What are the heat exchanger loop pipes made from?
Geothermal earth loops are made from High Density Polyethylene, (HDPE) pipe. The circuits are either 3/4″ or 1 1/4″ diameter and headers are either 1 1/4″ or 2″ diameter. The resin is PE 3408 having a cell classification, 345564 or 345434 per ASTM Standard Specification D3350, certified as being in accordance with CSA Standard B 137.1. This is the specification referred to in CSA 445 and CSA 448 and thus is mandated by Canadian Building Codes. CSA Certified geothermal pipe will always carry CSA Certification on the pipe itself. If it does not say CSA Certified for Geothermal Systems on the pipe, the pipe is not certified for use in a Geothermal System.
