Lennox 57M66 Pressure Switch R-407A This is a direct spark

This is a direct spark ignitor (DSI)

Constructed from durable brass to withstand HVAC system pressure and vibration

Fail-Safe Security: Reliable spring-return action ensures dampers move to a safe position during power loss

this valve is fully compatible with VA-7000 and VA-4233 series electric actuators

and X-2 Models (X-203-X-206)

Lennox 57M66 Pressure Switch R-407A This is a direct sparkThe Lennox 57M66 Pressure Switch is a critical safety component designed for precise combustion air proving in high efficiency gas furnaces. Factory calibrated to actuate at 1. 41" WC, this Single Pole Single Throw (SPST) switch ensures the inducer motor is generating sufficient static pressure to vent flue gases safely before allowing the ignition sequence to proceed. As a genuine OEM replacement part, it maintains the exact specifications required