New Models Are Smaller, Lighter And More Energy Efficient

Mitsubishi Electric has launched a new series of water-cooled VRF air conditioning systems with a line up that offers an industry-leading COP of 6.06 in heating and 5.71 in cooling, whilst delivering an average 20% increase in efficiency over previous models.

The new WY / WR2 YHM range is now available and comes in a modular system with units that are 40% shorter and half the volume ratio compared to the previous model.

Available in both a WY (Heat pump) and WR2 (Heat recovery) option, the units deliver from 8HP to 24HP and have a lower weight, reduced noise and increased maximum pipe lengths. The company is also planning to launch a triple-module WY system early in 2010 which will deliver up to 36HP.

“We have completely overhauled the entire range of water-cooled systems in just about every area,” explained Philip Ord, Product Marketing Manager. “These are smaller, quieter, more flexible, lighter, easier to install and maintain and offer even higher energy efficiency.”

The YHM range has been redesigned to allow for even more flexibility in design, with the ability to connect to up to 50 indoor units, coupled with easier maintenance, including front panel access to all printed circuit boards and an average weight decrease of 25%.

The range offers one reduced chassis size combined with the ability to link two systems together with a new twinning kit, and comes with a whole host of new features including rotation, backup and automatic refrigerant status check.

The height has been reduced by 40% from 1,800mm to 1,100mm and the width by 11% from 990mm to 880mm. The depth remains 550mm, which gives an overall volume ratio that is 52% the size of the old model.

In the two-module systems, which need a new twinning kit, the models are 53% of the volume ratio of the previous model.

All units offer low noise levels and the range is designed to be installed inside a building. The models also offer full inverter control from 20 – 100%, which means that the system will run at part load for the majority of the time improving efficiency whilst also keeping noise levels to an absolute minimum. The PQRY-P250YHM-A is now only 49dBA in low noise mode – a reduction of 3dBA over previous models.

“A new inverter scroll compressor helps improve efficiency and a new control box design improves both the reliability and ease of maintenance,” added Ord. “In addition, the two plate heat exchangers reduce the overall size and improve the efficiency further.”

In addition to helping shrink the all-round size and increase performance, the dual plate refrigerant to water heat exchangers offers better efficiency at low water temperatures (-5ºC) and makes the system ideal for ground source applications.

The systems are connectable to all standard City Multi indoor units and the total piping length has been increased to 500m for the 2-module system, with the distance between the outdoor and the furthest indoor increased to 165m.

In the dual-module system, the load is balanced between the units, with the first module taking the initial load (20-50%) for a set time after which the second module takes over this initial load.

This also allows the system to carry on if one of the modules fails, giving time for the unit to be repaired without a full loss of operation.

“As more building owners look for energy efficient ways of heating, cooling and ventilating their premises to comply with increasingly tough legislation, the opportunities for systems that reliably deliver COPs of more than 5 will grow,” Ord added.