A landmark 1980s ‘head office’ building in Richmond, London, underwent a substantial £5 million refurbishment that included raising its Energy Performance Certificate rating from E to B and achieving a BREEAM Excellent rating. This also meets the borough targets for a 40% reduction in carbon emissions. In selecting the Kew Road building’s new heating and cooling system, noise criteria and line-of-sight constraints ruled out chillers and air-cooled VRV outdoor units. The former UK headquarters of Pepsi Cola was acquired by the Low Carbon Workplace and is now home to the leading online marketplace for creative small businesses, notonthehighstreet.com.
The chosen system for air conditioning was Daikin water-cooled VRV, which could be contained – out of sight and earshot – in a plant room. Six systems totalling 13 condensers generate the total heating and cooling requirement for all floors and an air curtain in the lobby. Another four condensers serve two air handling units. Two low-height, low-noise dry air coolers reject heat from the water loop. A 546kW boiler provides hot water for the building and heat injection to maintain a fixed 40oC flow to the Daikin VRV-W condensers during cold weather. To save space, the condensers were racked, two high.
Water-cooled VRV condensing units
Slim concealed ceiling unit
Intelligent Touch Manager
The solution satisfied the requirements for heating and cooling plant without compromising design – or the lettable floor area. Stephen Reynolds of Thornton Reynolds, mechanical and electrical consultant on the refurbishment, says: “VRV-W ticks all the boxes at 63 Kew Road, satisfying environmental regulations and efficiency requirements – while providing the same standards of comfort expected from air-cooled VRV systems.” VRV-W also offered the efficiency advantage of two-stage heat recovery ¬– within each system and between systems on the water loop. This two-stage recovery substantially improves overall energy efficiency especially in situations where cooling is required even in winter.