Thermodynamic heating and ventilating system - has controlled by=pass round extract air compressor to maintain constant ventilation rate

摘要

A fan (12) extracts a constant volume of air from a building or other enclosure (L). The bulk of it is compressed in a compresser(1) which raises its temperature. It is then cooled in a heat exchanger(41, 42) in which it gives the heat up to fresh air drawn from the atmosphere (A) and delivered to the building (L) by a fan (11). The heat output is controlled by variation of the speed of the compressor. When the heat output is reduced the volume flow through the compressor is also reduced. a regulating valve (13) then partially opens a bypass (14) which discharges extracted air directly to atmosphere. The reduced flow through the compressor does not therefore reduce the ventilation rate of the building (L).