|
|
Post by scousep on Nov 27, 2020 6:29:55 GMT
Hi guys
when draining a gravity fed heating sYstem what is your preferred method
1 turn off mains
2 tie up ball cock / iso valve on tank
3 bung tank
I was watching a plumber parts video where he switched off the cold inlet at the gate valve of the cylinder (Indirect) but this has confused me because I thought this would just Stop the supply at the hot water taps? He’s an expert so I must be misunderstood on this point. does this cold feed pipe tee into the heating flow maybe ?
also what is best method to ensure you avoid air locks when filling system. Or if you do get airlock how to do you locate it and fix it ??
thanks in advance
|
|
|
|
Post by dickpuller on Nov 27, 2020 7:37:20 GMT
Bung it matey, if you don’t want air locks or to lose all system water inhibitor etc.
What are you doing? Replacing a radiator?
|
|
|
|
Post by scousep on Nov 27, 2020 7:55:52 GMT
Cheers replacing dodgy lock shield....
what size bung or just buy a cone one from merchants
|
|
|
|
Post by dickpuller on Nov 27, 2020 10:50:06 GMT
Cheers replacing dodgy lock shield.... what size bung or just buy a cone one from merchants Depends on the size of the Expansion pipe & the type of CF tank connector👍👍 |
|
|
|
Post by tomplum on Nov 27, 2020 13:40:01 GMT
Hi scouseP, bunging is best left to the more experienced because, there is always going to be water in the pipe, and there are so many options, we could be discussing this for weeks, can you show me a picture of the valve and whether its on a upstairs rad or downstairs rad and I will tell you which way i would do it for the easiest and less airlocking way, Dick may do it a differant way and others would disagree, plumberpants is a good guy but He likes to talk a lot, never trust a plumber who talks a lot, You know the script, there are those who talk the talk and those who walk the walk,  I come on here most days, so I will reply and help you,  |
|
|
|
Post by cylinderfella on Nov 30, 2020 22:52:19 GMT
When the wife's away I turn off the mains and drain down because I'm lazy and don't want to get the ladder and go up into the dusty zone!! All the options you gave are fine, but don't bung unless you're confident it will hold, you don't want a water feature spewing out from the pipe of the lock shield you're changing if the bung fails. You could get a length of hose pipe ready just in case and smack it on the pipe if the bung fails and send the flow outside. |
|
|
|
Post by crowsfoot on Dec 1, 2020 7:25:36 GMT
It's always badnews when the ballvalves stuck though and you have to get the steps out and end up entering the dusty zone  . It happened to me once with a nest of buzzing wasps up there, no way was I going up! I backfilled the system with the brickie keeping his eye on the hose whilst I nipped round venting - no air locks with a mains fill and when the overflow started to run I knew the system was full, ways and means eh? Tappy, |
|
|
|
Post by cylinderfella on Dec 1, 2020 21:34:07 GMT
Brilliant ingenuity!
|
|
.