Johnson Controls ST-W24 Immersion Temperature Sensor 10K Type II Thermistor with Brass Well

The Johnson Controls ST-W24 is an immersion temperature sensor (also called an immersion thermistor sensor or pipe temperature sensor). It comes with a brass thermowell and measures liquid temperature in hydronic HVAC systems. It sends a resistance signal to building automation systems and digital controllers.

Key Features:

• 10K Type II (10K-2) thermistor sensing element
• Waterproof stainless steel probe, about 4.87 in. long, sealed with a temperature-conductive compound
• Brass thermowell for quick temperature response
• The sensor can be removed from the well without draining the system
• Mounts directly to the pipe in the supplied brass well. The pipe needs a customer-supplied 1/2 in. Thredolet fitting.
• Pigtail wire leads with pre-stripped ends
• Thermistor accuracy of about ±0.36°F (±0.2°C)

This sensor suits chilled water, hot water, boiler and similar hydronic loops. It is also used for mechanical equipment room monitoring.