We recently (about 2 months ago) had a Keston Celsius 25 boiler
installed, and it's been great. However, it is now making some kettling
noises which it wasn't when first installed, which seem to be getting
louder as the days go by. Nothing's changed, except the weather has got
colder and so it is running more. I posted a while ago about a sort of
"chuffing" noise it was making, this noise seems to be caused by
kettling.

I thought that as the air was driven out of the new water in the CH loop
after installation, the kettling should get less rather than more.
There's no air in the system now as far as I can tell, every bleed point
just produces water. Would it be worth trying some Fernox anti kettling
stuff or is that a waste of time.
--
Tim Mitchell