초록 ▼

Refrigerant is circulated through a vapor compression system including a compressor, a condenser, an expansion device, and an evaporator. Cold condensate forms on the evaporator surfaces as the refrigerant accepts heat from an air stream. The cold condensate drips down from the evaporator coil and

Refrigerant is circulated through a vapor compression system including a compressor, a condenser, an expansion device, and an evaporator. Cold condensate forms on the evaporator surfaces as the refrigerant accepts heat from an air stream. The cold condensate drips down from the evaporator coil and collects in a condensate pan. In one example, the cold condensate is directed into a condensate heat exchanger to subcool the refrigerant exiting the condenser. In another example, the refrigerant exiting the condenser flows through a refrigerant line located in the condensate pan. In another example, the cold condensate is sprayed on the refrigerant line exiting the condenser or on the subcooling portion of the condenser. By utilizing the condensate for further subcooling of the refrigerant, system capacity and efficiency are enhanced. Various control techniques and condensate flow methods are also disclosed.

대표청구항 ▼

We claim: 1. A vapor compression system comprising: a condenser; an evaporator; an expansion device between the condenser and the evaporator; and a subcooling portion that facilitates subcooling of refrigerant flowing between the condenser and the expansion device using condensate that forms on the

We claim: 1. A vapor compression system comprising: a condenser; an evaporator; an expansion device between the condenser and the evaporator; and a subcooling portion that facilitates subcooling of refrigerant flowing between the condenser and the expansion device using condensate that forms on the evaporator, wherein the subcooling portion is a part of the condenser. 2. The system of claim 1, including a condensate pan associated with the evaporator for at least temporarily collecting the condensate and wherein the subcooling portion further includes a refrigerant line between the condenser and the expansion device and having at least a portion supported for heat exchange between the refrigerant in the refrigerant line and the condensate in the condensate pan. 3. The system of claim 2, wherein the portion of the refrigerant line is positioned to be at least partially immersed in the condensate in the condensate pan. 4. The system of claim 1, further including a heat exchanger that receives at least some of the condensate and further subcools the refrigerant flowing between the condenser and the expansion device. 5. The system of claim 4, including a flow control device that controls a flow of the condensate into the heat exchanger. 6. The system of claim 1, wherein the subcooling portion is a last stage of a condenser coil, and the system further includes a sprayer that sprays at least some of the condensate onto the last stage of the condenser coil. 7. The system of claim 1, wherein the subcooling portion is a last stage of a condenser coil, and the condensate flows onto the last stage of the condenser coil by gravity. 8. The system of claim 1, further including a refrigerant line between the condenser and the expansion device, wherein at least some of the condensate is directed onto the refrigerant line. 9. A vapor compression system comprising: a condenser; an evaporator; an expansion device between the condenser and the evaporator; a subcooling portion that facilitates subcooling of refrigerant flowing between the condenser and the expansion device using condensate that forms on the evaporator; a heat exchanger that receives at least some of the condensate and further subcools the refrigerant flowing between the condenser and the expansion device; a flow control device that controls a flow of the condensate into the heat exchanger; a condensate pan associated with the evaporator for at least temporarily collecting the condensate; a control that activates the flow control device; and a level sensor that detects an amount of the condensate collected in the condensate pan, wherein the control activates the flow control device to direct the condensate into the heat exchanger when the level sensor detects that the amount of the condensate collected in the condensate pan exceeds a threshold amount. 10. A method of subcooling refrigerant in a vapor compression system having a condenser, an evaporator and an expansion device between the condenser and the evaporator, the method comprising the step of: exchanging heat between condensate that forms on the evaporator and the refrigerant that flows between a subcooling portion of the condenser and the expansion device, wherein the subcooling portion is a part of the condenser. 11. The method of claim 10, including directing at least some of the condensate onto a refrigerant line extending from the subcooling portion of the condenser and to the evaporator. 12. The method of claim 11, including spraying the condensate on the refrigerant line. 13. The method of claim 11, including directing at least some of the condensate onto the refrigerant line by gravity. 