Refrigeration unit apparatus and method

A method of controlling a refrigeration system, the refrigeration system including a compressor, a condenser coupled to the compressor, a heat exchanger coupled to both the condenser and the compressor, an evaporator coupled to both the heat exchanger and the compressor, and an electronic expansion valve, wherein an input of the valve is coupled between the condenser and the heat exchanger, and an output of the valve is coupled to the compressor, the method comprising:

• determining the power required to operate the compressor based on the measurement of system parameters;
• comparing the power required to a threshold value;
• and
• adjusting the flow of refrigerant through the electronic expansion valve in order to keep the power required below the threshold value.

A refrigeration system comprising:

• a refrigerant circuit including a compressor, a condenser coupled to the compressor, a heat exchanger coupled to the condenser and the compressor, and an evaporator coupled to the heat exchanger and the compressor;
• an electronic expansion valve, an input of the valve coupled between the condenser and the heat exchanger, an output of the valve coupled to the compressor;
• a first sensor and a second sensor positioned between the compressor and the condenser, the first sensor sensing temperature and the second sensor sensing pressure;
• and
• a microprocessor coupled to the valve and to the first and second sensors and programmed to control the flow of refrigerant through the valve.

A refrigeration system comprising:

• a first fluid path serially including a compressor, a discharge line, a condenser, a heat exchanger input line, a heat exchanger, a first heat exchanger output line, a throttling device, an evaporator, and a suction line;
• a second fluid path serially including the compressor, the discharge line, the condenser, the heat exchanger input line, an electronic expansion valve, a heat exchanger chamber, and a second heat exchanger output line;
• a first sensor and second sensor coupled to the discharge line, the first sensor sensing temperature and the second sensor sensing pressure;
• and
• a microprocessor coupled to the first and second sensors and the electronic expansion valve and programmed to control the flow of refrigerant fluid through the second fluid path.