It connects the burner air pressure to the top of the regulator diaphragm in a negative pressure system

By transitioning to a thermopile-based ignition system

ensure those components are on hand

The Safgard Model 1100 LWCO must be purchased separately if you are performing a new installation

optimizing furnace efficiency and ensuring the pressure switch closes reliably for consistent ignition cycles

York S1-6806-3351 Limit Switch 319847-401 It connects the burner airThe York S1 6806 3351 Limit Switch is a critical safety component designed for high performance thermal regulation in York HVAC systems. Engineered for precision, this bimetal limit control features a factory calibrated setpoint to protect the heat exchanger from overheating conditions. With a switch opening temperature of 150F and a closing temperature of 115F (Cl115 Op150), it ensures the burner circuit is interrupted if internal temperatures exceed