Air lock i think

[scotthud]

Hi all first post so be nice, I took a radiator off to flush it as it would not work / bleed. I put it back on and since then the radiators would not get warm, ive bled them all about 20 times each over the last two days, ive tried draining the system but the header tank remains full (ive turned off the refill valve and hooked the ballcock up just in case) i have managed to back fill the header tank or at least get water to come out of the overflow from a downstairs radiator connected to a hose and the outside tap, but still the header tank wont fill back to the radiators or empty. Ive just been around them all and drained and bled them again or at least the ones that could be drained, the upstairs didn't have any water in them. The system appears to be blocked somewhere although when backfeeding it gets water through? ive vented the tank (well i opened the bleed valve but nothing came out) Ive also got two radiators that still have water in as i cant turn the drain valve on one as it appears rounded and the other wont accept the bleed key (wont fit in the hole to valve)? ive tried loosening the screw but they are very stiff and im afraid to bend the pipework connecting them to the radiator and causing a leak / further issues.

Ive been around the system again this morning (07/04/24) and bled the radiators, all the downstairs ones had air in the system and after bleeding the first two (furthest away ones) i heard a little gurgling and water in the pipes, but nothing apart from air came out, again the one downstairs radiator had water in it (as mentioned above) upstairs nothing came out of any of the radiators, no air or water.

Any help much appreciated.

 

[Ray1000]

While waiting for a more informed reply ... have you turned the circulating pump up to full speed
Ray

 

[scotthud]

While waiting for a more informed reply ... have you turned the circulating pump up to full speed
Ray

Yes ive turned the pump onto all speeds , its a grundfors alpha 2

 

[oldbuffer]

Sounds as if the pipework between the Feed and Expansion (F&E) tank and the system is blocked. Try running a magnet over the pipework starting at the outlet from the F&E and working down. If it seems to stick in places, that is likely where the blockage is.

 

[scotthud]

Sounds as if the pipework between the Feed and Expansion (F&E) tank and the system is blocked. Try running a magnet over the pipework starting at the outlet from the F&E and working down. If it seems to stick in places, that is likely where the blockage is.

Cheers ill give it a go, how come it back filled though?

 

[scotthud]

this baffles me, if the header tank is staying full (ballcock held up so as not to refill) how come when i open this drain valve and the bleed valve i get water out from the downstairs radiators but nothing from the upstairs ones? and is this the drain valve i have one of theses valves on every radiator, i dont have any other type of drain on any of the radiators?

 

[terryplumb]

As oldbuffer advised above ,there is a blockage between the f &e cistern and the feed into the system . There is some water in the system in downstairs rads , probably as a result of you backfilling the system.

 

[scotthud]

update after reading other forums on here, i did the magnet trick and found that it stuck to the pipes just near the three way valve (i think thats what its called)

 

[terryplumb]

That isn't a 3 way valve its an air separator ,and it's blocked and the cause of your problem.

 

[scotthud]

That isn't a 3 way valve its an air separator ,and it's blocked and the cause of your problem.

my mistake, ok since lunch i left everything and then went around downstairs radiators, 3 had air coming out when bled others had nothing, i also then opened the drain valve at the bottom of each radiator and got approx 1 tub of water out, could it be that some little amounts are getting through? ive got the ballcock strapped up and feeder valve shut and the header tank does seem to be going down slowly?

 

[Johntheo5]

Can you post a better photo of the air separator showing the pipework.

 

[terryplumb]

my mistake, ok since lunch i left everything and then went around downstairs radiators, 3 had air coming out when bled others had nothing, i also then opened the drain valve at the bottom of each radiator and got approx 1 tub of water out, could it be that some little amounts are getting through? ive got the ballcock strapped up and feeder valve shut and the header tank does seem to be going down slowly?

View attachment 339508

Quite possibly that a small amount of water is getting through if the pipework isn't blocked solid. Nevertheless ,you still need to cut out the blockage.

 

[scotthud]

Can you post a better photo of the air separator showing the pipework.

hope these are ok

 

[scotthud]

Quite possibly that a small amount of water is getting through if the pipework isn't blocked solid. Nevertheless ,you still need to cut out the blockage.

Well that's a job for the Pro's, what sort of damage would i be looking at roughly would you say.

 

[Johntheo5]

hope these are ok

You backfilled it through the vent earlier on, tie up the ballcock and bail out 4 or 5 litres of water from the F&E cistern, connect up the hose again, stand by the cistern and get someone to just crack open the mains, as soon as water issues from the vent; hold your hand over it, the pressure might just clear the blockage in the cold feed, you will see the water filling the cistern, hopefully, might get you going, at least temporarily.