YORK YVAA Variable-Speed Drive Air-Cooled Screw Chiller
Air-cooled VSD screw chiller rated to 21.3 IPLV EER across 150–500 TR, with a liquid-cooled drive and patented stepped VI technology for leading part-load efficiency in extreme ambient conditions.
The YORK YVAA is YORK's premium air-cooled screw chiller, covering 150 to 500 TR (524–1,750 kW) with a class-leading IPLV of up to 21.3 EER. The machine centres on a patented liquid-cooled variable-speed drive — where most air-cooled VSD chillers use air-cooled drives that add heat to the machine in already-hot ambient conditions, the YVAA's liquid-cooled drive maintains inverter efficiency and reliability even at extreme summer temperatures.
Patented stepped VI (volume ratio) technology automatically optimises compressor internal volume ratio to match operating conditions, avoiding the efficiency losses that occur when a fixed-VI compressor operates at off-design lift. The result is sustained efficiency performance across the full range of ambient temperatures and partial loads typical of a year-round installation. The ambient operating window runs from -10°F to 131°F, and Johnson Controls documents continuous operation in environments up to 52°C — directly relevant to UAE, Saudi Arabian and Qatari airport sites where summer peak ambients commonly exceed 45°C.
Series-flow evaporators and microchannel condenser coils contribute to part-load efficiency; EC fans and the VSD together deliver 15–25% annual energy savings over fixed-speed air-cooled screw alternatives. A Quick Start function allows compressor restart in 34 seconds after power loss. Available refrigerants include R-134a, R-513A and R-1234ze. The YVAA is AHRI-certified and used in the GCC market through the Johnson Controls Arabia network.
Technical specifications.
| Cooling Capacity Range | 150–500 TR |
| Cooling Capacity Range (kW) | 524–1,750 kW |
| IPLV Efficiency (peak) | Up to 21.3 EER |
| Annual Energy Saving vs Fixed-Speed | 15–25% |
| Ambient Operating Range | -10°F to 131°F / up to 52°C continuous |
| Refrigerant Options | R-134a / R-513A / R-1234ze |
| Drive Type | Patented liquid-cooled variable-speed drive |
| Compressor Optimisation | Patented stepped VI (volume ratio) technology |
| Certifications | AHRI 550/590 certified |
| Power Restoration Restart Time | 34 seconds |
Use cases.
- ›Airport terminal buildings requiring large air-cooled chiller plant operable through GCC summer peaks above 45°C
- ›Landside hotels and mixed-use developments in the 150–500 TR bracket without cooling-tower water infrastructure
- ›Airport cargo facilities and cold-chain logistics centres requiring reliable year-round air-cooled cooling
- ›GCC commercial buildings where water-cooled infrastructure is cost-prohibitive but high efficiency is required
- ›Replacement of fixed-speed air-cooled screw plant where 15–25% annual energy reduction justifies capital outlay
- ›Remote terminal buildings and satellite concourses too small for district cooling connection