Air sounds only in HW side of CH, Y Type system

[Tricky Dicky]

I have noticed that I have air circulating around my hot water side of my Y type central heating system, the CH part of the system runs well and very quietly.

Any suggestions?

 

[ChrisR]

There's often an air bleed point near the HW cylinder - checked that?

 

[Tricky Dicky]

Yes, there is a old type automatic air release vale that I am thinking of upgrading it to a new fully automatic type.

 

[ChrisR]

Ah - an automatic leak valve? They're a pain and you shouldn't need to keep venting there. Shut it and use it as though it was a manual one. Just undo something to let the air out there.