Industrial TCDR-137 Hydraulic Cooler Temperature Switch

The TCDR-137 Hydraulic Cooler Temperature Switch is a normally open thermal switch that closes on temperature rise to energize the hydraulic cooler fan and protect hydraulic oil from overheating. Identified by model TCDR-137 with reference number 306-3, manufactured as an unbranded unit, it features a 1/2" NPT male (14 TPI) brass body, dual lead wires with 6-inch leads, and a 1000 PSI maximum pressure rating. Temperature settings are typically 140°F or 180°F depending on suffix configuration, with approximately 20°F of hysteresis, and it is designed for hydraulic oil and compatible fluids in oil coolers, reservoirs, or hydraulic piping. Widely used in hydraulic power units, concrete mixer trucks, mobile hydraulic equipment, industrial presses, and material handling equipment for automatic cooler fan activation; the unit is a discontinued OEM component available through surplus channels.