MARS 12884 Run Capacitor

The MARS 12884 is a professional-grade 25/5 MFD 440V oval dual run capacitor designed for continuous-duty applications in residential and light commercial HVACR systems. Built by Motors & Armatures, Inc., this dual section motor run capacitor provides the necessary phase shift to optimize the performance of both the compressor and the condenser fan motor. Its oval metal can architecture is constructed from rolled aluminum for superior heat dissipation and environmental protection, making it a reliable drop-in replacement for aged or failed units. Rated for up to 440 VAC, it is also fully backwards compatible with 370V systems, offering versatility for service technicians carrying limited truck stock. Each unit is oil-filled and features a physical pressure-sensitive interrupter for safety, ensuring the circuit breaks if internal pressure exceeds safe limits. This HVAC replacement capacitor is UL recognized and CSA certified, engineered to withstand ambient temperatures from -40°C to +70°C, maintaining stable capacitance for 50/60 Hz cycles.

• Dual-Action Performance: Simultaneously supports the compressor (25 MFD) and fan motor (5 MFD) for efficient system startups.
• High Voltage Versatility: The 440V rating allows this unit to replace 370V capacitors, reducing the need for multiple SKUs on your service vehicle.
• Enhanced Safety: Built-in pressure-sensitive interrupter and non-PCB oil-filled design for reliable circuit protection.
• Standardized Terminals: Equipped with ¼-inch male quick-connect terminals for fast and secure wiring.
• Durable Construction: Corrosion-resistant aluminum housing maintains integrity in harsh outdoor condenser environments.

Can I use an oval capacitor to replace a round one?
Yes, provided the capacitance (MFD) and voltage (VAC) ratings match. You may need a different mounting strap or bracket to secure the oval housing properly within the control box.

Is this part compatible with my 370V system?
Absolutely. You can always "up-rate" the voltage of a capacitor. A 440V rated capacitor like the MARS 12884 will work perfectly in a system calling for a 370V part, often leading to better longevity due to the higher dielectric strength.

How do I know if the capacitor is failing?
Common indicators include a "swollen" or bulged top, an HVAC system that hums but won't start, or a fan motor that requires a manual push to begin rotating. Always verify with a multimeter set to the capacitance (µF) setting.

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.