MARS 12894 Run Capacitor

The MARS 12894 is a professional-grade 55/7.5 MFD 370V round dual run capacitor engineered for demanding HVACR applications. This dual-rated component provides the specific capacitance required to support both the compressor and the condenser fan motor within a single residential or light commercial AC unit. Built as a direct MARS Blue Series replacement, it features high-grade metallized polypropylene film technology for thermal stability and low power loss. The 370 VAC rating ensures reliable dielectric strength during continuous operation, effectively handling the voltage spikes common in outdoor condensing units. Its physical round metal canister design allows for standard mounting in existing strap brackets. For technicians, the clearly marked terminals facilitate fast wiring, ensuring you maintain the correct microfarad tolerance levels necessary to protect motor windings from overheating or premature failure during high-amperage startups.

Key Technical Benefits

• Dual-Rated Output: Provides 55 MFD for the compressor and 7.5 MFD for the fan motor in one compact HVAC dual capacitor.
• Pressure-Sensitive Interrupter: Integrated internal safety mechanism designed to disconnect the capacitor in the event of an internal fault or end-of-life pressure buildup.
• Broad Compatibility: Serves as a heavy-duty 370 volt run capacitor replacement for various OEM brands requiring these specific microfarad ratings.
• Environmental Resilience: Rated for operation in ambient temperatures up to 70°C, preventing capacitance drift in extreme heat.

Common Installation Questions

Can I use a 440V capacitor to replace this 370V MARS 12894?
Yes, a capacitor with a higher voltage rating can safely replace one with a lower rating, provided the MFD (microfarad) values match exactly. The higher voltage rating provides additional dielectric headroom.

Which terminals represent the fan and the compressor?
Standard wiring identifies 'HERM' for the compressor lead, 'FAN' for the condenser fan motor, and 'C' for the common line. Always verify your wiring harness against the 55/7.5 MFD dual run capacitor markings before powering the system.

What are the symptoms of a failing 55/7.5 370V capacitor?
Common indicators include a humming compressor that fails to start, a condenser fan spinning slowly or not at all, and visible bulging or leaking at the top of the metal canister.

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.