This Series units use natural refrigerant R290 ( GWP=3) that offers many advantages over refrigerants traditionally used in heat pumps.With improved efficiency, as well as higher flow temperatures (70 degrees), is perfect for new and existing heating systems (including hybrid). 
Energy efficiency class of A+++ reduce the energy consumption of the outdoor unit. Using smart grids (SG ready), you can also take advantage of variable electricity prices and make additional savings. 
Works all the way down to minus 25 degrees, so you are guaranteed good and stable heat, even on the coldest days of the year.
Frequency controlled: The heat pump can run with different services. When the desired temperature is achieved, running it with a lower one; frequency/performance to reduce energy consumption.
With DC Inverter brushless fan motor that can be controlled so that the sound from the device reaches a satisfactory low level.
Intelligent defrosting technology that minimizes energy consumption.

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