Radiator cold on one side

[Katcha]

I had a new boiler fitted 2 weeks ago but the original radiators weren't replaced. I've had the fitter back twice to repair leaks which I'm being billed for as only the boiler was guaranteed.

I've noticed the past 2 evenings that my livingroom radiator is almost cold on one side (the side at the lockshield valve). The whole bottom of the rad is piping hot. I've phoned the fitter again and he said it won't need bled for over a year and he has already balanced them and flushed them. He want's another visit which will cost me more money. Is there anything I can do myself to resolve this?

[The Builder]

Is this the only rad affected?

[daffy654]

I would try bleeding it myself as that is usually the problem in this situation. Just because the fitter says it won't need bleeding for another year doesn't make it true.We have to bleed our bathroom radiator weekly.

[Katcha]

Yes it's the only rad affected.

The bleed valve is at the end which is piping hot which I think would indicate that there's no air trapped. It's the other side of the rad which is cool.

Should I still attempt to bleed it?

Thanks for the quick replies so far.

[The Builder]

............bit of a long shot - but, when he balanced the system, he might have left that rad with the lockshield valve just about closed.........................try opening it up a half turn...........................

[Katcha]

Interesting... the valve was fully open, I checked all the other rads and they're all fully open. I'm no expert but does this indicate the system hasn't been balanced?

From what I've read in other questions if it was needing balanced it would be cold at the bottom. The rad is very hot at the bottom.

[Katcha]

Maybe this is relevant to the problem... it's the only rad which makes a 'fizzing' sound as water flows through.

[The Builder]

The only thing left that occurs to me is that the rad is blocked up .......................the rads might be several years old.......you've had a new boiler...........it sounds like he didn't balance at all..........so he might not have flushed the system either...........fitting a new boiler could have stirred up the gunk in the system................I would drain the whole system..............flush it through..........then refill with an inhibitor added to the water...............

[gucciman]

i would also suggest the radiator is likely to be sludged up rather than airlocked. i would be questioning how and if he flushed the system when the new boiler went in because if anything goes wrong with your boiler under warranty then thats the first thing the boiler maker is going to look at and if it wasn't flushed they wont honour the warranty.
how anyone can turn round and say the radiator wont need bleeding for a year is beyond me.
is the radiator at fault upstairs or downstairs?

[Katcha]

It's a small 1 bedroom flat on the same level with only 4 rads on the system. It's getting worse daily and now I only have 6 inches of proper heat at one side. One of the other radiatiors is now starting to do the same thing.

Thanks for the advice folks, I'll contact the plumber again and see what he says.

[PAUL55]

I presume that you have changed a convensional boiler for a Combi? if this is the case, that will account for the leaks appearing as the combi is a pressurised system and will find any week ponts in the old pipework. the plumber should have realised this and not have charged you again for just tightening up a couple of nuts.The cold area on the rad will be either a air lock which could work through on its own eventually, or a faulty valve. Wait for a while until the system setles and if it dousn't sort itself out, change the valve which will cost about a tenner for the part. Remember - if it is a combi boiler and you bleed the rad, make sure you top up the pressure on the boiler again afterwards, or else the boiler will not run.

[RAYMAN]

This is a long shot after the other readers comments, there is two ends
to a radiator open the thermo-valve end fully open and at the other end take off the lockshield [this is the balancing end] use a spanner too open the valve [anti clockwise] fully, bleed the radiator this I hope should get some movement of water.
If that worked turn down the thermo-valve too about number halfway then at the lockshield end reclose the valve to give you a rad-temp that is warm,then if you want it hotter turn the thermo valve too a higher number.
Best of luck