The rubber well cap is critical for keeping moisture and dust out of the well and ensures the remote temperature sensor stays fully seated for accurate thermal transfer

This model is specifically intended for millivolt heating systems

and 70B water feeders and low water cut-offs

14 burner orifice

Compatibility is based on the control board's resistance requirements and the specific harness connector

Ruskin FL-165A Fusible Link 321702-401 The rubber well cap isThe Ruskin FL 165A Fusible Link is a critical safety component engineered for precision thermal response in HVAC fire dampers and ventilation systems. Designed for industrial and commercial reliability, this 165 degree F fusible link acts as a physical failsafe, melting at its designated temperature to trigger the immediate closure of fire and smoke dampers. This mechanical activation effectively isolates ductwork zones, preventing the migration of