In a rental where you can't cut through the walls introduces challenges. I wonder if anyone has created a DIY window unit that incorporates a "ZEHNDER COMFOAIR 70" which is a small contained HRV unit that has c02 detection and can ramp fan speed to match co2.
you can hookup the panasonic unit to a window manifold for a portable AC and put some insulation board over that. that is the only reasonable solution I have found for the states
I've had good success adding various utility and ventilation feed throughs in rentals with sliding glass door inserts, including large ducts for various HVAC experiments.
I start with a board and cut/slot it so it fits neatly into the top and bottom tracks, then I move the latch receiver to the board, zip a few screws through the board where the holes won't be noticed.
The glass door opening becomes a bit narrower, and I can cut as many holes as I want in that little bit of wall.
If it's painted white it usually ends up looking better than most of the corporate maintenance work on the building.
$300 option from Alibaba, http://mistersustainable.blogspot.com/2021/08/another-mini-e...
$700+ options, https://old.reddit.com/r/hvacadvice/comments/wdl0mn/do_windo...
OpenERV design (writeup pending), https://x.com/open_erv