The monitored performance of the combination of balanced ventilation with post-conditioning by an air-to-air heat pump

A balanced ventilation system can be combined with an air-to-air heat pump. Such system combines the refreshment of the air in a house with heating and cooling of the fresh air in order to influence the indoor conditions like temperature and humidity. Depending on the season in the year, various modes are used to deliver fresh air and condition the incoming air to the desired levels.  
Field tests with such a ventilation system were carried out in houses in Luxembourg and in Italy. The monitored data has been analysed to give meaningful views of the performance. Correlations between supply temperatures and outdoor temperatures show modes of the system with heat recovery, cold recovery or passive cooling combined with active heating or active cooling when needed. The data shows that the system is first attempting to heat or cool with passive means, after which active heating or cooling is used when necessary. 
The desired indoor temperatures are based on a temperature profile as a function of the prevailing mean outdoor temperature, following the adaptive comfort guidelines. The resulting thermal output as well as the required electrical consumption are given. Energy signatures show the daily thermal output as a function of the daily averaged outdoor temperatures. These energy signatures also show the resulting heating season, intermediate season and cooling season. The threshold of the heating and cooling season is dependent on the demands of the residents, but also on geographical location, orientation of the house and insulation properties.