Supco 3W2 Hard Start

Field installations requiring a 3-wire hard start kit for 3.5 to 5 HP compressors are best served by the Supco 3W2. As a direct replacement for CSRU2, this unit integrates a mechanical potential relay and a high-capacity start capacitor (189-227 MFD) to provide the reactive power needed for high-torque startups. Designed for 208V to 277V single-phase systems, the Supco 3W2 Hard Start utilizes voltage-sensing technology to drop the start capacitor out of the circuit immediately once the motor reaches 75-80% of its synchronous speed. This prevents winding overheating while ensuring reliable operation in low-voltage scenarios or systems equipped with TXV valves. The NATE-recognized 3W2 is a true 3-wire solution, simplifying wiring by connecting directly to the compressor’s start, run, and common terminals. The inclusion of an EZ snap bracket allows for fast, secure mounting in the upright position, essential for maintaining gravity-dependent relay orientation in demanding refrigeration or air conditioning applications.

• Instant Re-start: Voltage-sensing mechanical potential relay ensures the capacitor is ready for the next cycle without the thermal delays found in PTC-style starters.
• High Torque Output: Provides a 35-amp relay contact rating and 330 VAC capacitor for effective starting of 3.5-5 HP reciprocating or scroll compressors.
• Versatile Replacement: Serving as a CSRU2 replacement, it fits a wide range of OEM applications for single-phase HVACR units.
• System Protection: Precisely removes the start winding boost to protect against motor overload and internal thermal trips.

Is the Supco 3W2 compatible with both scroll and reciprocating compressors?
Yes, the Supco 3W2 is designed for use on any single-phase air conditioning or refrigeration unit within the 3.5 to 5 HP range, including both scroll and reciprocating designs.

Does this hard start kit require any specific mounting orientation?
For proper mechanical potential relay operation, the kit must be mounted in an upright position. Side-mounting can interfere with the internal relay's gravity-assisted drop-out mechanism.

Can I use the 3W2 to solve low-voltage starting issues?
The 3-wire potential relay is engineered specifically to provide the necessary starting torque in low-voltage conditions or long line set applications where compressors struggle to overcome head pressure.

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.