An economical venting solution for condensing and noncondensing appliances, the Concentric Venting System (CVS) features a UL1738 approved super-ferritic stainless steel inner wall. The proprietary twist-lock connection eliminates use of clamps or mechanical fasteners and saves installation time. Only one penetration is needed through the roof or the wall for both exhaust and combustion air. Multiple pipe lengths and telescoping pipe extensions eliminate field cutting of pipe. CVS is the only concentric vent system to incorporate o-rings on the inner wall and outer casing to prevent exhaust or combustion air leakage. Custom adapters are available to transition from co-linear to coaxial venting systems. The built-in condensate management system prevents standing condensation. The Concentric Venting System is a fully sealed, gas tight system to deliver superior performance with the heating unit.