One radiator cold

[dcr2007]

One of the radiators in my house is cold

If I bleed it and leave it bleeding into a bucket the rad gets hot BUT when I close the bleed valve it is cold again within 30 minutes

It as been like this for quite a while

All my valves have terms on

I have just had the boiler serviced but the fault was there before the service

Any ideas

Thanks

 

[Meldrew's mate]

Could be the TRV (if that's what you're calling a "term") is stuck shut. Take it's head off and see if the pin moves in and out about 3 mm under hand pressure. If not it's probably stuck down; search for the solution on here, exact method depends on make/model of TRV.

MM

 

[JohnD]

or you might have sludge. Black water when you bleed the rads is a clue.

See also
//www.diynot.com/search/forum....t=3&author=&search=Search+Forum&mode=advanced
as this is the time of year for this question.

140 in the last three months

and look at "similar topics" at the bottom of this page

I see you previously had the filling valve open on your Glow worm combi boiler so it will have washed out the inhibitor and introduced dissolved air, which speeds up corrosion.

 

[dcr2007]

Valve is a Westherm, how do I check if its stuck

 

[JohnD]

remove the thermostatic top

you will see a pin.

press it carefullly straight down (you will need a flat tool as it will be too stiff to push down with your hand

see if it springs straight out again.

to not pull it, or bend it sideways

 

[dcr2007]

How do I do this

Thanks

 

[nickso]

westherm heads have a knurled collar to remove them iirc