Kettling noise from boiler...using Fernox F2?

[markyhud]

I'm currently running some Fernox F3 round my system. Its 14 year old vented system, Ideal Classic boiler and has never had any kind of powerflush or chemical treatment. It's been noisy with air/?hydrogen for a while now so trying the chemical route. No cold spots at bottom of rads just air/gas accumlating in bathroom rad. I plan to keep the f3 in for a week as stated on the instructions but now I think the problem might be more limescale although this is an educated guess. It's noisy when CH/HW is initially called for and sounds like air is gurgling and rushing from the boiler and through the pipes. Once this initial noise subsides everything is pretty quiet but at times standing next to the boiler it makes like a "glug"/"gurgle" sound which is followed by a surging and trickling sound. I presume this is "kettling" and could this be from a scaled up heat exchanger?
The F3 seems to have made a bit of a difference even after just 24 hours. I know it says the cleaner is for scale but I was thinking of dosing it with boiler silencer F2 next week and F1 inhibitor. Am I chucking money away with the F2? From reading this seems like it is dedicated soley to remove limescale whereas the F1 prevents it. Any comments would be greatly appreciated

 

[Chalked]

Sounds like your system has a lot of air in it. No amount of chemical will cure that. It's generally down to badly installed pipework not venting naturally or incorrect placement of he cold feed and vent pie connections.

 

[markyhud]

Sounds like your system has a lot of air in it. No amount of chemical will cure that. It's generally down to badly installed pipework not venting naturally or incorrect placement of he cold feed and vent pie connections.

When the house was new ithe whole system was whisper quiet. Over the years it's gradually got noisier but I've tended to ignore it really. I think u may be right about a pipework configuration issue. Last week I bent the arm of the ball cock to lower the level of water in the f&e tank. It was about 3/4 full when cold. It's now about 1/3 full. I do plan on getting a professional out in the new year to have a gander at everything and have a filter fitted. In the interim I thought I would try the chemicals.