MARS 12945 Run Capacitor

The MARS 12945 Run Capacitor is a mission-critical component engineered for heavy-duty HVACR applications requiring a consistent 40 MFD 440V rating. Built with a high-grade polypropylene film dielectric and housed in a rugged oval aluminum casing, this capacitor is designed to withstand the high-temperature environments of industrial compressors and blower motors. As a standard electrical replacement, it optimizes motor starting torque and operational efficiency in single-phase systems. The non-pcb, oil-filled design ensures stable capacitance under load, meeting strict industry standards for reliability in AC and heat pump maintenance. Its compact oval form factor allows for universal mounting in dense control boxes where space is a premium. For contractors managing HVAC motor troubleshooting, this 440-volt unit provides the necessary headroom for systems that may experience voltage fluctuations, ensuring the compressor stays within operational parameters and reducing the risk of premature motor winding failure.

• Enhanced Motor Efficiency: Improves the phase shift between motor windings to maximize torque and reduce heat buildup during continuous operation.
• Industrial Grade Build: Features a durable aluminum construction and moisture-resistant sealing for longevity in outdoor condenser units.
• Universal Compatibility: The 40 microfarad rating and oval profile make it a direct drop-in for wide-ranging fractional horsepower motor applications.
• High Voltage Threshold: Rated for 440Vac, providing superior electrical stability compared to lower 370V alternatives.

Can I use a 440V capacitor to replace a 370V unit?
Yes, you can safely use this 440Vac capacitor in place of a 370V unit as long as the 40 MFD rating matches. The higher voltage rating provides increased electrical resilience.

What are the symptoms of a failing 40 MFD capacitor?
Common signs include a compressor that "hums" but fails to start, excessive motor heat, or visible bulging and leaking from the aluminum casing.

Does orientation matter for oval run capacitors?
While the 12945 can be mounted in any orientation, it is essential to secure it firmly within the mounting strap to prevent vibration damage to the terminals.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.