METHOD AT VENTILATION UNIT WITH HEAT RECOVERY, AND VENTILATION UNIT WITH HEAT RECOVERY

摘要

The invention relates to a method at a ventilation unit with heat recovery, and a ventilation unit. Outside air (3) is led via the inlet side of a heat exchanger (6) into a building as supply air flow (1 ) and exhaust air (2) is guided via the exhaust side of the same heat exchanger (6) out of the building as extract air (4), whereby heat contained in the exhaust air is transferred in the heat exchanger (6) to heat the supply air. The freezing of the exhaust side of the heat exchanger (6) is monitored by means of an electromagnetic radiator apparatus and antifreezing functions are initiated, if necessary. Electromagnetic radiation is guided from the outside of the heat exchanger (6) through the heat exchanger (6) and further out of the heat exchanger (6).