| 摘要 |
The air conditioner circuit has an electrovalve (28) which, when functioning as a heater, completely isolates the part of the circuit having the external heat exchanger thus preventing frost formation when the exterior temperature is very low. The compressor (5) is connected to the main circuit via a transposing valve (23), directing refrigerant flow, in the cooling mode (36), through an exterior heat-exchanger (6,7), acting as condenser, in the engine compartment, an expansion valve (30), and another, interior, exchanger (8,9), acting as evaporator. An auxiliary exchanger (17,18), in the rear passenger area, effectively in parallel with the last-named, contributes to the cooling. By operating the transposing valve, the flow is reversed (37) to give heat pump operation. Circulation via the exterior exchanger (6,7) is prevented by an isolating valve (28). A non-return valve (31) by-passes the expansion valve (30). The interior main (8,9) and auxiliary (17,18) exchangers takes the roles of condenser and evaporator, respectively. |
