the poor luv.