DIY ventilation heat exchanger

[AC_Hacker]

Originally Posted by ham789

You want the ports exposed to the outside to be
on the same end of the exchanger. If the air doesn't
flow in opposite directions, you're giving up the efficiency
improvement due to dual cores.

If this was a single cross flow core, it wouldn't make any difference.

But with multiple cores, you are correct.

Best,

-AC