Bleeding air from Central Heating System

[panda_96]

Boiler is making a gurgling sound and keeps short cycling. I believe there is air in the the system and I've already bled all the radiators. This is the pipe leading into the water cylinder, is it where I should be bleeding the air from?

 

[Ben-gee]

No, that is to drain the cylinder- leave it alone!

 

[panda_96]

No, that is to drain the cylinder- leave it alone!

Okay I see, I'm trying to follow these instructions:
But struggling to understand where to drain.

 

[Ric2013]

Not seen the video, but that guy's an idiot. It may be totally wrong.

Sure the boiler isn't just kettling?

 

[panda_96]

Not seen the video, but that guy's an idiot. It may be totally wrong.

Sure the boiler isn't just kettling?

I'm not sure, the boiler will fire up and stay on for a minute or 2 then stop with the burner light flashing. Then after a few minutes it will start again, this repeats indefinitely. Throughout all this there is a gurgling sound, the problem seems to be exactly as described in the video I posted.