Heat recovery units are ideal for use in houses, small offices and similar spaces – with an optimum exchange programme: the ventilation unit guides air extracted from the kitchen and bathroom to the outside. Fresh outdoor air is drawn into the unit via the pipe system. Here up to 88 % of the heat from the extract air is transferred to the supply air via a heat exchanger, which is then supplied back to the living and sleeping quarters.
Ventilation systems with heat recovery offer users a high degree of living comfort thanks to temperaturecontrolled and clean air. Here, important criteria are cleanliness, heating and humidity. Systemair has an eye on the future too. The potential for energy-saving exceeds even future requirements.
Considering the many advantages, your customers' decision shouldn't be whether to use heat recovery or not, but just which type of heat recovery to use.
A perfect exchange and a perfect indoor climate – the most important advantages of units with heat recovery
A rotary heat exchanger ensures both heat and moisture recovery. The constant turning of the rotor enables heat to be transferred continuously. In winter, the heat from the extract air is transferred to the cold filtered outdoor air. In summer, the reverse effect is used: the warm outdoor air is cooled by the colder extract air and the heat stays outside. A rotor can achieve sensible efficiencies of more than 85 per cent, and performs most strongly in climates down to around -20 °C. Here it is able to generate maximum heat recovery without any frost protection at all. Thanks to moisture recovery, the rotary heat exchanger also ensures perfect room humidity and an optimum indoor climate at any time of year – not too humid and not too dry.
A counter flow heat exchanger is for transferring heat. The filtered supply air and the used extract air are completely separated from each other. Therefore, moisture is not transmitted and must be removed. A counter flow heat exchanger can make best use of its high efficiency – up to 90 per cent – if the outside temperature does not fall (or falls only briefly) below its specific frost point (-3 °C at 90% efficiency). Then, frost protection is unnecessary and, due to the mild climate (not colder than around -3 °C), the indoor climate does not become too dry, even without the transfer of moisture. Additional frost protection is required at temperatures of less than -3 °C . This can be implemented using a brinegeothermal heat exchanger or an electric preheater