Efficiency of a WHR system

WHR systems transfer the warmth of the extracted air to the cool outside air using a heat exchanger. That saves energy and prevents cold air flows. Modern WHR systems have an efficiency of over 95%. In the winter, with a room temperature of 21° Celsius, the outside air is preheated to 18° Celsius before being blown into the house. Besides energy saving, WHR ventilation also ensures a pleasant, fresh indoor climate all year long. That is healthy and comfortable.