Supco

About Supco

Supco, short for Sealed Unit Parts Company, is a manufacturer of controls, service tools, and diagnostic instruments for the HVAC and refrigeration industry. Founded in the mid-20th century, the brand has built a catalog that addresses the practical needs of technicians and maintenance teams working on commercial and light industrial cooling systems. The product line spans several core families: compressor starters and hard-start devices, relays, defrost thermostats, surface-mount limit controls, hot surface ignitors, drain traps, and a range of service valves and piercing tools. Additionally, Supco offers data-logging instruments and circular chart recorders for environmental monitoring. The portfolio is designed around standard HVAC practices, making components compatible across a wide range of OEM equipment without requiring proprietary interfaces.

For the technical buyer, Supco components are specified with clear electrical and mechanical ratings. For example, the SHM350 surface-mount limit control is a manual-reset, open-on-rise SPST device rated for 350°F opening temperature and available for 120V AC or 240V AC circuits. It carries CSA and UL certifications, which are relevant for installations requiring third-party safety approvals. Similarly, the IG418 universal hot surface igniter operates on 120V AC, uses a silicon carbide flat-tip element, and comes with a 15.5-inch lead length, making it a direct replacement for specific Robertshaw models. These specifications allow engineers to match components to existing system parameters without guesswork.

Supco also addresses operational and maintenance challenges. The NPW1H negative pressure drain trap, with its PVC body and universal compatibility, is designed to collect condensate in systems operating under negative pressure, preventing water damage and maintaining system efficiency. The SL5709 defrost thermostat is tailored for commercial refrigeration, specifically compatible with Larkin brand equipment, and controls defrost cycles to prevent ice buildup. On the diagnostic side, the CR4 circular chart recorder monitors temperature in Fahrenheit and sound levels, with an accuracy of ±1% for temperature and ±1.0% for sound, and includes 60 assorted charts for extended logging. The SL300TH data logger, mentioned in the brand's broader line, records temperature and humidity with configurable sampling intervals and battery life exceeding 20 months, supporting compliance verification in temperature-critical environments.

3G Electric supplies Supco products as part of its industrial equipment distribution, ensuring that plant engineers and maintenance managers can source these components alongside other HVAC and refrigeration parts. The availability of Supco items through 3G Electric covers the range from simple service tools like pocket thermometers and nitrogen purge connectors to more complex controls and recorders. This integration allows procurement specialists to consolidate orders for both routine maintenance and system upgrades, with the assurance that Supco's specifications meet the demands of commercial and light industrial applications.

Common Applications

• Commercial refrigeration maintenance — Supco SL5709 defrost thermostat for Larkin evaporator coils
• HVAC system troubleshooting — Supco IG418 universal hot surface igniter for gas furnace replacement
• Condensate management in negative pressure systems — Supco NPW1H drain trap for rooftop units
• Temperature and sound logging in cold storage — Supco CR4 circular chart recorder for compliance documentation
• Compressor protection in light industrial cooling — Supco CSS-25U hard-start device for inrush current control
• Safety limit control in heating appliances — Supco SHM350 surface-mount limit control for over-temperature shutdown