Rinnai 224080PP Concentric Condensing Vent Pipe Extension, 39"

39" Concentric Vent Pipe Extension for Rinnai Ultra Series Condensing Tankless Water Heaters The Rinnai RCi Series Tankless Water Heaters use concentric venting with an inner pipe which is designed to withstand the varying temperatures throught the years of a condensing heater operation. The Ubbink Rolux condensing concentric vent design is part of the direct vent system, and has been tested and approved by CSA, a third party testing agency. The pipe consist of an outer plastic vent for air intake (5" diameter) and an inner polypropylene vent for the exhaust gases (3" diameter). Plastic Material for Outer Vent For Fresh Air Intake • Corrosion-proof • Dent and impact resistant • Casted elbows and adapters • Seamless extruded materials • Easier to cut than stainless steel • Non-flammable material (UL94-V0) • White semi-gloss finish (EU RAL 9016) Polypropylene ("PP", "Polypro") Material for Inner Vent for Exhaust • Lightweight • Flame Retardant (ULc S636 Gas Vent-BH Class IIC 110°C/