Turns out this was a blocked condensate pipe not air trapped in the boiler - though they sound identicalGot some air in the central heating pipes and it's doing my head in
Got back from a week away (so hot water/heating not been used) yesterday and the boiler wouldn't start - gave the warning for pressure issue (cause by air in pipes)
Couldn't find a radiator key so went out this morning, bled all the radiators - hot water back on fine, tried the central heating and it's bubbled some more air around the system
Now I've just spent the whole day resetting the boiler, turning on the central heating, leggings upstairs to bleed the radiators in the hope I catch this bubble, failing, boiler turning off, leaving it for a bit - wash rinse repeat
I'll get it eventually but it's so frustrating, wish the boiler wasn't too clever for its own good and just let me live with the bubbley pipes
Unplugged the condensate pipe from under the sink and bunch of rank water flooded out (all over me, sat under the sink thinking it would just be empty) - cleared out the connector and it works fine
Was so close to calling out a plumber for the trapped air, as well
