Why do I have to keep bleeding a radiator?

Hi there

I've just replaced an old radiator in the top floor bedroom in the house. I was having to bleed the old one every few days and it was quite old so I decided to buy a new double-convector style one.

Now I'm finding that I have to bleed that every few days too - it's not cold all over, just patches - and when I've bled it, its back to normal for a few days again.

Does anyone please know what I should do?

In case it's of help:

- the radiator is at the highest bedroom in the house, on a floor just before you get to the attic.
- I drained the system properly before installing it, although there was some air in it when we turned the system back on.
- I'm bleeding it with the heating on.
- It's a direct water system (mega flow), in the cellar. Surely it's not having trouble getting all the way up there? One floor below and the radiators are all lovely and warm.
- This is a much higher capacity radiator. I've gone for I'd say a 3,500 btu to an 11,000 btu.

Not sure if any of this is relevant - but just I thought I would throw it in.

Any ideas?

Thanks in advance.

Bleed with heating off.

Andy.

Is it really that simple?


*leaves room holding head in his hands*

and add a corrosion inhibitor such as Sentinel X100. It will cost you about £15.

corrosion produces gas as well as sediment.

Hi - I've tried bleeding the radiator with the heating off and also using the inhibitor, but I'm still having to bleed the radiator every 3 or 4 days as it is cold in places (mainly down one side). Could any of the other things I mentioned be causing the problem. I'm lost!

Thanks in advance.