Air-conditioning reject heat makes hot water

Air conditioning, Daikin, heat recovery, DHW

Daikin’s HXHD hydrobox makes it possible to recover heat from a VRVIII air-conditioning system to produce domestic hot water or provide heating to radiators or underfloor heating when combined with the REYAQ-P heat-recovery system (pictured). During Winter, when not enough recovered heat is available, the outdoor unit takes up the difference to produce DHW 17% more efficiently than a traditional gas-boiler solution.

The hydrobox includes all the connections, pumps, filter and valves to connect to a water circuit. It can be stacked with a DHW tank. Intelligent control of water temperature eliminates the need for a mixing valve by producing precisely the required leaving water temperature. Alternatively, a weather-compensated floating setpoint can be established for space heating.

Leaving water temperatures of up to 80°C can be achieved without an auxiliary heater. Hot-water tanks with capacities from 200 to 500 l are available.

For more information on this story, click here: Nov 2011, 172
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