Blockage? Not sure.

[TheJay]

I recently replaced my radiator and TRV thinking that was the cause of our bedroom radiator not working.

I got the central heating system running correctly and all radiators in the house were heating up nicely except for the new radiator and TRV in our bedroom.

I have examined the pipework and can feel in the middle of two pieces of copper pipe where it changes from hot to cold. You would think this was a blockage, but when I tested the radiator bleed valve on the new radiator there was water coming out immediately which means that the radiator was able to fill with water in the first place and indicating this is not a problem with an air blockage.

Do you have any idea what this might be? This is really bugging me and it's getting cold at night..

I would be extremely grateful if you could please kindly share your thoughts on this with me.

 

[Stadan20]

Could still be a blockage in one pipe ,you will still get water through the bleed valve , try shutting ALL radiators down apart from this one , while the heating is on

 

[TheJay]

Thank you for your reply, are you thinking this will force the one radiator to work?

 

[Stadan20]

Well if an air lock this will force air into that radiator , or even if there is a slight blockage , what system do you have ?

 

[Stadan20]

Also are you sure the trv and lock shield are open ?

 

[TheJay]

I am using a combi boiler. I think it's worth trying..

 

[TheJay]

I have turned the other radiators off and I can feel that the heat has moved up the pipe. I will see in the morning whether it has improved but things aren't looking hopeful right now. It's worth mentioning that when the radiator was replaced, part of the copper pipe was replaced because there was a leak so there shouldn't be a blockage where it seems to change from too hot to touch to warm enough to sustain touch to plain cold.

 

[Stadan20]

Yes but there could still be a blockage in the return .... The side you are talking about will be the flow. If you can feel some heat from it , are you sure the lock shield valve is fully open ?

 

[Stadan20]

If trv and lock shield are open and rad hasn't started working within 10 mins of being on I would suggest putting the rest back on , also when this copper pipe was replaced , a valve wasn't fitted to the pipe work was it ?

 

[TheJay]

The pipe which goes from too hot to cold must be the feed to the radiator which isn't getting warm at the moment. Just to clarify specifically, the pipe which feeds the radiator is cold, it loses heat at least 3-5 feet away and there is definitely water (albeit cold) in the new radiator. I can see two pipes which run side by side and the return is cold. When then pipe was changed it was a straight forward swap with collars rather than valves to join it back up.

 

[TheJay]

I haven't tried adjusting the lockshield valve yet..

 

[Stadan20]

Make sure the lock shield is fully open first

 

[Agile]

If the lockshield valve is open then you need to do a bucket test 9 see FAQ ) to see if the flow from one side is restricted.

You should get at least 5 litres per minute flow from each side. That's about the flow from an average basin tap.

If this pipe is really blocked can you get a straight line access to it to feed in a spiral wire pipe unblocker?

Tony

 

[TheJay]

Thank you for your suggestions, it seems that the lockshield was completely closed preventing the water from circulating. Now I don't have to freeze at night!

 

[Stadan20]

That's pretty funny

 

[shambolic]

FFS I despair