AIR CONDITIONING, AIR MOVEMENT AND VENTILATION SPECIAL FEATURES This month: Coanda effect in open ceilings; designing acoustics alongside ventilation London hotel chiller to save 179 tonnes of CO2 Part-load performance and low noise were key for hotel Five-star Biltmore Hotel in Londons Mayfair aims to save 179 tonnes of CO2 after installing new chillers as part of a 60m refurbishment. Carriers inverter-driven screw chillers replaced two ageing chillers that had reached the end of their working life at the hotel in Grosvenor Square. Challenges included limited space on the rooftop and strict controls on noise levels. There were also limitations on power, so careful assessment of start-up and peak loads was required. John Lam, head of the modernisation team that carried out the work, said: The customer was keen to minimise capital costs and maximise return on investment in a package that could be demonstrated to reduce the buildings carbon footprint. Two chillers with a combined cooling capacity of 1,460kW were installed within the 6.8m footprint available. The work included installation of integrated hydronic modules linked to the chillers variable speed drives, chiller sequencing control and factory-tted remote monitoring. The AquaForce Vision 30KAV used at the Biltmore Hotel An energy-use simulation highlighted that the building has a peak cooling load of 1,400kW and a base load of 700kW, requiring the chillers to operate for an average of 18 hours a day throughout the week at the 308-room hotel. It was calculated that the installation would use 20% less electrical power than the old models, delivering savings of 345,079kWh of electricity, equal to an annual carbon saving of 179 tonnes. Cold-storage unit adds capacity in peak production Cold-storage warehouses will be able to recover from breakdowns immediately thanks to a new, temporary air-cooled low-temperature air conditioning (AC) unit from Aggreko. Delivering 100kW of design cooling capacity at -22C air outlet temperature, the machine is a plug and play solution, housed in a 20ft container, that ensures stored refrigerated products are safeguarded in an emergency. Available as an air- or water-cooled unit, it can cool existing cold stores to temperatures as low as -40C, helping the cold storage and logistics industry to blastfreeze during peak production or in case of emergency. Interference with any cold-store warehouse is minimised because the unit is installed outside, increasing safety and avoiding costly installation fees. It also allows for temporary cooling during planned shutdowns, enabling the operation of the cold store to continue while a xed cooling installation is maintained or upgraded. The AC unit, which has a built-in management system, also has access to temporary power generators, so warehouses can be supplied with enough energy if no electricity is available from the grid. Panasonic wins iF Design Award Panasonic has received an iF Design Award from the International Forum Design, for its residential oor console air conditioner. Using R32 refrigerant, the console can operate in heating mode up to -15C, and cooling mode up to +43C. By generating hydroxyl radicals (OH), which oxidise chemicals and bacteria in the atmosphere, the units technology can work in heating or cooling operation to remove pollen, pollution and fungi from the air. It includes an internal dehumidier to limit the propagation of mould and bacteria. A CA controller app allows users to remotely control up to 10 sites, each with 20 indoor units. The unit is available in 2.5kW, 3.5kW and 5kW capacities for multi and single split, and 2kW for multi-split only. Air Design launches standard AHU range Air Design, a brand of air handling unit from Elta Group, has launched Pura, a new range of standard energy-recovery air handling units (AHUs). Using heat and/or coolth recovery technologies, the standard range of extruded aluminium, pentapost-frame air handling and energy-recovery units are available in double-decked, vertical or side-by-side, and horizontal arrangements, depending on the footprint. They also come equipped with a plate heat exchanger or rotor and an electric heater or low pressure hot water (LPHW) coil for heat provision. For cooling, a chilled water or refrigerant coil can be used. The units have achieved a casing air-leakage classication of L1 for minimum ingress of polluted air and have a lter bypass leakage ration of less than 1%. IT range is a cool solution Mitsubishi Electric has launched the s-MEXT air conditioner, which connects to the manufacturers power inverter outdoor units to create a full inverter split system. It is the rms rst packaged computer room air conditioning (CRAC) unit. The units are available in capacities from 6kW up to 42kW for applications where high sensible cooling and close control of temperature and humidity are required, such as small and medium-sized businesses (enterprise data centres) with onsite IT cooling requirements. They are also available in upow and downow variants, and occupy a small physical footprint, with pipe runs up to 100m. www.cibsejournal.com May 2019 41 CIBSE May19 pp41-42 Air Con News.indd 41 26/04/2019 17:11