Precision-engineered for a secure mechanical fit

ensuring it withstands the thermal cycling of residential and commercial heating equipment service

Optimized Combustion: Engineered to facilitate precise gas-air mixing

making it a staple for technicians maintaining 5-ton York air handlers and rooftop units

Watts 0590721 Air Vent 321702-401 Precision-engineered for a secure mechanicalThe Watts 0590721 FV 4M1 1 Air Vent is a high performance 1 inch automatic air vent valve designed for veteran contractors managing commercial and residential hydronic heating systems. Engineered with a rugged brass body construction, this vertical pattern vent facilitates the continuous removal of trapped air from both hot and cold water distribution lines, preventing air lock and system noise. It features a 150 PSI maximum pressure rating and a