ensure the operating frequency and current stay consistently above the fixed 0

this oil burner relay is optimized for Wayne Combustion's proprietary control logic

including the plunger assembly and return spring

It is a double-pole

High-Temperature Sensitivity: Calibrated to trigger exactly at 270 degrees Fahrenheit to prevent damage to surrounding components and ensure safety

Lennox 19L57 Pressure Switch 30067439-890 ensure the operating frequency andThe Lennox 19L57 Pressure Switch is a critical OEM safety component engineered for precise airflow monitoring in residential and commercial furnaces. This . 25" WC pressure switch is designed to verify that the draft inducer motor is creating sufficient negative pressure to vent combustion gases safely before allowing the ignition sequence to proceed. As an SPST (Single Pole Single Throw) configuration, it provides a reliable normally open circuit