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Wirsbo hePEX is a crosslinked polyethylene PEX-a pipe that features an oxygen barrier for use in radiant and hydronic heating and cooling systems. Wirsbo hePEX pipe is used for closed-loop hydronic heating and cooling applications, including radiant heating and cooling, hydronic hot water heating, chilled water cooling, baseboard heating, and distribution piping for radiant, snow melt, turf conditioning, and permafrost prevention systems. The pipe features an oxygen-diffusion barrier that meets German DIN 4726 to prevent oxygen permeation. A polyethylene layer is extruded over the oxygen barrier to protect from site abuse and moisture saturation. Temperature and Pressure ratings: 200°F (93°C) at 80 psi (551 kPa) 180°F (82°C) at 100 psi (689 kPa) 73.4°F (23°C) at 160 psi (1,103 kPa) Linear expansion rate: 1.1/10°F/100 ft. (27.94 mm/5.56°C/30.48 m)