A heat pump and air conditioning system for a vehicle that has at least one coolant loop selectively connecting an engine cooling system with a heater core, a first coolant / refrigerant heat exchanger, and / or a second coolant / refrigerant heat exchanger, in order to warm a passenger compartment of the vehicle. The system also includes a refrigerant loop that includes a first expansion device between a condenser and evaporator, and a second expansion device between the first coolant / refrigerant heat exchanger and the second coolant / refrigerant heat exchanger. The refrigerant loop provides for cooling of the passenger compartment of the vehicle, as well as operating as a heat pump, together with the at least one coolant loop, to provide heat to the vehicle passenger compartment.