New efficiency opportunities for Chiller/Rooftop units and Computer Room Air-Conditioners
Danfoss has added new 8.5 TR and 11 TR (*) variable speed compressors with IDV(**) to its popular VZH range, giving commercial cooling manufacturers the market's most complete choice of variable speed scrolls with qualified drives for HVAC systems.
In particular, the new inverter scrolls are ideal for data center close control units, where they will enable precise and efficient cooling.
They're also an excellent fit for rooftop units, helping manufacturers to meet challenging new seasonal and part-load efficiency standards (IEER), like the US Department of Energy's energy conservation regulations coming into force in 2023. Likewise, for chillers, the Danfoss VZH range will enable OEMs to develop a competitive range of systems capable to exceed the demanding Ecodesign Lot 21 targets coming into force by 2021.
Luigi Zamana, Senior Marketing Director for Danfoss Commercial Compressors, says: "The extended VZH range also gives OEMs the opportunity to work with a single, proven supplier of pre-qualified variable speed compressor and drive packages, from 4 TR up to 26 TR, with scroll technology and from 60 TR to 400 TR with oil-free Turbocor technology.
Thanks to Danfoss, there are today more options for energy efficient solutions, precise cooling and superior comfort. Danfoss enables real design strategies with the various compressor technologies in our offering, keeping in mind the total system life cycle cost".
(*) @ ARI conditions, full speed (110 RPS)
(**): Intermediate Discharge Valve for improved part-load efficiency
Worldwide, energy efficiency standards are increasingly based upon seasonal efficiency measures like the Seasonal Energy Efficiency Ratio (SEER), Integrated Energy Efficiency Ratio (IEER), and Integrated Part Load Value (IPLV). These standards are designed to better reflect the actual average and yearly load profile.
Cooling manufacturers are therefore under pressure to improve part-load efficiency in order to satisfy US-DoE, Chinese IPLV and APF and EU Ecodesign regulations, and continue to sell units in major world markets.
With their ability to continuously modulate capacity, variable speed compressors are acknowledged as a key part of meeting this challenge.
However, Danfoss VZH scrolls go further. They feature Intermediate Discharge Valves (IDVs), which prevent the over-compression losses that compromise efficiency in standard scroll technology under part-load conditions. The result is a significant improvement in integrated efficiency scores. Efficiency is further improved by the VZH range with the use of the latest permanent magnet motor technology that helps reducing power consumption at all operating conditions.
Energy efficiency is particularly important in data center cooling applications. With round-the-clock cooling demand, throughout the year, each incremental reduction in power consumption has a disproportionately large impact on energy bills – giving IDVs a clear role to play in making data centers more sustainable. IDVs will indeed deliver much higher system efficiency for the same cooling capacity especially at very high evaporating temperatures (low pressure ratios), that are typical of the data center functioning.
But servers also need precise conditions to function reliably, and the variable speed technology gives an unparalleled ability to achieve a narrow, 0.3 °C temperature window, without sacrificing Power Usage Effectiveness (PUE).
This, and the VZH extended operating map and compressors' ability to work in a wide range of conditions, makes them an obvious choice for IT close control systems – as well as rooftop units in markets where seasonal efficiency is a priority.
Importantly, Danfoss is able to supply right-sized compressors and drives as a matched, pre-qualified and certified package.
This dramatically accelerates the development process, so OEMs who are racing to satisfy new environmental standards will be able to bring new, more efficient units to market faster.
Luigi Zamana continues: "Since the beginning, we have earned a strong reputation for prequalified compressors and drives packages. We know our OEM customers appreciate it when we combine this know-how, to make their development process faster, easier and more reliable, so we're pleased to offer a perfectly matched package."
Currently, VZH compressors are approved for use with R410A – one of the most popular refrigerants for HVAC and data center applications.
With a Global Warming Potential (GWP) of less than 2500, R410A is unaffected by the F-Gas phase down in the short term. Meanwhile, Danfoss's commitment to lower-GWP alternatives – including its new, 3000 m2 testing facility for flammable refrigerants – means the company has spelled out a clear road map for a safe, managed transition before phasedown commences in earnest.
Luigi Zamana adds: "At Danfoss, we're helping HVAC engineers to solve their biggest environmental challenges– seasonal energy efficiency, and F-Gas – with sustainable, cost-efficient technology and refrigerant options.
"We were the pioneer of oil-free compressors, and variable speed inverter scroll technology, so we have the experience, support and proven reliability to help manufacturers give specifiers and engineers the dependable, efficient performance they expect."