Navien Dual Venturi. The navien cascading system also balances out the workload of each unit for longer life. All navien boilers ship with an automatic air vent, which is typically mounted at the top of the boiler.
This navien 30013983a dual venturi motor is a genuine oem repair part. All navien venturi parts are brand new in the original. This navien 30013983a dual venturi motor is a genuine oem repair part.