Second question for today...
About a year ago I had a plumber in to do a few jobs associated with my new (self-fitted) kitchen. One of the jobs he did was to remove a high level fan heater that was plumbed into the central heating. Ever since he removed that, the radiator in the dining room next to the kitchen has not worked. (It definately worked before this - without doubt).
I've been up in the loft and looked at what he has done, and TBH, it makes perfect sense to me.
When I open the bleed valve at the top of the radiator I get water, not air, so it's obviously full, it just doesn't get hot. All other radiators work fine.
The system is a strange mix of microbore and standard pipe work - I think some of the radiators (including this one) were retrofitted at some point.
Do I have an air lock or something? If so, how can I get rid of it?
Cheers
Dave

Thanks Scruff - I see what you are saying. How do I isolate each pipe in turn?

Got it - thanks mate.

Dunno yet - not got round to it. Been concentrating more on my en-suite.

OK, I've just had a go at this:
I closed the lockshield valve (which was fully open BTW - is that right?), opened the thermostatic valve fully and bled the radiator - water instantly came dribbling out of the bleed screw.
I then opened the lockshield valve fully and closed the thermo valve and bled again - water instantly came dribbling out of the bleed screw again.
No luck - radiator still not getting warm.
Did I do this right?
I'm trying to get the plumber back to have a look at it - but I think he has quit the trade - he gave me fair warning of this last year so it's my fault for not getting him back sooner.
Anyway, what's the next thing to try (if anything)?

Good idea Chaddy - thanks.
I'll try it now...

Well, 10 minutes later and no gurgling - I'll leave it a while longer, but knowing my luck my pressure relief valve is stuck shut and something's about to blow up!  

I'm thinking it could be that the plumber has connected the flow pipe to the return pipe and vice versa up in the loft - in which case all I need to do is swap the valves to opposite sides of the radiator - right?
I don't fancy that too much though as it means draining the system and if it's anything like my car I'll have a pig of a job getting airlocks out again. And even after that it still might not work.

Good job the lack of radiator isn't making the room too cold to use.

Ah, but it's got a thermostatic valve on one end - am I right in thinking that water will only flow one way through one of these? Apologies if not...

As for your last question - see above, I'm experimenting with that now - fingers crossed!!

Dave you said that the lockshield was  fully open on this rad.

Did the plumber balance the system when he fitted the rads?

Check all the other lockshields( the ones with the caps on) if they are all fully open this could be the problem.

It's amazing how much difference a quarter turn affects the flow to the other rads.