Radiators not heating up

[br jones]

Nope. Those 4 radiators still dont work even after continued bleeding.. My only thought is it could maybe be a blockage in a pipe, perhaps the return as the radiators seem to have preassure at the bleeds. Curious problem.

you said previuosly said they have never got hot ?

 

[Lincsman]

Nope. Those 4 radiators still dont work even after continued bleeding.. My only thought is it could maybe be a blockage in a pipe, perhaps the return as the radiators seem to have preassure at the bleeds. Curious problem.

I would still take one off and flush, while it's off you can assess the flow to each end of the rad to check the tap operation. You haven't swapped the trv at some point and fitted a one way flow type.. and some fancy radiators only work with flow one way.

 

[Jsmith2211]

you said previuosly said they have never got hot ?

They did a long time ago, but they haven't worked for a while. Several years. Just never got around to trying to fix those ones till now, when half of the rest of them stopped working too I thought I'd better try to sort it out!

 

[Alchad]

Do you know if the system has ever had corrosion inhibitor? Even if it has I’d try adding central heating cleaner and giving it a good flush - maybe do it twice given the problems you’ve got.

 

[Oliveau]

you said previuosly said they have never got hot ?

Might just be worth looking at the valve at the return end of the rad. Usually an Allen type screw under the cap, so open & shut it a few times as it may be blocked with crud.

 

[Farmer_Joe]

Good chance the Pressure Vessel is knackered ( test by dropping the system pressure to 0 then put a pressure gauge on the expansion vessel, should be 0.8 bar, if water come out of the schraeder valve, its shot, if not, pump back up to 0.8 bar ) if so, then system water is most probably going out of the pipe to outside from the pressure relief valve, put a balloon on the pipe to prove this is the way it's disappearing.

if you tap the vessel it should not sound dull if it does its full of water, they should sort of 'ring' if theres still air in there,

some ive had are brilliant for years most are, odd one is crap and the air gets out

1.5 bar should be adequate 3 bar is to much as adpet andy says most sealed central heating systems have a pressure release valve ( or should have ) which is 3 bar.