Do Combined Feeds And Vents Also Suffer Blockages?

[plumbandplumber]

Just a general question. It seems to be well known that for certain reasons, cold feeds on o/v systems collect magnetic debris. Do combined F and Vs get the same problem?

 

[albatross]

Yes the do but they are minimum 22mm not 15 so dont block so often. You can only have them if the boiler has an overheat stat though.

 

[0304Driver]

They do block, but as albatross says not as often, I had one they other day where the open vent/feed was blocked solid for over two meters! No wonder the system had loads of air in it!