14. The method of claim 11, including directing at least some of the condensate onto the subcooling portion of the condenser by gravity, wherein the subcooling portion is a last stage of a condenser coil. 15. The method of claim 10 including spraying the condensate on the subcooling portion of the condenser, wherein the subcooling portion is a last stage of a condenser coil. 16. The method as recited in claim 10, including collecting at least some of the condensate in a condensate pan, sensing an amount of the condensate collected in the condensate pan and directing at least some of the condensate onto a refrigerant line extending from the condenser and to the evaporator when the amount of the condensate collected in the condensate pan is above a threshold amount. 17. A vapor compression system comprising: a condenser; an evaporator; an expansion device between the condenser and the evaporator; a subcooling portion comprising a refrigerant line between the condenser and the expansion device that facilitates subcooling of refrigerant flowing between the condenser and the expansion device using condensate that forms on the evaporator; a condensate pan including a drain that is associated with the evaporator for at least temporarily collecting the condensate, wherein the refrigerant line has at least a portion supported for heat exchange between the refrigerant in the refrigerant line and the condensate in the condensate pan and the portion is at least partially immersed in the condensate in the condensate pan; a control; at least one of a temperature sensor and a level sensor, wherein the control opens the drain to purge the condensate from the condensate pan through the drain when the at least one of a temperature sensor and a level sensor detects a value above a threshold value. 18. The system of claim 17, wherein the at least one of a temperature sensor and a level sensor is a temperature sensor, the value is a temperature of the condensate and the threshold value is a threshold temperature, wherein the control opens the drain to purge the condensate from the condensate pan through the drain when the temperature sensor detects that the temperature of the condensate is above the threshold temperature. 19. The system of claim 17, wherein the at least one of a temperature sensor and a level sensor is a level sensor, the value is an amount of the condensate and the threshold value is a threshold amount of the condensate, wherein the control opens the drain to purge the condensate from the condensate pan through the drain when the level sensor detects that the amount of the condensate is above the threshold amount of the condensate. 20. A vapor compression system comprising: a condenser; an evaporator; an expansion device between the condenser and the evaporator; a subcooling portion that facilitates subcooling of refrigerant flowing between the condenser and the expansion device using condensate that forms on the evaporator, wherein the subcooling portion comprises a refrigerant line between the condenser and the expansion device; and a condensate pan associated with the evaporator for at least temporarily collecting the condensate, wherein the condensate flows from the condensate pan and onto the refrigerant line by gravity. 21. The system of claim 20, wherein the subcooling portion includes a heat exchanger that receives at least some of the condensate from the condensate pan and further subcools the refrigerant flowing between the condenser and the expansion device. 22. The system of claim 21 wherein the subcooling portion includes a sprayer that sprays at least some of the condensate onto the refrigerant line. 23. The system of claim 22, including a flow control device that controls a flow of the condensate to the sprayer. 24. A method of subcooling refrigerant in a vapor compression system having a condenser, an evaporator and an expansion device between the condenser and the evaporator, the method comprising the steps of: exchanging heat between condensate that forms on the evaporator and the refrigerant that flows between a subcooling portion and the expansion device; collecting at least some of the condensate in a condensate pan and directing the refrigerant through a conduit that is positioned to be at least partially immersed in the condensate collected in the condensate pan; controlling a drain in the condensate pan; and purging the condensate from the condensate pan through the drain when at least one of a temperature sensor and a level sensor detects a value above a threshold value. 25. The method of claim 24, wherein the at least one of a temperature sensor and a level sensor is a temperature sensor, the value is a temperature of the condensate, and the threshold value is a threshold temperature, the method including the step of sensing the temperature of the condensate collected in the condensate pan, wherein the step of purging the condensate from the condensate pan includes purging the condensate when the temperature is above the threshold temperature. 26. The method of claim 24, wherein the at least one of a temperature sensor and a level sensor is a level sensor, the value is an amount of the condensate, and the threshold value is a threshold amount of the condensate, the method including the step of sensing an amount of the condensate collected in the condensate pan, wherein the step of purging the condensate from the condensate pan includes purging the condensate when the amount of the condensate is above a threshold amount of the condensate.