cold radiator

wwp8

Hi,

Can anyone shed some light for an issue I have.
I have a 4 bedroom house and in total it has 13 radiators.
in the spare room that radiator is warm at the best.
In my bedroom the radiator has does not want to even try.

all other radiators are working brilliantly.
I have already taken bled it, changed a TRV, took it out and flushed it, bled it again and still nothing.

I have noticed on the TRV side the little pipe does get warm and sometimes hot, but the pipe that goes to the radiator is cold.
It feels like it is stuck

I once tried turning on the heating with the radiator removed and at best it dribbled, but I then added pressure on the expansion vessel and it came to life with water all over the place, (I had to see what happens), so that to me proves that water do flow.

I have checked the pressure on the expansion vessel and it currently shows 1.2bar, my next step in the next couple of weeks would be to swap it with a known working radiator to see if the radiator is faulty, however before I do that, does anyone have a better idea?

Thanks in advance

dunroving

[Health warning: I am no expert with radiators, but had a similar experience]

Could the valve be sticking? In my last house a guest turned the radiator valve off (and opened the windows in midwinter as she likes to sleep in the cold!). I didn't realise for a few days as the guest room door was closed. When I turned the valve way back on, the rad stayed cold and it turned out the valve was stuck, partly because she had jammed the control hard closed.

I have heard it suggested that removing the control and tapping the valve with a hammer might loosen it - but maybe turn off the heating before trying this, and use a small hammer. ;-)

ETA: Just found this Youtube video https://www.youtube.com/watch?v=phFW-IIsH54

wwp8

No, unfortunately it's not that, i have replaced the valve with a new one

Lorian

Is the lock shield valve on the other end of the radiator turned off?
Does it need bleeding?

billy2shots

Take the TRV off. There should be a pin on the radiator pipe That's 'up'. You can only see this with the trv off. If the pin is stuck down then it is stopping water getting to your rad. When the trv is set to off it pushes this pin down. When you turn up a trv it allows the pin to naturally lift up.

If it's stuck, give the pipe a little tap around it (carefully). I've see people use plyers but I wouldn't recommend that.
The pin when you push it down with your finger should pop up when let go.

ariba10

The first thing I would do is when the c/h is on turn off all the working rads and see if that makes any difference.

wwp8

I have taken the trv out a few days ago, the little thing is in the Up position because I can push it down and it easily springs back up.
The other end of the lock shield I have tried fully turned anti clockwise and also tried clockwise, and it made no difference

Lorian

have you bled any air out of it?

wwp8

ariba10 wrote: »

The first thing I would do is when the c/h is on turn off all the working rads and see if that makes any difference.

I did try that once, but I can't decide how long to wait before I mark that as a fail too. I think I had the heating on for about 20-30 minutes.

The only thing I don't know if the radiator is the last one in the chain

wwp8

Lorian wrote: »

have you bled any air out of it?

When I flushed it, and put it back on, there was air, but it's now clear water

billy2shots

Where is the thermostat? Is it getting too warm in your house before the hot water gets to the two problem rads?
Turn the thermostat right up and the water temp on your boiler and see if the heat gets to the two rads with issues (sometimes I have the rad closest to the stat off to avoid this situation).