Problem Radiator

[Chris_J]

Hi all,

I have a troublesome radiator in my spare room. I normally have the valve turned right down (but cracked open a quarter-turn to allow minimal flow) since I rarely use the room. I decided to turn it up to full as we had visitors staying, but unfortunately it would only get warm at the top 4 inches of the rad.

The rad had always worked fine previously and would get red hot when I balanced the system about a year ago. There is definitely no sludge in the system as it has been previously flushed and always drains quite clean.

I've tried closing down all of the other radiators in the house and switching the pump speed at the boiler to max to try and force out any airlocks. I've also cycled the valve on/off several times and bled the whole system, to no avail.

Does anybody have any ideas as to what the problem may be?

 

[twgas]

Try opening the lockshield a little

 

[theheatinghelper]

hey mate ...im sure you may think there is no sludge in the rad but ..... if u know how .....pop it off the wall, connect a hose to one end and push water through it whilst tapping the middle and all around the cold areawith a rubber hammeror something that wont damage the rad, if then no cr@p comes out then i`d say its not sludged, but imagine you`ve had it turned off for say.... 6 months ..water is still in it but stagnent as there is no flow through it .......even if there is a tad of flow the water stagnates and ......builds and builds .....hey presto blocked rad !!!
if this still dont work ...maybe invest in a new rad!
hope this helps !

 

[Chris_J]

Thank-you for the advice. I will try opening the lockshield a little more.

If that doesn't work I want to fit some TRVs in the near future, so I'll try giving the rad a flush when I do that.