Refrigeration system and method of operating a refrigeration system

1. A method of operating a filling system which is configured for transferring a refrigerant to a refrigeration system, the filling system including a receiver for collecting a refrigerant-air-mixture, the method comprising:

determining a saturation pressure of the refrigerant at actual environmental conditions;

determining air pressure of the refrigerant-air-mixture within the receiver; and

at least one of stopping operation of the system, and issuing an alarm, if the air pressure of the refrigerant-air-mixture within the receiver exceeds the saturation pressure of the refrigerant by more than a predetermined margin or if a change of the air pressure of the refrigerant-air-mixture within the receiver over time exceeds a predetermined margin.

2. The method of claim 1 , wherein the step of determining the saturation pressure of the refrigerant includes the step of determining a temperature of the refrigerant.

3. The method of claim 1 , wherein the step of determining the air pressure of the refrigerant-air-mixture within the receiver includes:

determining total pressure within the receiver;

determining refrigerant pressure within the receiver; and

determining the air pressure of the refrigerant-air-mixture from the total pressure and the refrigerant pressure.

4. The method of claim 3 , wherein the total pressure within the receiver is determined using a pressure sensor.

5. The method of claim 3 , wherein the refrigerant pressure is determined by measuring a temperature of the refrigerant-air-mixture.

6. The method of claim 1 , wherein operation of the refrigeration system is stopped if the air pressure of the refrigerant-air-mixture within the receiver exceeds the saturation pressure of the refrigerant by more than a predetermined first margin, and an alarm is issued if the air pressure of the refrigerant-air-mixture within the receiver exceeds the saturation pressure of the refrigerant by more than a predetermined second margin.

7. The method of claim 6 , wherein the first margin is smaller than the second margin.

8. The method of claim 6 , wherein the first margin is 1.0 bar.

9. The method of claim 6 , wherein the second margin is 1.7 bar.

10. The method of claim 2 , wherein the step of determining the temperature of the refrigerant comprises determining the temperature of the refrigerant disposed within the receiver.

11. The method of claim 1 , further comprising venting the receiver by dispensing an excessive amount of the refrigerant from the receiver to the external environment.

12. The method of claim 11 , further comprising switching off an electrical device in the external environment.

13. The method of claim 1 , further comprising delivering the refrigerant from a bottle to a heat suction accumulator, and heating the refrigerant in the heat suction accumulator so as to vaporize the refrigerant.

14. The method of claim 13 , further delivering the vaporized refrigerant from the heat suction accumulator to the compressor, and compressing the vaporized refrigerant to an increased pressure level.

15. The method of claim 14 , further delivering the compressed refrigerant from the compressor to a heating coil in the heat suction accumulator, and transferring heat from the compressed refrigerant to the refrigerant received from the bottle.

16. The method of claim 15 , further delivering the compressed refrigerant from the heating coil in the heat suction accumulator to the receiver, and transferring heat from the compressed refrigerant to the refrigerant received from the bottle.

17. A filling system for transferring refrigerant to a refrigeration system, the filling system comprising:

a receiver for collecting a refrigerant-air-mixture;

a pressure sensor for measuring pressure in the receiver;

a temperature sensor for measuring a temperature of the refrigerant-air-mixture in the receiver; and

a control unit configured to determine based on the pressure and the temperature respectively measured by the pressure sensor and the temperature sensor a saturation pressure of the refrigerant and the air pressure of the refrigerant-air-mixture within the receiver, and to at least one of stop the operation of the filling system and issue an alarm, if the air pressure of the refrigerant-air-mixture within the receiver exceeds the saturation pressure of the refrigerant by more than a predetermined margin or if a change of air pressure of the refrigerant-air-mixture within the receiver over time exceeds a predetermined margin.

18. The filling system of claim 17 , further comprising a venting valve fluidly communicating with the receiver and configured to dispense an excessive amount of the refrigerant from the receiver to the external environment.