The new VRV IV+ range has been designed with an entirely new compressor that delivers an average 15% increase in seasonal efficiency over the previous range of Daikin VRV systems. As a result, it already exceeds the standards of the Lot 1 Eco-design Directive, which is increasing the minimum efficiency requirements for air conditioners over 1kW once again in 1 January 01. At the heart of the latest system, existing VRV IV features such as variable refrigerant temperature and continuous heating during defrost are matched by a completely redesigned compressor, which is fully optimized to ensure high performance at part loads – the main operation mode throughout the year. The new compressor addresses a key issue that can occur during low load operation, which is that refrigerant leaks can occur from the high-pressure side to the low-pressure side in the compression chamber, resulting in loss of efficiency. In the new compressor, a back-pressure control port sends a small amount of high-pressure refrigerant from the compression chamber to the back of the scroll. This optimal separation of lower- and higher-pressure sides within the compression chamber boosts seasonal efficiency delivering a 15% increase in efficiency. The VRV IV+ also uses a four-side heat exchanger with a new capillary design for optimized refrigerant distribution, providing the smoothest performance in any system loading. The VRV IV+ delivers 15% higher average SEER. On an 8HP system, the SEER is as much as 38% higher with indoor ducts and 41% higher with indoor cassettes. In heating mode, the VRV IV+ delivers 13% higher SCOP on average, or 16% higher SCOP for an 8HP unit with indoor ducts.