Hood Air Drying and Cooling: A dehumidifier loop with added cooling

Our experiments need dry air inside the hood enclosure, so the system is built around a dehumidifier on the floor under the hood. A custom shroud caps the dehumidifier's outlet and captures its whole air stream, and PVC ducting carries the dry air up into the hood, so the air runs in a loop.

Running a dehumidifier in a loop has a catch: it warms the air as it dries it, so the temperature in the hood kept climbing. To fix this we added the compressor from a second refrigerator, which cools the air back down.

I designed the shroud in Fusion 360 first, then built it and sealed it onto the unit, with a window to check the airflow and condensation without opening it.