Danfoss first developed the VZH inverter scroll compressor range in response to environmental and energy challenges. Delivering superior efficiency, precision, and 4:1 continuous modulation ratio, VZH compressors are suitable for commercial air conditioning and process cooling applications where low energy consumption are required. The third generation of the VZH variable-speed scroll compressors adds innovative Intermediate Discharge Valves (IDVs) in all models, boosting the line's part-load cooling performance.
Through its VZH compressors, Danfoss offers the widest range of variable-speed scroll compressor commercially available on the market. VZH compressors are qualified for use in tandem configuration to further extend the capacity range.
VZH compressors use variable-speed technology to deliver precise cooling and humidity management, low start-up current, and high energy efficiency to address the challenges of meeting today's energy regulations. The level of precision offered by VZH performs best in demanding, energy intensive applications with load variations.
The new third-generation VZH compressor retains the strengths of previous generations with the added benefits that come with IDV technology (for 13 to 26TR compressors). IDVs reduce excessive refrigerant compression under part-load conditions while maintaining the same cooling capacity as standard air conditioning systems. They adapt the effort of the motor to the pressure conditions in the system, opening when the operating pressure ratio falls below the built-in pressure ratio and the pressure inside the scroll pocket exceeds the condensing pressure. This reduces the effort of the motor and its electrical consumption, improving the system’s seasonal energy efficiency.
The new VZH compressors are backward compatible with previous generations of Danfoss VZH scrolls, reducing complexity and minimizing any need for redesign and requalification.
The Danfoss VZH line with IDV technology offers a single solution with a wide operating map for multiple applications that would otherwise require different optimizations and compressor models, reducing complexity and simplifying inventory management.
Looking forward, the Danfoss VZH range is expected to be qualified for use with low-GWP refrigerants R-452B and R-454B in early 2020, with R-32 following soon after.