Refrigeration Circuit and Method of Operating a Refrigeration Circuit
The invention relates to a refrigeration circuit having a mono- or multi-component refrigerant circulating therein, said refrigeration circuit comprising at least one expansion device. According to the invention, the expansion device is provided in the form of at least two valves (a, b, c, d) connected in parallel. Furthermore, the invention relates to a method of operating such a refrigeration circuit. Said method is characterized in that, in case of a defect of one of the valves (a, b, c, d) connected in parallel, said defective valve is taken out of operation and the or at least one of the additional valves ensures the control operation of the refrigeration circuit.
1 . A refrigeration circuit having a mono- or multi-component refrigerant circulating therein, said refrigeration circuit comprising at least one expansion device,
characterized in that said expansion device is provided in the form of at least two valves (a, b, c, d) connected in parallel.
2 . A refrigeration circuit according to claim 1 , wherein said expansion device is arranged upstream of an injection valve (e) of a heat exchanger (B).
3 . A refrigeration circuit according to claim 1 , wherein the expansion device is arranged upstream of a refrigerant collecting container (A).
4 . A refrigeration circuit according to claim 1 , wherein the at least two valves (a, b, c, d) connected in parallel are high-pressure control valves.
5 . A refrigeration circuit according to claim 1 , wherein the high-pressure control valves are adapted to expand a refrigerant from a high pressure, which is between 45 and 120 bar, to an intermediate pressure between 30 and 50 bar.
6 . A refrigeration circuit according to claim 1 ,
characterized in that valves (a, b, c, d) employed are of continuous control type and/or non-continuous control type.
7 . A refrigeration circuit according to claim 1 ,
characterized in that at least one of the valves (a, b, c, d) is a magnetic valve.
8 . A refrigeration circuit according to claim 1 , in which at least two valves are magnetic valves,
characterized in that the magnetic valves are arranged in a valve block.
9 . A refrigeration circuit according to claim 1 ,
wherein the refrigerant is carbon dioxide.
10 . A refrigeration circuit according to claim 1 ,
wherein the at least two vales (a, b, c, d) connected in parallel have different Kv values.
11 . A method of operating a refrigeration circuit according to claim 1 ,
characterized in that, in case of a defect of one of the valves (a, b, c, d) connected in parallel, said defective valve is taken out of operation and the or at least one of the additional valves ensures the control operation of the refrigeration circuit.
12 . A method according to claim 11 ,
wherein said refrigeration circuit is operated in supercritical or transcritical manner.
13 . A method according to claim 11 ,
wherein different flow rates are realized by combination of non-continuous control magnetic valves with different Kv values.