cold radiator

[robr64]

Help!
I have an upstairs rad that refuses to heat up. Every other rad is fine....
On the right side is the thermo stat I assume where I can control the temperature the pipe below it is hot. At the other end the other pipe is cold. When I attempt to bleed the rad the pipe at the other end heats up and hot water feeds into the top of the rad. As soon as I close the rad cools down.
Is the thermo stat duff?
Could the rad be blocked?
What should I do?
What does the small valve do on the left side?

Any assistance greatly appreciated

Regards Rob

 

[gas4you]

Remove the trv head only and give the pin a few gentle taps with a hammer.

 

[robr64]

Sorry bit dim here how? Where?

 

[gas4you]

The valve on the right with numbers on. The head is removeable. Take it off and tap the pin until you can press it down and it pushes up again on its own.

 

[robr64]

ok but do i need to turn off the system.
Wont water gush out?
how does it come apart?

 

[gas4you]

Removing the head only with numbers on it will not let any water out.

Have the system on so you instantly know if the tapping has worked.

 

[robr64]

okay got the plastic top off I can see in the middle a small (about an 8th of an inch) pin in the middle.
How high should this be?
Do you think its stuck?
Im going to try and free it...
I assume there is something under it preventing the water into the rad...
Am I clse or a million miles away?

 

[robr64]

ok the pin moving but i have to use the side of a small screwdriver to help it return to top... Doesnt seem to be getting warmer.
Should I try and vent the rad again?
Bringing hot water in from the other side?
Just wait?
Get a new part?? - Hope Not!