Carrier 50TG500097 Flue Box 318172 701 the unit includes large arch the unit includes large arch window box lugs and dual quick connect coil terminals it utilizes a voice coil actuator to provide instantaneous response to signal changes from Maxitrol Selectra Series 14 and Series 44 electronic modulation systems The Carrier 50TG500097 Flue Box is a critical combustion component designed for precise integration within Carrier rooftop units and high capacity gas fired heating systems Technicians should verify the condition of existing seals and apply high temperature RTV or new gaskets as specified by the service manual