Heat recovery in natural ventilation design of office buildings.

Heat recovery in ventilation systems for office buildings in cold climates is necessary for tworeasons:1. To obtain acceptable indoor thermal comfort by preheating of fresh air,2. To reduce ventilation energy lossThis paper describes a pilot system built in the laboratory of the Norwegian Building ResearchInstitute, NBI, based upon the concept of an advanced fan assisted natural ventilation systemwith heat recovery. The concept was developed by NBI.