Screaching Combi boiler

I have a C&M Britony Combi boiler. I recently repressurised the system but when I use the hot water (sink, shower) I get a screaching noise coming from the boiler, getting louder until I turn it off (the water or the boiler). It sounds like nails on a blackboard which probably isn't the best description. It has also now started dripping from the bolier -- about once every 5 seconds.

I think that there could be air in the system but it sounds more serious... pump? fan? Any ideas?

Is the ch working ok?
More info will be required.
Are you able to record the noise and post it on a web site , with a link from here?

Exactly where is the drip from the boiler coming from?

The noise sounds like "kettling" (cos it's like a kettle) and the boiler will need descaling and the rest of the system cleaning. Unfortunately unless the drip is from a joint, which can be fixed, it looks like the end of the line for your boiler. If you need a replacement, ensure your system is flushed properly, and add a strainer in the return pipe before the boiler. You will need service valves on either side of the strainer, otherwise you can't clean it without draining the system. Failing to do these things cold mean you need another boiler in a few years.

And make sure you put corrosion inhibitor in the system once it's cleaned.

C/H is fine. Worked perfectly with no noises. It's why I didn't notice the problem until I turned on a hot water tap and heard it!

I am far too worried about it to turn on the boiler and record the sound! But it does sound like an old fashioned kettle whistle.

It's not an old boiler... less than two years old. I've got some bloke coming round tomorrow morning to look at it. Hopefully, he's not a cowboy. When this is fixed, I'm paying for British Gas's 3-star service.

What happened with your boiler, out of interest?