5-2-1 521-CSRU2 Hard Start Kit 3.5 to 5 Ton Hvac

Product Description

The 5-2-1 Compressor Saver 521-CSRU2 is a hard-start kit designed for 3.5 to 5-ton HVAC systems. It uses a multi-layer starting capacitor combined with smart switching technology to reduce compressor in-rush current at startup, often by 50 percent or more. This reduction in starting load protects the compressor motor, run capacitor, and other electrical components from the repeated stress of hard starts. Rated for 208 to 240 volt AC systems, the 521-CSRU2 is compatible with both reciprocating and scroll compressors. Licensed HVAC technicians install this device as a preventive upgrade on new installations and retrofit service calls alike.

The 521-CSRU2 fits residential and light commercial HVAC applications where compressor startup strain is a concern. It is particularly useful in areas with low utility voltage, on aging systems where the run capacitor is already working hard, or wherever compressor longevity is a service priority. The unit works across the 3.5 to 5-ton capacity range, covering a wide segment of split-system and package-unit installations that operate on 208 to 240 volt single-phase power.

Key Features

• Reduces compressor in-rush current at startup by 50 percent or more
• Multi-layer starting capacitor with smart switching technology for cleaner starts
• Rated for 208 to 240 volt AC systems
• Compatible with both reciprocating and scroll compressors
• Suitable for new installations and retrofit service calls
• Covers 3.5 to 5-ton system capacity range

Compatibility

Designed for use with 3.5 to 5-ton HVAC systems operating on 208 to 240 volt single-phase AC power with reciprocating or scroll compressors.

Installation Notes

Installation should be performed by a licensed HVAC technician. Disconnect and lock out all power to the condensing unit before beginning work. The hard-start kit wires in parallel with the existing run capacitor at the compressor terminals; follow the wiring diagram included with the unit and observe all applicable electrical codes. Do not energize the system until all connections are secure and covers are reinstalled.

Technical Specifications

• System Capacity: 3.5 to 5 ton
• Voltage Rating: 208 to 240 volts AC
• Compatible Compressor Types: Reciprocating and scroll
• In-Rush Current Reduction: 50 percent or more

Standard Information

• Brand: 5-2-1 Compressor Saver
• Manufacturer Part Number: 521-CSRU2