Siemens Building Technology 540-660B Sensor 318172-701 This lock-up style gas regulator

This lock-up style gas regulator is built for high-demand applications

If the limit switch is open

preventing ground faults that lead to intermittent ignition lockouts or boiler flame failure

the outdoor unit failing to engage

Siemens Building Technology 540-660B Sensor 318172-701 This lock-up style gas regulatorThe Siemens 540 660B Sensor is a staple 10K Ohm NTC thermistor designed for precision environmental monitoring in commercial HVAC applications. Engineered for seamless integration with Siemens Terminal Equipment Controllers (TEC) and LONMARK compliant systems, this Type II NTC thermistor offers a reliable sensing range from 55F to 95F. As a veteran grade wall mount room temperature sensor, it features an integrated set point slide and a flush mounted