MARS 12871 Run Capacitor

The MARS 12871 dual run capacitor is a heavy-duty 40/5 MFD 370 VAC oval component engineered for high-demand HVAC applications. This MARS 12871 run capacitor is a reliable aftermarket HVAC capacitor designed to stabilize voltage and current flow to both the compressor (40 MFD) and the fan motor (5 MFD) in split system condensing units. Rated for 370 volts, it features a leak-proof, oil-filled design that ensures optimal heat dissipation during continuous operation. As a replacement dual run capacitor, it is a direct mechanical and electrical equivalent for GE 97F9840 and C3405L models. The aluminum case is built to withstand internal pressure build-up, protecting the system from potential failures. For technicians performing AC capacitor troubleshooting, the 12871 offers standardized 1/4-inch quick-connect terminals for rapid installation. Precise capacitance tolerances ensure this HVAC motor capacitor maintains electrical efficiency and component longevity in demanding environments.

Key Technical Benefits

• Direct Replacement Compatibility: Seamlessly replaces 97F9840 and C3405L models without wiring modifications.
• Dual Run Functionality: Manages both the compressor and condenser fan motor with a 40/5 microfarad rating.
• Durable Construction: Oval aluminum housing provides efficient thermal management and a compact footprint for tight control boxes.
• Standardized Terminals: Features industry-standard multi-spade terminals for secure and easy field connections.
• Reliable Frequency Rating: Optimized for 50/60 Hz systems, ensuring compatibility across various residential and commercial platforms.

Common Questions

Can I use a 440V capacitor to replace this 370V 12871 model?
Yes, you can substitute a higher voltage rating like 440V if the microfarad (MFD) rating remains exactly 40/5. However, you should never use a lower voltage rating than specified by the equipment manufacturer.

What are the physical dimensions of the MARS 12871?
This is an oval-style capacitor. If you are replacing a round capacitor, ensure the mounting bracket in the condenser cabinet can accommodate the oval shape or use a universal strap.

How do I identify which terminal is for the compressor?
The terminals are clearly marked: 'Herm' is for the compressor lead, 'Fan' is for the condenser fan motor, and 'C' is the common terminal.

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.