I have a single pipe system (think that is what it is called, HW and CH come on together) in my flat which is making noise. There are 5 radiators on the system, one of those being a towel rail. The towel rail is the only one with a bleed valve at the top. There is a strange semi knocking/air gushing noise in the bedroom just before the radiator which echos in the rad itself. This has a drain valve at the bottom. All the radiators are hot including the bedroom one but the knocking only happens when the system is first on. I have tried pushing the air back in the boiler by connecting the cold mains pressure to the hot tap (used the connections on my washing machine). I am 99% sure it is an air lock but how do I get rid of it? Boiler is a Potterton Flamingo 20-30
Thanks in advance
Cy
Thanks in advance
Cy