The Johnson Controls A99BC-1500 is an industrial-grade PTC Silicon Temperature Sensor engineered for precision monitoring in demanding HVACR environments. Featuring a 49-foot high-temperature silicon cable, this passive sensor is designed specifically for deep-reach applications where standard PVC leads fail. With a robust operating range of -40 to 248°F, it provides reliable data for defrost termination, condenser fan cycling, and space temperature monitoring in walk-in coolers or industrial freezers. The A99B Series technical architecture centers around a 1,035-ohm reference resistance at 77°F, utilizing a positive temperature coefficient that ensures a consistent 0.42% resistive change per degree. This inherent stability makes it a direct match for PENN System 450, A419, and A421 electronic controls. The stainless steel probe construction offers excellent corrosion resistance, while the splashproof design allows for versatile mounting in high-humidity or wash-down conditions without compromising signal integrity. Key Benefits for Technicians: Extended 49-Foot Lead: The silicon-insulated cable allows for long-distance runs without the need for splicing, maintaining high signal accuracy over its 49' length. Broad Compatibility: Seamlessly integrates with Johnson Controls controllers including the MR series, MS series, and System 350. High Thermal Stability: Specifically rated for high-temperature environments up to 248°F, exceeding the limits of standard A99BB models. Interchangeable Calibration: Each PTC sensor is calibrated to a standard graph, permitting field replacement without the need for extensive controller recalibration. Durable Probe: The 2-inch stainless steel sensing bulb ensures rapid thermal response and long-term protection against aggressive refrigeration atmospheres. Common Questions: Can I extend the lead wire further than the 49-foot factory length? Yes, the A99BC-1500 lead can be extended up to 800 feet using 22 AWG shielded cable, though we recommend accounting for minor resistance shifts in the controller offset settings during commissioning. How do I verify the sensor is functioning correctly in the field? Disconnect the sensor from the control and measure the resistance with an ohmmeter. At 77°F (25°C), the PTC silicon sensor should read approximately 1,035 ohms. Compare your reading to the standard A99B resistance-to-temperature chart. Can this sensor be used for liquid immersion sensing? While the stainless steel probe is splashproof, for direct liquid immersion, it should be installed using a WEL11A-601R immersion well to prevent moisture ingress over time. Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
