SAV moves into high-efficiency hot water

SAV Valve Systems has introduced a heat-exchange module to produce domestic hot water direct from cold mains using heat from central boiler plant. It comprises a compact plate heat exchanger and differential-pressure control valve (DPCV). Cold water is heated directly, so no separate cylinder or calorifier is required. The unit is so efficient that an 80°C flow temperature is reduced to 15°C when the cold water is at 10°C — maximising the efficiency of condensing boilers. The system is also effective with a flow temperature of around 60°C, such as those associated with underfloor heating. These modules are available in sizes from 35 to 220 kW. When a hot-water outlet is opened, the change in system pressure is detected and all the flow in the heating circuit is diverted to DHW supply. Constant modulating control ensures energy is directed according to demand. The DHW valve in the module closes immediately demand ceases, largely preventing the formation of bacteria and limescale. The cold-water connection includes a dual-function ball valve, non-return and safety valves — so that backflow cannot occur. These heat-exchange modules are supplied fully assembled and pre-tested for fast installation.