Bulldog rad valve problem

[Littlejo222]

Advice would be appreciated please..
System is 1year old.. Went away for February leaving CH 'ticking over' on 12C.. On return set CH on 20C but 2 of the Bulldog valves will only let water in to the rads when fully open...They were both set on 4 while we were away..As soon as I turn the valves back from 5 to 4 now, the flow stops immediately..(in cold room) Thank you in advance for any
advice..

 

[Terrywookfit]

What is the actual room temperature ?

Try swapping the heads from a radiator that appears to be working correctly.

 

[Littlejo222]

Room temp yesterday was only 13C.. Do the heads simply unscrew? Thank you for reply..

 

[Terrywookfit]

Yes the knurled ring unscrews.

 

[Littlejo222]

....thank you..

 

[dang32]

i have had faulty heads on the bulldogs before now