Johnson Controls A99BB-25 Silicon Temperature Sensor PVC Cable 9.75" -40°F To 212°F

The Johnson Controls A99BB-25 Silicon Sensor is a small temperature-sensing device for HVAC systems. This sensor comes equipped with a small probe made of stainless steel suitable for confined spaces. It is cylindrical with specific dimensions of diameter 0.25" and thickness 2.0" so that it is easily placed in the air ducts or any other part of the heating, ventilating, or air conditioning system. It contains a silicon thermistor, a resistor whose electrical resistance changes with temperature. It is designed to be mounted on the surface, and it has a shorter cable with wires stripped at the end for connection to HVAC control equipment. Depending on the temperature in the surrounding environment the sensor sends the electrical signal through the PVC insulated cable.