Central Heating problem?

HARDM2000

Hi all if anyone is in the know about central heating id appreciate your thoughts on this, i had a bathroom fitted not so long ago and since then im sure the heating has got noisier especially when starting up in the morning. Also i keep bleeding the radiators but air keeps reappearing in them, no matter how many times i repeat the process, and its always the same three radiators not any of the others?? Any comments appreciated, the system is only ten years old!

Moneymaker

Gas is normally created by corrosion of the radiators. The water should have had a corrosion inhibitor added that will minimise this. A quick "Google" of phrases like radiator corrosion inhibitor pulls up links to pages like this:

http://www.plumbingpages.com/featurepages/Installation.cfm

crox

Is it a sealed system or does it have a header tank? Mine is sealed and the manual explicitly says do not use inhibitors as did the fitter.

Moneymaker

Yes, good point. But if it has a header tank it needs the inhibitor. Also make sure the header tank has water in it. Very occasionally the ball valve sticks and the tank ends up empty - letting air in.

crox

Mind, sealed is a relative term, mine is losing water somewhere (I believe through the overflow) and I have to keep pressurising it, I'm waiting for the warmer weather as I don't want to lose the boiler at the mo.

Nikolai

If you have to keep pressurising it then you probably have a leak or a valve that's on the way out.

HARDM2000

Thanks for the suggestions yes it does have a header tank, i will check tonight if its ball is stuck, and also yes it has inhibitor in it as there is a sticker on the main insulated tank saying inhibitor present do not drain!
Will let you know how i get on.

HARDM2000

Right the tank is full so any further ideas, when the heating comes on it sounds as if its working in cycles under load, im not sure i used to hear it doing this??

rockin_plumber

When you had the bathroom fitted was anything done to the heating system..
A towel rail fitted maybe??

It could be something simple like a packing gland on a radiator valve loose...
When the pump runs in this will be enough to let air be sucked into the system.

letsbehonest

Call back the people who fitted it and tell them there is a problem.