creating a vacuum - bunging feed and expanison tank

[wilhelm]

Ive bunged for rad valves, but never for 3 ports. So if it works...

watch this space .......

 

[nickso]

Ive bunged for rad valves, but never for 3 ports. So if it works...

watch this space .......

just listen for he glugging and dont leave it open while you got for a **** or a cup of tea.

 

[wilhelm]

No problem, I drink coffee.

 

[nickso]

No problem, I drink coffee.

that was the **** i was talking about.

 

[WDIK]

germans bearing carrots

 

[scatmanjohn]

I use bungs, but when i am in the mood i love the good old "snatch"

 

[namsag]

With scatman on that nothing beats a good snatch. . Mac on back to front and in you go.
Serious thou have changed loads of 3 ports on bungs ,anti gravity valves, have blown joints on upto 22mm on them, changed cylinders and also changed boilers . 95% success rate
As someone has already said its best to bleed system first as this does help and people forget to do it. The soft bungs are far better than the hard ribbed ones as they fit into tank connectors better

 

[liverpoolboy]

interesting post-I too have hears of this but never tried it yet, sounds a lot easier than draining and refilling!

Why would bleeding the rads first help to create the vacuum though? And why is it important to listen out for the gurgling? Is this to let you know water is on the way?!

I believe most tank connectors usually are slined, if by that you mean have a small indent on either side of then?? WHy would non splined tank connectors not work?

When I next go to B & Q (my fav store)!!! I might look for some as they sound really useful and surely are not that expensive?

 

[nickso]

When I next go to B & Q (my fav store)!!! I might look for some as they sound really useful and surely are not that expensive?

save yourself some money, go to screwfix. owned by the same company but they are cheaper. handcrafting them from gold would be cheaper than B&Q.

 

[ollski]

If the connector is splined just wrap a load of ptfe around it and it will hold. Just make sure the feed doesn't suck the ptfe tape off and into the system when you take the bung out though.

My own failure rate on bungs must be less than 1% as I can't remember the last time I had a job which didn't hold. Sometimes feels like failure is on its way when you fill a 3 gallon bucket but it always holds sooner or later.

 

[liverpoolboy]

i know screwfix is good - but b & q aren't that expensive really...!!

 

[superdupergasman]

Always use bungs..... cone type and expanding ones.... I NEVER drain anything....also I never relieve the pressure using the drain...always use the coupling of what I want to change..... for 3 ports I close a pump valve and that makes it into only 2 open ends.

IMHO they are better than 95% I would say 99.9% will bung if you are brave enough and have a bucket or nappy under it.... and I have never brought down a ceiling....YET....

Cant remember that last time I drained a system.

 

[liverpoolboy]

and it saves you needing to an an inhibitor again. i suppose you only need to drain if you want to change pipework... otherwise sounds good to me. When I changed a rad valve using 2 bungs i closed the lockshield drained the rad, bled it as i was doing it, and no water at all came from the open rad valve - it was really good.

if i ever need to change a pump/mot valve then i will use them again (some proper ones this time though that will last)!

I suppose though if you are changina pump/mo alve you do need to bleed the pump/rads before as it will be 2 open ends and will need more pressure reduced first?

I don't know what these splined tank connectors are though to be honest , I just used expanding plastic/rubber plugs and they worked fine!!...

 

[nickso]

i know screwfix is good - but b & q aren't that expensive really...!!

yes they are actually.

some stuff is half price in screwfix compared to b&q.

 

[lagunaglen]

Have used bungs dozens of times and changed pumps ,3 port valves, rads etc, dont use a bung on the expansion pipe, i use a speedfit stop-end instead as it does the same job but wont ever drop off the end.Sometimes need to clean end of pipe up first or slice a little bit off the end if its not round but never ever had a failure.