MARS 11945 Start Capacitor

The MARS 11945 Start Capacitor is a high-performance motor start capacitor engineered for intermittent duty in residential and commercial HVACR systems. Rated for 88-108 MFD (microfarads) at 220/250VAC, this round electrolytic component provides the high starting torque necessary to overcome the inertia of heavy compressor and fan motor loads. Designed with a moisture-resistant phenolic resin case, the MARS 11945 is built to withstand the rigors of mechanical vibration and high-temperature environments typical of condensing units.

For service technicians, this 88-108 uF 250V capacitor features standard 1/4 inch dual blade terminals for rapid field replacement. It is essential for single-phase induction motors that require an artificial phase shift to initiate rotation. When a motor hums but fails to turn over, replacing the existing HVAC start capacitor with a correctly matched MARS 11945 ensures the compressor reaches operating speed quickly, reducing inrush current and preventing unnecessary stress on the windings.

• High Torque Delivery: Provides the essential electrical boost to start PSC and single-phase compressor motors efficiently.
• Durable Construction: Housed in a non-polarized, moisture-resistant phenolic case for reliable performance in harsh HVAC environments.
• Universal Compatibility: Industry-standard 88-108 MFD range makes it a versatile replacement for many OEM motor start components.
• Compact Round Form Factor: Designed to fit standard motor mounting straps and capacitor covers.

Can I use a higher voltage capacitor as a replacement?
Yes, you can use a capacitor with a higher voltage rating (e.g., 330V) to replace a 250V unit, provided the capacitance (MFD) remains within the 88-108 range. You should never use a lower voltage rating than the original specification.

What are the signs that my start capacitor has failed?
Common indicators include the motor "hard starting," a loud humming noise without the motor turning, or visible physical defects such as bulging or leaking fluid from the phenolic case.

Does this capacitor replace the run capacitor?
No. The MARS 11945 is an intermittent-duty start capacitor. It must be used in conjunction with a potential relay or centrifugal switch to drop out of the circuit once the motor reaches approximately 75% of its rated speed.

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.