Ice Cold Rad, Freeeeezzzzziiiiinnnnggggggg

[cocnee]

I have a Worcester 28 and all the rads are warm apart from the bedroom one.

The pipes are hot too touch but the rad is stone cold, like the cup of tea I forgot this morning.

Their is no trapped air anywhere, the boiler pressure is 2 and we recently had 2 heat exchangers replaced.

How would I make the rad hot again.

I bled it and clearish water came out the top.

Rad info......

Thermostat one end and the feeder at the other end.
Bleeder unscrews at the top.

Tahnking all you tradesmen in advance

 

[scatmanjohn]

Check that the trv pin is not stuck down.

 

[bengasman]

...we recently had 2 heat exchangers replaced...

Pretty good chance you have a lot of gunk in the system blocking the flow. If my guess is correct, get ready for hex number 3. and 4 and 5

 

[cocnee]

Thanks for you responses.

1. What is a TRV pin and where would I find it...

Bleeding the rad is not a problem as its filled to the top with water.

2. What do you mean by get ready for hex number 3. and 4 and 5. (I'm scared.

***** update......

The pipe with the thermostat is warm, but the feeder pipe is cold and the rad is full of water.

The other rads are still boiling.

 

[xr4x4]

you unscrew the trv, the pin is underneth.

try turning off one or two other rads, see what that does.

 

[bengasman]

2. What do you mean by get ready for hex number 3. and 4 and 5. (I'm scared.

As it is extremely unlikely that the main hex goes bust twice, I assume it was the plate hex. If the plate hex causes a problem twice, it is likely to be gunk from the system that is filtered out by the plate hex. If that were the case, the gunk is shifting and it will happen again and again until the system is clean.
The solution is to clean the system. Very common problem.

 

[someonelse]

Are you sure the feeder pipe at the opposite end to the thermostat is open? Partialy or fully? Take the cap off (cometimes there's a screw to undo to release it) and use pliers/spanner to turn the 'tap' underneath.
Anti-clockwise to open!

And check the thermastat end too. Remove the stat (don't worry, water doesn't leak!) and check the pin that open/closes the valve is working freely.

With both ends are open try increasing pressure by turning off other rads.

If all that fails, you've got a gunked-up rad. Plumber in to flush the system or change the rad.