MARS 12761 Run Capacitor

The MARS 12761 is a high-performance 25/5 MFD 370V dual run capacitor engineered for demanding HVACR applications. Designed for continuous duty, this round dual run capacitor provides the necessary phase shift to optimize motor torque and efficiency in both compressor and fan motor circuits. With a 370Vac rating, it is an essential component for maintaining the power factor and reducing the amperage draw in residential and light commercial air conditioning systems. The MARS 12761 features a hermetically sealed aluminum case and is internally protected with a physical interrupter to ensure safe operation under extreme thermal conditions, typically ranging from -40°C to 70°C.

As a veteran's choice for AC capacitor replacement, this unit meets strict EIA-456-A standards and is UL and CSA listed for reliability. The MARS 12761 dimensions are compact enough for universal fitment in standard control boxes, making it a "truck-stock" staple for technicians. When performing a 25+5 uF capacitor test, ensure your multi-meter confirms both the 25 MFD compressor side and 5 MFD fan side are within the +/- 6% tolerance range to prevent premature motor winding failure. This HVAC dual run capacitor is non-PCB and designed for a 60,000-hour operational life, providing the stability required for modern high-efficiency cooling equipment.

Key Benefits:

• Dual capacitance (25/5 MFD) supports both the compressor and condenser fan from a single, space-saving round canister.
• 370Vac operational voltage provides robust dielectric strength for standard 208/230V systems.
• Internal safety interrupter protects the system by disconnecting the capacitor in the event of an internal pressure buildup.
• Wide temperature range (-40°C to +70°C) ensures consistent performance in both extreme winter and peak summer environments.
• Quick-connect terminals for efficient field installation and secure electrical paths.

Common Questions:

Can I use a 25/5 440V capacitor instead of this 370V model?
Yes, in the HVACR trade, you can always go up in voltage (e.g., using a 440V rated capacitor in a 370V application), but never down. Using a higher voltage rating provides a greater safety margin for voltage spikes.

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

What causes a round dual run capacitor like the MARS 12761 to fail?
The most common causes are excessive heat, power surges, or age-related dielectric breakdown. If you see a "bulged" or "domed" top, the internal interrupter has triggered, and the part must be replaced immediately.

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.