Window HRV

thingiverse

Remixed this HRV to make window mountable. I use AC infinity MULTIFAN S2 120mm blower fans and they move more than enough air to cut co2 levels dramatically in the local room of a house. I am pretty sure without making the core significantly larger to reduce flow restriction, you will need blower style fans to move enough air to matter. An NF-A12x25 is NOT enough fan. The AC infiinity Multifan S2 is 5V, has 3 speeds and even on max is quiet enough and has enough static pressure to be effective. I have been using an esp32 board with multiple SCD-40 sensors to track temp, humidity and co2 levels on both sides of the HRV and it is warming/cooling the incoming air quite effectively but I have no idea how efficient it really is. This was half fun side project, half for dealing with co2 issues caused by keeping windows closed during wild fire related air quality issues. I printed the core with Protopasta copper pla, the rest with regular PLA. You will also need this https://www.thingiverse.com/thing:1081095