• New Patreon Tier and Early Access Content available. If you would like to support AVForums, we now have a new Patreon Tier which gives you access to selected news, reviews and articles before they are available to the public. Read more.

Bubbling in central heating radiators


Distinguished Member
British Gas change the board in my boiler a few months ago due to it completely breaking down.

Since then I keep getting a bubbling sound in the radiators in my lounge when the system is turned on. They have all been bled with the pump turned off so this is not the problem.

Anyone got any ideas before I call BG back up?



Prominent Member
As above if you have a contract.

Otherwise, it will be air. Changing a board is unlikely to have disturbed any of the pipework (but with BG, nothing would surprise me), so it's likely to be coincidental.

If you bleed the rads with the pump not running, then the diverter valve(s) will also be closed so any air may remain trapped. Bleed them with the pump running. If you have a sealed system (which is normal for a combi) don't forget to open the filling loop to bring the pressure back up.
Last edited:

The latest video from AVForums

SVS Prime Wireless Pro Powered Speakers - Review Coming Soon
Subscribe to our YouTube channel
Support AVForums with Patreon

Top Bottom