Our Christmas Present 1999 - Insulation for the heating ducts below the new addition.
             

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CJ's 46th birthday present. Fresh air with a HRV (Heat Recovery Ventilator). Carpentry and sheetmetal by CJ.

The idea is to take outside air and bring it into the house. A heat exchanger solves the problem of cold or hot air coming in. As the stale air is vented out, it warms up (or cools down) the incoming air in an aluminum box of interconnected louvres.