Two naval engineers founded Sealed Unit Parts Co., Inc., known as Supco, in 1945 in the Bronx, New York. The company began as a refrigeration service business and developed a patented Bullet valve that let technicians repair sealed compressor units without invasive disassembly. Supco is now headquartered in Allenwood, New Jersey, with additional facilities in Wall Township built up through decades of growth and acquisition.
Product Lines
Supco manufactures replacement parts and test instruments for HVACR and appliance repair. Capacitors and hard start kits, including the SPP series that pairs an electronic potential relay with a start capacitor, address compressor starting issues across a range of horsepower ratings. Test instruments cover megohmmeters for checking compressor winding insulation and electronic vacuum gauges for evacuation work. Motors, relays, and other refrigeration and appliance components round out the catalog, expanded over the years through acquisitions including Climate Technology Corporation, A-1 Components, and Cam-Stat.
Why Contractors Specify Supco
Field technicians carrying Supco capacitors and hard start kits get parts engineered to cross-reference against original equipment components on a wide range of compressor brands. The company's test instruments, developed from decades in refrigeration service work, give installers diagnostic tools built around the specific failure points common in sealed systems. Supco's history as a service company first means its parts catalog grew out of solving real repair problems rather than starting from a parts list alone.
How to Choose Supco Products
Capacitor selection depends on matching microfarad rating and voltage to the compressor or motor being serviced, since an incorrect rating can shorten motor life or fail to provide adequate starting torque. Hard start kits are sized by horsepower range, so checking the compressor's rated horsepower against the kit's listed range avoids a mismatch. For diagnostics, a megohmmeter suits insulation resistance testing on compressor windings, while an electronic vacuum gauge supports accurate evacuation readings during system installation or repair.
Frequently Asked Questions
What does a hard start kit do for a compressor?
A hard start kit, such as Supco's SPP series, adds a temporary boost of starting torque to help a compressor overcome high startup load, which is common on older or harder-running refrigeration and air conditioning systems.
How is the correct capacitor selected for a compressor?
Capacitor selection matches the microfarad rating and voltage to the compressor or motor's nameplate specifications, since an undersized or oversized capacitor can affect starting performance and motor longevity.
What does a megohmmeter check on a compressor?
A megohmmeter measures insulation resistance on compressor windings, helping a technician identify winding insulation breakdown before it causes an electrical failure.
Are Supco parts compatible with other compressor brands?
Supco designs many of its capacitors, hard start kits, and relays to cross-reference against original equipment parts across multiple compressor manufacturers, which helps technicians stock fewer part numbers.
What is the origin of Supco's Bullet valve?
The Bullet valve was developed by Supco's founders as a way to access and repair sealed refrigeration compressor units without replacing the entire sealed system, a technique that shaped the company's early product line.