Croydon Landmark Building
Daikin Water Cooled VRV Air Conditions Refurbished Croydon Landmark Building
Carolyn House is a '60s built, 17 storey, multi tenanted office complex in Dingwall Road, Croydon, where it still maintains its commanding presence on the town's commercial skyline. Over the last few years, as and when leases expired, owners Knowle (Croydon) Ltd have ordered refits to a number of individual floors. The most recent of these commenced in Autumn last year - to the 15th, 10th and 11th floors and includes new building services, designed by consultants, Watkins Payne Partnership, Sunbury on Thames, Middlesex. A major component of these services is 'state of the art' Daikin VRV-WII water cooled heat recovery air conditioning, installed by specialist air conditioning contractors, EPM Air Conditioning, Cannock, Staffordshire.
Three 30HP VRV-WII systems serve the upgraded floors via condensing units housed in purpose designed services cupboards located on the same floors. Each condensing unit is connected by a two pipe flow and return water circuit to existing LTHW boiler plant and a heat rejection dry cooler at roof top level. Water from mains is supplied via a pressurisation unit to the circuit at temperatures of 30°C (Winter) and 32°C(Summer). Liquid/gas refrigerant lines link the condensing units with the 14 or so Daikin FXSQ concealed ceiling indoor units installed per floor.
Nominal capacities of these units vary between 4.5kW cooling/5.0kW heating and 7.1kW cooling/8.0kW heating according to their respective location at the building's southern or northern facades.
During the heating cycle, heat is absorbed from the water circuit and transmitted via a plate heat exchanger within the condensing unit casing to the indoor fan coil units. Conversely, during cooling, heat is rejected to the water circuit and exhausted to atmosphere by the dry cooler. Heat recovery is achieved by utilising heat absorbed from the water circuit for indoor units in heating mode and rejecting heat to the water circuit from indoor units in cooling mode.
Internal design temperatures are 22°C +/- 1degC in Summer and 24°C +/- 2degC in Winter. Cooling and heating loads per floor are approximately 60kW and 32kW respectively. Tempered fresh air ventilation is provided by two Daikin VAM heat reclaim units per floor, which modulate the temperature and humidity of the incoming air and match it the prevailing indoor conditions.
A balance is thereby achieved between indoor and outdoor ambients, enabling the cooling and heating loads placed upon the VRV-WII systems to be reduced by a significant amount.
All VRV-WII and VAM systems are controlled via a Daikin I-manager air conditioning management system that uses the independent, Daikin high speed, multi transmission Dill-NET high-speed data communication system.
Based around a centralised PC controller, the Carolyn House I-manager will ensure maximum energy efficient operation of the air conditioning installation via precise monitoring and more precise control. It will measure room temperature and automatically control system changeover between cooling and heating cycles, limit maximum and minimum temperatures and eliminate overcooling. It will also provide information on and regulate electrical power consumption and provide a host of other useful system management data. Furthermore, in the event of the central computer crashing, the system will continue its control and management functions for about 48 hours.
