The University Center for Energy Efficient Buildings of the Czech Technical University is working on the development of a residential ventilation unit, which makes it possible to control the temperature of the incoming air all year round without the necessary support of cooling and heating systems. Currently, a functional sample is ready, which predominantly uses the technology of the future prototype.
The current solution designed by the Indoor Environment Laboratory and the research team Monitoring and Control of Smart Buildings of the Czech Technical University UCEEB represents a compact residential ventilation unit with a low height for easy installation, for example on a toilet. The highest air flow is 150 m3/h. As part of the project, many variants of the active exchanger and the overall configuration of the ventilation unit were designed and tested.
The residential ventilation unit uses a pair of heat exchangers to ensure its function. The first is a highly efficient heat recovery plate heat exchanger, the second is an active heat exchanger using thermoelectric modules. With this exchanger, the unit provides heating and cooling of the ventilation air.
The resulting solution uses a counter-flow arrangement through aluminum exchangers, which appropriately distribute the heat flow from the individual modules and create an increased heat exchange surface for heating and cooling the air. At the same time, a power supply regulator for thermoelectric modules is being developed, which is key to achieving high efficiency in the entire operating range.
With proper control, the unit achieves an increase in the temperature of the ventilation air by 10 K above the temperature of the exhaust air in winter mode. In summer mode, it achieves a reduction of the outdoor air temperature by up to 9 K. The EER of the entire ventilation unit during cooling is 0.6 to 2.3.
Research and development within the project Vzduchotechnická jednotka s termoelektrickým chlazením a ohřevem was supported by the OP PIK Application program.