Thermal conditioning system comprising: - a heat-transfer liquid circuit having: a main circulation loop, a secondary loop, a first branch and a second branch, - a refrigerant fluid circuit comprising a main loop for circulation of refrigerant fluid having the following in succession in a direction of circulation of the refrigerant fluid: -- a compression device, -- a first bifluid exchanger arranged both on the refrigerant fluid circuit and on the main loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the main loop, -- a second bifluid exchanger arranged both on the refrigerant fluid circuit and on the main loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the main loop, -- a first expansion device, -- a third bifluid exchanger arranged both on the refrigerant fluid circuit and on the secondary loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the secondary loop, wherein the first branch of the heat-transfer liquid circuit links a first connection point disposed on the main loop to a second connection point disposed on the main loop, the first branch being configured such that the heat-transfer liquid at the outlet of the first bifluid exchanger returns to an inlet of the first bifluid exchanger without passing through the second bifluid exchanger, the first branch having a second heat exchanger configured to exchange heat with a second air stream, and wherein the second branch of the heat-transfer liquid circuit links a third connection point disposed on the first branch downstream of the second heat exchanger to a fourth connection point disposed on the main loop upstream of the second bifluid exchanger, the second branch having a third heat exchanger configured to exchange heat with the second air stream. - a heat-transfer liquid circuit having: a main circulation loop, a secondary loop, a first branch and a second branch, - a refrigerant fluid circuit comprising a main loop for circulation of refrigerant fluid having the following in succession in a direction of circulation of the refrigerant fluid: -- a compression device, -- a first bifluid exchanger arranged both on the refrigerant fluid circuit and on the main loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the main loop, -- a second bifluid exchanger arranged both on the refrigerant fluid circuit and on the main loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the main loop, -- a first expansion device, -- a third bifluid exchanger arranged both on the refrigerant fluid circuit and on the secondary loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the secondary loop, -- a compression device, -- a first bifluid exchanger arranged both on the refrigerant fluid circuit and on the main loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the main loop, -- a second bifluid exchanger arranged both on the refrigerant fluid circuit and on the main loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the main loop, -- a first expansion device, -- a third bifluid exchanger arranged both on the refrigerant fluid circuit and on the secondary loop of the heat-transfer liquid circuit so as to enable an exchange of heat between the refrigerant fluid and the heat-transfer liquid in the secondary loop, wherein the first branch of the heat-transfer liquid circuit links a first connection point disposed on the main loop to a second connection point disposed on the main loop, the first branch being configured such that the heat-transfer liquid at the outlet of the first bifluid exchanger returns to an inlet of the first bifluid exchanger without passing through the second bifluid exchanger, the first branch having a second heat exchanger configured to exchange heat with a second air stream, and wherein the second branch of the heat-transfer liquid circuit links a third connection point disposed on the first branch downstream of the second heat exchanger to a fourth connection point disposed on the main loop upstream of the second bifluid exchanger, the second branch having a third heat exchanger configured to exchange heat with the second air stream.