Run Capacitor, Round, 12.5 MFD, 440/370

HVAC-Grade Performance – Mars 12733 12.5 MFD Round Motor Run Capacitor, 440/370V

The Mars 12733 Motor Run Capacitor is designed to support permanent split capacitor (PSC) motors in HVAC applications where consistent, long-term operation is critical. With a 12.5 microfarad capacitance and dual voltage rating of 440/370 VAC, this component ensures stable power delivery to fan motors, blower assemblies, and other continuous-duty HVAC loads.

This round capacitor is oil-filled and hermetically sealed in a non-corrosive aluminum case with integrated pressure-sensitive interrupter. Mars capacitors are built to UL-810 standards and offer the durability and electrical precision necessary for high-cycle commercial and residential environments.

Professional Performance Attributes

• ✅ Capacitance: 12.5 µF ±6% tolerance
• ✅ Voltage: 440/370 VAC dual-rated
• ✅ Construction: Round aluminum canister, oil-filled, non-PCB dielectric
• ✅ Safety: UL-recognized pressure interrupter for thermal overload protection
• ✅ Mounting: Universal clamp-mount ready; fits standard round capacitor brackets

Specifications

• Frequency: 50/60 Hz
• Operating Temp: -40°C to +70°C (-40°F to +158°F)
• Dimensions: Approx. 2.5" height × 1.75" diameter
• Terminal Configuration: 2 terminals per pole (4 total)
• Agency Compliance: UL 810 Recognized

Installation Guidelines

Installation of the Mars 12733 should be conducted with the power supply disconnected and verified via multimeter. This capacitor is drop-in compatible with many OEM and aftermarket motor assemblies that require a 12.5 µF capacitor at 440 or 370 VAC. Use appropriate mounting hardware and torque terminal connections to manufacturer-specified levels.

Capacitor failure due to misapplication is a leading cause of repeat service calls—always verify motor specs and capacitor ratings prior to replacement. Ensure proper polarity and connection alignment with existing start/run circuit diagrams.

Contractor-Focused Application

For Service Technicians:

This capacitor is a standard-fit component for a variety of condenser fan and blower motors. The Mars 12733 provides consistent capacitance under continuous load, minimizing electrical phase imbalance and supporting proper torque and RPM across a wide ambient temperature range. Stocking this model ensures readiness for a wide range of field repairs.

Common Applications Include:

• Outdoor condensing units (fan motors)
• Air handler blower motors
• Ventilation and air curtain fans

Key Features Recap

• ✅ Universal HVAC Motor Support – Compatible with any 12.5 µF PSC circuit rated for 370V or 440V
• ✅ Long Service Life – Oil-filled dielectric improves heat dissipation and voltage stability
• ✅ Thermal Interrupter – Built-in safety feature shuts down under overpressure conditions
• ✅ Aluminum Canister – Corrosion-resistant, field-serviceable enclosure

Summary

The Mars 12733 12.5 MFD 440/370V Motor Run Capacitor provides field-proven performance in PSC motor applications. With robust thermal protection, industry-compliant construction, and dual voltage compatibility, this capacitor is a trusted component in the HVAC technician’s standard repair inventory. Engineered for long-term system stability in demanding temperature and load conditions.