Do I need an Air Separator?

[Wernlas]

I have a Myson Aerjec 2 Air Seperator in my system, or at least I had one, I've just had to cut it out as i'm having to move some pipes in the airing cupboard.

Do I need one?
Can I not just remove it for good?

 

[namsag]

No its perfectly ok not to use one in fact they have a habit of blocking up.
just remember and have open vent cold feed within 6 inches of each other

 

[Wernlas]

Thanks namsag, would it have been put in for a reason though?

I've read about the 15cm rule between Cold Feed & Vent connections.
What is this for?

I'm updating my whole system as it previously just had TRV's on all the radiators and a Tap Stat on the cylinder. I'm converting it to a Y-Plan with TRV's, Room Stat & Tank Stat.