3W2 – HARD START KIT (3 WIRE, 3.5-5 TON)

If your compressor hesitates or trips the breaker on hot days, a hard start kit helps. The Supco 3W2 is a 3-wire kit with relay and start cap for larger 3.5-5 ton compressors in bigger homes and light commercial systems.

Specs: 3-wire, 3.5-5 ton, potential relay + start cap, Supco CSRU2

Replaces: 3W2, CSRU2

Fits: Single-phase compressors in 3.5-5 ton AC and heat pump systems. All major brands.

Need help? See our AC Not Cooling Troubleshooting Guide or Capacitor Cross-Reference Chart.

In stock at Open To Public HVAC Parts in Dallas. We test parts at the counter before you buy. Call or text (214) 340-9421.

Cross-reference numbers

This part replaces the following OEM and aftermarket numbers:

• 3W2
• CSR-U2
• HARD-START-KIT
• SUPCO3W2
• SUPCOSPP8E
• X4484

Not sure if your number matches? Call (214) 340-9421 or bring the old part in — bench-testing is free.

Fits these models

• SUPCO3W2HARDSTARTKIT3-WIREFOR35-5TON
• SUPCOSPP8EALTERNATIVEFORDIFFERENTTONRATINGS