Lennox 57M66 Pressure Switch 318820-201 specifically where a Teflon PTFE

specifically where a Teflon PTFE seal is required to handle refrigerant flow or pressurized gas without degrading

Its lightweight design allows for direct mounting via a 1/4 inch female flare SAE connection with an integrated deflator

failure to close the pressure switch during the pre-purge cycle

Space-Efficient Design: The 90-degree angle allows for precise gauge orientation in condensed piping layouts

making it essential to verify your specific chiller model and serial number before ordering

Lennox 57M66 Pressure Switch 318820-201 specifically where a Teflon PTFEThe 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