Heat-exchange modules boost energy efficiency for apartment block

The energy efficiency of new luxury apartments in Poole has been raised above the SAP rating (BRE Standard Assessment Procedure) by providing heating and DHW services from central plant via an SAV heat-exchange module in each apartment. Acting as mechanical consultant for Westhaven, a new development by Kingsbury Homes in the Canford Cliffs area, Parker Heating devised a modular solution. Ian Parker explains, ‘The SAV modules have enabled us to combine the advantages of central boiler plant with those of a combi boiler. Safety and efficiency issues are resolved by the central plant, and hot water is available instantly in individual apartments — but only when required. There is no energy leak caused by storing hot water throughout the day that nobody needs.’ Hot water is supplied to the 14 apartments and penthouses from a modulating central boiler plant in the basement. There are three Viessmann boilers capable of supplying 18 to 180 kW. There are no DHW cylinders or calorifiers; instead, each apartment is equipped with an SAV heat-exchange module that can generate hot-water instantly. These modules are available in sizes from 35 to 220 kW and achieve major space savings compared with individual boilers in each dwelling. When there is a demand for DHW, energy is automatically diverted via the plate heat exchanger from heating circuits to hot water. Diverting energy to hot-water supply is more efficient, especially at times or peak demand. There is also a differential-pressure control valve in each module to maintain optimum pressure conditions in the heating circuit to enable individual room control via TRVs.