DHW heat pumps for high hot water comfort

During operation, the DHW heat pump absorbs the heat from the recirculation air or the extract air and conveys it to the evaporator. It contains a refrigerant that heats up at low temperature before turning to vapour. Since the temperature of the vaporised refrigerant is not yet high enough to heat the water, this is followed by a compression process. In this process, the steam is conveyed to a current-driven compressor, which compresses it until the required temperature is reached.

In the final step, the heated refrigerant vapour transfers its thermal energy to the built-in DHW cylinder, cools down and condenses. The refrigerant liquid is then expanded at high pressure by an expansion valve while it continues to cool down considerably. Once the refrigerant is back in its initial state, the compression process can begin again.

Domestic hot water heat pumps can extract heat from either recirculation air, outdoor air or extract air. Suitable rooms for a recirculation air DHW heat pump include basements that have a constant and relatively high temperature during the winter months. During operation, the temperature in the basement is cooled by about two to four degrees. At the same time, the basement air is dehumidified. If the temperature differential between the heat source and the heating system is small, the domestic hot water heat pump from Viessmann works extremely efficiently.

Another option is for heat pumps to heat the domestic hot water with extract air. In this case, the top cover of the extract air heat pump is replaced by an extract air cover and the heat pump is coupled to the existing air distribution system. The heat pump is supplied with the warm extract air from several rooms, which allow it to provide good ventilation for an average detached house. The extract air that is cooled down during DHW heating is routed outdoors as exhaust air. To avoid negative pressure, outdoor air must be supplied via separate supply air elements. Ventilation mode is also possible without DHW heating.

Viessmann DHW heat pumps are designed for both mono mode and dual mode operation with a solar thermal system. In the dual mode version, the solar circuit pump is switched on or off electronically, with the aid of a temperature differential control. If the solar circuit pump is active, DHW heating is not produced by the heat pump. This ensures optimal use of free solar energy. In addition, the heat pump can make optimum use of self-generated power from a  photovoltaic system. Prepared for the use of solar energy

Viessmann DHW heat pumps are designed for both mono mode and dual mode operation with a solar thermal system. In the dual mode version, the solar circuit pump is switched on or off electronically, with the aid of a temperature differential control. If the solar circuit pump is active, DHW heating is not produced by the heat pump. This ensures optimal use of free solar energy. In addition, the heat pump can make optimum use of self-generated electricity from a  photovoltaic system.