Series HAV automatic vent valves are used in commercial, residential and industrial hydronic heating applications to provide automatic or manual air venting in baseboards, convectors, radiators and high points in piping systems. It consists of a 2-piece, chromed brass body construction, stainless steel check valve, brass disc bearing cover, copper thermostat assembly, neoprene O-ring, cellulose fiber disc, replaceable cartridge and ABS heat-resistant handwheel. Cartridge can be easily maintained/replaced without system shutdown. Series HAV is ideal for use with hot water and low pressure steam systems.