THERMAL CONDITIONING SYSTEM

A thermal conditioning system for a motor vehicle, including a refrigerant circuit. The refrigerant circuit includes a main loop, a first bypass branch, a third bypass branch, and a fourth bypass branch. The main loop includes, successively a compressor, a first heat exchanger configured to exchange heat with a first heat transfer fluid, a first expansion valve, a first refrigerant accumulation device, a second expansion valve, and a second heat exchanger. The first bypass branch includes a third expansion valve, and a third heat exchanger. The second bypass branch connects the main loop and the first bypass branch. The third bypass branch connects the main loop and the first bypass branch. The fourth bypass branch allows the refrigerant leaving the compressor to join the main loop, without passing through the first exchanger and the second expansion valve. The fourth bypass branch includes a fourth expansion valve.