Air separator within a solar air collector

A solar air-heating system for heating indoor air from a building, the system comprising:

• a glazed solar air collector adapted to be mounted to a building wall of the building, the glazed solar air collector comprising:
• a front glazing transparent to solar radiation, the front glazing having opposed front and back faces, the front face of the front glazing forming an external surface of the glazed solar air collector and being directly exposed to the ambient;
• a solar radiation absorber disposed behind the front glazing for absorbing solar radiation passing through the front glazing;
• a front plenum defined between the back face of the front glazing and an opposed front face of the solar radiation absorber;
• a back plenum defined between the solar radiation absorber and the building wall, the front plenum and the back plenum fluidly connected through perforations defined in the solar radiation absorber;
• and
• an internal air flow separator extending across the back plenum, the internal air flow separator dividing the back plenum into an inlet chamber and an outlet chamber, the inlet chamber and the outlet chamber fluidly connected via the front plenum;
• the inlet chamber having an air inlet for receiving air from inside the building, the outlet chamber having an air outlet for discharging heated air back into the building, the front plenum having a smaller air exchange interface with the inlet chamber than with the outlet chamber.