System of energy recovery

The present invention relates to a system (100) for recovering energy exchanger, comprising a heat exchanger (10), characterized in that it further includes elements (30) pipe for the evacuation of smoke, and it further comprises a module (40) comprising a control transmitter (41) temperature, a controller (42) PID (proportional integral derivative) and a valve (43) three-way exchange, said module ( 40) control to obtain a predetermined amount of heat from exhaust gas to a module (50) of air-conditioning in absorption.