Device for the thermal control for a motor vehicle passenger compartment

The regulated heater (10) for a motor vehicle interior has a first circuit for a coolant with an engine (14) and a cooling reservoir (16). There is a second circuit (20) for a heat exchange liquid with a condenser (24) in thermal exchange with the first circuit, a release valve (32) and an evaporator (34) in a ventilation duct to the vehicle interior. The second circuit also has a compressor (36) and a heating radiator (22). Flaps (45,46) are provided to vent heat from the interior when the heating radiator functions as a heat pump.