Patent ID: 7182129

Claim:
A device for heating and/or air conditioning the passenger compartment of a motor vehicle, comprising an engine-cooling loop in which a heat-carrying fluid circulates for taking up heat from the engine and returning the heat to an air heater; a heat-pump loop in which a refrigerant fluid circulates, said heat-pump loop containing a compressor, a first evaporator constituting a cold source of the heat pump at which the refrigerant fluid takes up heat from the surroundings, and a first condenser constituting a hot source of the heat pump at which the refrigerant fluid gives up heat, the first condenser being integrated into the engine-cooling loop upstream of the air heater, the device further comprising an air-conditioning branch containing a second condenser and a second evaporator, the air-conditioning branch having an upstream end connected to the heat-pump loop downstream of the compressor, and a downstream end connected to the heat-pump loop upstream of the compressor, and a switching device making it possible to make the refrigerant fluid circulate either in the air-conditioning branch, or in the heat-pump branch, is such a way as to form a heat-pump loop, and further comprising a modular casing containing the first evaporator, first valve system of the first evaporator for controlling the quantity of heat-carrying fluid which passes through the first evaporator an anti-return valve upstream of the evaporator, the first condenser, second valve system of the first condenser for controlling the quantity of heat-carrying fluid which passes through the first condenser, the switching device and a pressure-reduction means of the heat-pump loop for reducing the pressure of the refrigerant fluid between the first condenser and the first evaporator, wherein said first valve system is operatively connected with said second valve to control an intake pressure of said compressor.