Mercoid DA-438-4132-4N Temperature Control Switch 50-150°F

The Mercoid DA-438-4132-4N is a robust temperature control switch designed for precise monitoring and control in industrial settings. Manufactured by Mercoid, a division of Dwyer Instruments, this device utilizes a mercury switch mechanism for reliable operation within a temperature range of 50 to 150°F. It is commonly applied in HVAC systems, process heating/cooling, boiler controls, and equipment safety applications where maintaining specific temperature thresholds is essential. Key features include a capillary bulb sensor for remote sensing, adjustable setpoints, and high electrical ratings suitable for controlling loads like heaters or alarms. Advantages over similar products, such as electronic switches, include mechanical simplicity, no external power requirement, and proven durability in harsh environments with vibration or moisture. However, the mercury content necessitates careful handling and compliance with environmental regulations for disposal. Drawbacks may include slower response times compared to digital alternatives and potential obsolescence in mercury-restricted areas. Overall, this switch offers cost-effective, accurate performance with easy installation via threaded connections, making it a preferred choice for legacy systems or budget-conscious upgrades. Condition analysis from images indicates it is used, with minor wear on the housing and capillary, but appears functional with intact internals and no visible damage. Serial number T25K-S04010101 is noted on the label. For resources, refer to Dwyer Instruments' official site for DA series bulletins (e.g., https://www.dwyer-inst.com/Product/Pressure/Switches/SeriesDA-DS/Bulletin) and model decoders; exact datasheet for this variant may require direct inquiry as it's an older model.