Please help, cold radiator

17 Oct 2006
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United Kingdom
Our system worked perfectly until it was serviced. We asked the man if one of radiators didnt get as warm because of age, size etc. He said that the system wasnt brilliant and if we turned the furthest radiator off (new) then the suspect radiator would get warmer. He did this and the warm radiator did work better. Hwever when we next turned on the furthest radiator, it will no longer work. The pipe to it is hot but all the radiator is cold. We see the man regulary and he works for a well known company and he said all of the sludge will have settled in the new radiator and that it needs flushing. Our problem is we are moving very soon and our buyer is very picky and now wants to come round to check everything works. Im annoyed because said radiator worked fine and I feel he should have warned us about this. Is it easy to flush one radiator or will the whole system need doing? How much would this cost. It is an old system with a new boiler and Im scared to mess with it as we had a few leaks when it was first fitted.
Thanks for any advice
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This is a rather confusing post as it is difficult to understand what has happened; It's an old system with a new boiler? it has had an extra radiator fitted? It's just been serviced?

Which of these is true? what boiler is it? how many rads do you have? can you approximate the heat output of the radiators?
Sorry, we had a new combi boiler fitted 3 years ago to the existing radiators, (bloke who fitted it said the radiators etc would withstand this) and had one small additional radiator fitted at the same time(this is the one that no longer works). Gas man who services our boiler annually says this new radiator is the furthest away from the boiler and by turning it off has meant all the sludge has built up in it, hence it not working??? He said the system needs flushing at a cost of about £400. Sorry if my terminology isnt right, DIY etc is something we end up paying someone else to do!!
We live in a 3 bed house with 6 radiators.
Thanks for replying
This doesn't sound right because if the radiator was turned off then no sludge could enter the radiator. If I were you I would get another RGI to look at your system if you get no luck with it yourself. When was it last serviced? Has it been pressurised to the right amount?
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Six radiators and a newish combi? heat should be positively roaring around the system. Try offering up a magnet to the copper tails of the radiators, if it is attracted then you do indeed have a sludged up system. Expect your hot water to fail in the near future if not corrected very quickly.
Thanks that makes sense. The small radiator was on originally but was turned off to try and make the next radiator generate more heat on the advice of the gas man. I seem to remember him saying that because it was the last radiator and because it had been turned off the sludge that had accumulated there would have sort of solidified and now wouldnt let the hot water through.
We are in the 3 star with 'well know company'. Would you call them out? The gas man from this co said it wouldnt be covered when we asked as it needed flushing and this isnt covered. Seems unfair as it worked until he said to turn the radiator off.
Thanks for replying
why do you need system flushed and why you got sludge ? if your combi was fitted three years ago the system should still be clean from the flush and clean it had before the boiler was fitted. you cant get anything in a radiator with the valves turned off. sounds like you are not getting good advice. so did this big company fit your boiler in the first place ?
has the radiator thats not working been bled with the system turned off?. sounds more like trapped air or valves not open, i can not believe a 3 year old system that sludged up
have you not tried turning all rads off except these two maybe just one to start with
Thanks for all the advice. As you may have guessed Im a typical female who is clueless when it comes to things like this.
The system is old but the boiler is 3 yrs old and the bloke who fit the boiler flushed it out.
We are in British gas 3 star and its the engineer from there that suggested turning the rad off and subsequantly said it isnt now working because of sludge.
We got a corgi registered bloke from the paper to fit the boiler as British gas was too expensive buy a massive amount.
Ive bled the radiators with the system on??? but I will try it with the system off and I will try the system with just the one rad on, then the two, never thought of that.
Thank you so much for all your advice, its really appreciated.
Eliteheat, thanks for your advice.
:oops: Whats the copper tail of the radiator please? :oops: :oops:
I'd love to get to the bottom of this if I could without it costing more money.
The tails are the bits coming off the valves, but like the others have said I doubt very much that you have a sludge/contamination problem. Try following the previous advice and see what happens.
Thanks everyone, I now have a perfectly working radiator :D
Was telling my Mums friends about this post and her hubby came round tonight and fixed it, so much for the 'expert' gas man and his flushing suggestion. I dont know what he did but he did something to the valve.
Its awful isnt it as I could have spent and wasted over £400 on the advice of someone you would trust.
Anyway, very happy and thanks very much to you all again
dizzy if i was you i would make sure that service guy from that 3 star service doesnt touch your system again . why dont you get a local corgi guy just to service your boiler once a year? if you go on corgis web site type in your post code you will find some one near you . that wasREALLY NAUGHTY telling you the system needed flushing , not the 3 star service you would expect
Yes agree not a good service. Honestly dont think this bloke was trying to rip us off, we see him regularly in the local pub, think he was trying to palm us off really.
We are the sort of people that if somethings going to go wrong, then it goes wrong for us!
We stayed in the gas care after the old 25 yr old boiler, which was better than our new one! New boiler, broke about 3 times, leaky radiators so just thought that an annual service wouldnt be much cheaper than what we are paying now and it was peace of mind.
Will get great pleasure telling gas man and his gas man friends that it didnt need flushing in the local on Friday.
Thanks for all your help.

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