One radiator is cold

Killbi11 · Posted: Fri Nov 23, 2007 11:43 am Post Subject: One radiator is cold

Hi,

I live in a tenement flat and have a system of 5 radiators throughout the flat. 4 of the radiators are very hot but one of the radiators is cold.

I have bled all radiators and still the problem persists. I don\\\'t know if this matters, but the radiator that is cold is furthest away from the boiler.

Any suggestions?

Edit:-

1) Boiler make / model (gas or oil) - Gas - Celsia F1

2) What is / is not happening - one radiator is not working

3) Has ANYTHING else been done or changed recently - nothing changed at all

4) When did the problem start? - about a week ago

5) When does it happen? eg, heating coming on or going off. - when the heating is turned on.

hi-spec plumbing heating · Posted: Fri Nov 23, 2007 11:48 am Post Subject:

close all the other rads, then when faulty rad gets hot open others

Killbi11 · Posted: Fri Nov 23, 2007 11:53 am Post Subject:

Hi,

Thanks for the quick reply!

I will go and try that now and see what happens.

KB

Killbi11 · Posted: Fri Nov 23, 2007 1:24 pm Post Subject:

Well, closed all other radiators apart from the cold one and, after an hour, it is still cold....

Any other suggestions?

If it's any help, the pipe leading into the radiator is cold.

hi-spec plumbing heating · Posted: Fri Nov 23, 2007 1:26 pm Post Subject:

does it have a trv fitted on one end

Prof.plumb · Posted: Fri Nov 23, 2007 1:35 pm Post Subject:

TRV is a thermostatic radiator valve.

Killbi11 · Posted: Fri Nov 23, 2007 1:46 pm Post Subject:

Sorry, I'm pretty clueless when it come to these things.

It looks like it has a TRV at one end (the knob makes it go hot and cold and notches run from 0 to 6) but not sure if there's a difference between a TRV and a valve. This is what I used to shut off the radiators (I turned them to zero).

hi-spec plumbing heating · Posted: Fri Nov 23, 2007 1:48 pm Post Subject:

has the cold rad got one on and is it set to the highest setting

Killbi11 · Posted: Fri Nov 23, 2007 1:55 pm Post Subject:

Yeah it does, and it's set to the highest setting.

By the way, thanks for the help on this.

Prof.plumb · Posted: Fri Nov 23, 2007 1:55 pm Post Subject:

Ok well that bulbous thing that you turn the rad off with is a trv. Now what happens is they can shut off and then not re- open. There is a pin inside that operates up an down, opening and closing the valve. What you will find is that if you take the head off the valve the pin will be down and thus the valve turned off. So to rectify this push on the pin with pliers or a hammer, give it a few gentle taps and the it will pop back up and the rad will then work.

Killbi11 · Posted: Fri Nov 23, 2007 2:30 pm Post Subject:

Yes, it works when I take the head off the valve.

However, when I put the head back on it turns cold again (the TRV is turned full open at number 6). Maybe a fault with the TRV?

hi-spec plumbing heating · Posted: Fri Nov 23, 2007 2:31 pm Post Subject:

they don't last forever

Killbi11 · Posted: Fri Nov 23, 2007 3:39 pm Post Subject:

Thanks again for the help. I'll have to invest in a new TRV.

ChrisR · Posted: Fri Nov 23, 2007 4:43 pm Post Subject:

POst a pic if it has no make on it. If we can recognise it and you can get one the same and swap the head, you won't need a nasty expensive plumber, or get wet yourself

dudleypipe · Posted: Sun Dec 02, 2007 2:57 pm Post Subject:

Hi

I've had a similar problem, thank god I found this site! It turned out to be TRV head which was broken. The head on there at the minute is made by Myson - do I have to replace the head with another Myson, or will others work - any plumbers recommend some good value ones available online?

Thanks in anticipation!

Mark