Functional diagram

Everything under perfect control!

The HV unit meets all the demands that are placed on modern heating systems. State-of-the-art technology for all house technology needs in low-energy and passive houses.

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Components at a glance

1 - HV unit 12 - Condenser heat pump
2 - Outside air intake ventilation 13 - Exhaust air from room
3 - Geothermal heat exchanger (GHE) 14 - Supply air into room
3.1 - Defroster heater (alt. GHE) 15 - Heat storage tank KS-PWS 500-2
4 - Geothermal heat exchanger bypass 17 - Storage water supply
5 - Outside air for heat pump 18 - Hot water heat exchanger
6 - Fan exhaust air ventilation 21 - Solar heat exchanger
7 - Reverse flow duct heat exchanger 22 - Electric heating element
8 - Fan supply air ventilation 23 - Supply-air duct heater (optional)
9 - Summer bypass supply air 24 - Supply-air temperature limiter
10 - Fan heat pump 25 - Solar thermal system (optional)
11 - Evaporator heat pump 26 - fire place supply (optional)

Functional Description

Ventilation Module

The HV unit (1) provides the building with supply air and aspirates the contaminated air. Via the ventilation outside air connection (2) and by means of the supply-air fan (8), outside air is sucked into the building via a geothermal heat exchanger (3) laid in the ground. Via the geothermal heat exchanger the outside air is preheated in winter and precooled in summer. As an alternative to the geothermal heat exchanger an electric defroster heater (3.1) can be used that preheats the outside air in winter.
The fresh air is conducted through the reverse flow duct heat exchanger (7) and draws heat from the counterflowing exhaust air (13). Via the supply-air duct system the fresh air enters the living areas as supply air (14). In summer the fresh air can be channelled past the reverse flow duct heat exchanger. For this purpose the summer bypass flap (9) in the supply-air bypass duct is repositioned. With the optional geothermal heat exchanger bypass (4) the fresh air supply can be switched over. The fresh air can thus be supplied via the geothermal heat exchanger or directly via the outside air connection. In this way the fresh air is always aspirated at the optimum temperature.

Heat Pump

The exhaust air is conducted through the evaporator (11) (air-to-refrigerant heat exchanger) of the heat pump by means of the exhaust-air fan (6). In the evaporator the exhaust air delivers the remaining heat still contained in it to the refrigerant circuit heat pump. The heat pump draws heat energy from the exhaust air in the evaporator and delivers this directly to the storage water (17) in the condenser (12) (refrigerant-to-water heat exchanger) of the heat pump. In order to cover the complete heat requirement for heating purposes and domestic water needs, additional outside air (5) is directly aspirated and also conducted through the evaporator. In this process the additional outside air delivers heat energy to the refrigerant circuit heat pump. In the case where the supply-air and exhaust-air fan motors are not in operation, the volume flow required to operate the heat pump is aspirated by the outside air fan motor (10) alone. Because of this, the optimum volume flow is always conducted through the evaporator of the heat pump. In this way an optimum coefficient of performance of the heat pump for each operating state of the HV unit is ensured.

Heat Storage Tank

The storage tank (15) is heated via the heat pump and, where applicable, a solar thermal system (25) or water-conducting fire place. If the energy recovered from the heat pump and solar thermal system is not sufficient, the electric heating element (22) is switched on in a controlled manner. The energy recovered from the heat pump is supplied directly to the storage water (17) in the the condenser (12) (refrigerant-to-water heat exchanger) of the heat pump. The energy recovered from the solar thermal system is supplied via the heat exchanger (21). Via the domestic water heat exchanger (18) energy is removed and supplied to the tap connections in the building. The static heating surfaces and/or the hot water duct heater (23) in the supply air are connected directly to the storage tank.

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