An NHS Surrey programme to upgrade heating and hot water systems across over 20 sites has seen the organisation standardise on new equipment from Hamworthy Heating.
Gary White, programme manager, Surrey Primary Care Trust (PCT), said: “Replacing ageing boilers and water heaters, we were looking to lower our energy bills and carbon emissions. Our Estates Department wanted to standardise boilers and equipment across the sites. Hamworthy’s diverse, energy-efficient product range enabled us to select the most suitable boiler and water heater for each application.” At the 20-bed Molesey Hospital, three existing gas-fired atmospheric boilers were replaced with two Purewell VariHeat 70 kW gas-fired condensing boilers. Two new Dorchester DR-FC Evo 30 direct-fired condensing water heaters (pictured in the plantroom with a Chesil pressurisation unit) provide ‘highly efficient hot water generation’. Hugo Jimenez, senior mechanical designer, MCA Consulting, who specified the equipment, said: “We chose to separate the heating and hot water due to the 24/7 demands placed on the system, and the requirement for critical hot water to reach temperature very quickly.” While the three atmospheric on/off boilers removed from the site gave a 123 kW total output, a 3:1 turndown ratio, and seasonal efficiencies of 78%, comparative figures for the two new condensing boilers are 140 kW, 7:1, and 95%. Hot water is now provided by the two condensing water heaters with a total continuous output of 1,260 litres/hour, thermal efficiencies of 98%, low NOx levels, and ‘superior controls’.
