Mars MARS-14003 Motor Run Capacitor 3 Mfd 370V Oval

Product Description

The MARS MARS-14003 is a single-section motor run capacitor rated at 3 microfarads (MFD) and 370 volts, housed in an oval aluminum case. Motor run capacitors maintain phase shift and improve running efficiency in single-phase AC motors found in HVAC condensers, air handlers, and heat pumps. This unit is rated for 60,000 hours of continuous operation across a temperature range of -40 to 70 degrees C, making it well suited for year-round residential and light commercial service. The 4-terminal, A-base configuration and compact oval form factor simplify drop-in replacement in tight equipment cabinets. Domestically produced for consistent quality control.

This capacitor is used in single-phase HVAC motor applications including condenser fan motors, blower motors, and compressor start-assist circuits requiring a low-capacitance run cap. Its 370-volt rating covers the standard operating range for residential and light commercial split systems and package units. The oval form factor and A-base mounting style fit common OEM capacitor brackets without modification. Technicians replacing failed or weak run capacitors due to bulging, leakage, or out-of-tolerance MFD readings will find this a straightforward swap at 50 or 60 Hz.

Key Features

• 3 MFD capacitance, single-section design for dedicated motor-run duty
• 370-volt rating suitable for standard residential and light commercial HVAC motors
• Oval aluminum case with A-base mounting for common OEM bracket fitment
• 4-terminal configuration supports flexible wiring layouts in the field
• 60,000-hour rated operational life for long-term reliability
• Wide temperature range of -40 to 70 degrees C for year-round performance
• Domestically produced; rated for 50/60 Hz systems

Compatibility

Designed as an OEM-style replacement run capacitor for single-phase HVAC motors operating at 370 volts and requiring 3 MFD capacitance, including condenser fan and blower motor applications in residential and light commercial systems.

Installation Notes

Motor run capacitors must be installed by a qualified HVAC technician. Disconnect and lock out all power to the unit before handling any capacitor — stored charge can remain present even after power is removed, so discharge the capacitor safely using an insulated resistor before touching terminals. Verify replacement MFD and voltage ratings match or exceed the original specification before installation. Follow NEC guidelines and local codes for low-voltage motor circuit service.

Technical Specifications

• Capacitance: 3 MFD
• Voltage Rating: 370 volts
• Type: Single Section
• Frequency: 50/60 Hz
• Temperature Range: -40 to 70 degrees C
• Terminals: 4-Terminal
• Mounting Base: A Base
• Case Height: 1.5 inches
• Overall Dimensions: 2.16 inches W x 1.31 inches D x 3 inches OAH
• Shape: Oval
• Case Material: Aluminum
• Operational Life: 60,000 hours
• Country of Origin: Domestic

Standard Information

• Brand: MARS
• Manufacturer Part Number: MARS-14003