PERFECT COMPATIBILITY
The Long Term ZRUB Hard Start Kit is designed for 3.5, 4, and 5 ton air conditioning units. This kit includes one ZRUB hard start capacitor, one cable tie, and two mounting screws. UL certified and compatible with CSR-U2 hard start capacitor kits, it is engineered to fit most major AC brands with precise compatibility.
EASY INSTALLATION (5-2-1 METHOD)
The industry-approved 5-2-1 wiring method is recognized by leading compressor manufacturers for its safety and simplicity. Installation requires connecting only three color-coded wires:
Black wire → Common (C)
Striped wire → Start (S)
Red wire → Run (R)
Remember: 5-2-1 = Common, Start, Run.
SOLVES HARD START ISSUES
The ZRUB compressor saver helps reduce compressor startup time by approximately 30–50%. The CSR-U2 starting capacitor uses a high-performance multilayer capacitor and intelligent switching technology to deliver the extra torque needed for faster, smoother, and more reliable starts while reducing power strain.
UPGRADED PROFESSIONAL QUALITY
Built to meet or exceed OEM specifications, this hard start kit is manufactured using durable, high-quality materials and rigorously tested for reliability. Designed for professional HVAC service technicians.
Note: Expansion of the compressor economizer during operation is normal and caused by heat and internal gas buildup—not an explosion.
INCREASED STARTING POWER & EFFICIENCY
This hard start kit delivers higher starting torque, improves overall system efficiency, and helps extend the service life of compressors and related electrical components in air conditioning and refrigeration systems.