[fransje26]

From [1], it looks like the 737 flight deck ventilation bypasses the mix manifold.

This does not seem to be the case for the A320 family of jets. [2]

[1] https://www.youtube.com/watch?v=AAy_ch6sfOQ&t=1707s

[2] https://youtu.be/4Yf-0_UTbRs?feature=shared&t=311

https://youtu.be/4Yf-0_UTbRs?feature=shared&t=311