I was tired of choosing between fresh air and high heating bills, so I built a recuperator from simple, easy-to-find materials. The full step-by-step build and cold-weather tests are shown in the video embedded below. You’ll see exactly which materials worked, where I went wrong, and how simple 3D-printed parts and sealant fixed things.
Youtube video is Here: https://www.youtube.com/watch?v=ZZr0pUTTL6c