A refrigeration system comprising: a chamber comprising a structure defining a work space having air; a heat exchanger positioned to communicate with the air in the work space; a compressor coupled to the heat exchanger and producing a hot fluid; a condenser coupled to the compressor and producing a liquid; a throttle valve coupled to the condenser and producing a cold fluid; a controller for controlling a mixture of cold fluid and hot fluid entering the heat exchanger, wherein the heat exchanger is an evaporator; and a hot fluid line connecting an output of the compressor with an input of the evaporator; characterized in that the controller includes a temperature-humidity mode in which the controller is programmed to control a flow rate of cold fluid by adjusting a control valve, which cold fluid is mixing with a stream of the hot fluid, and programmed to determine a temperature of air in the chamber, and if the temperature of air in the chamber is greater than a desired temperature range, the controller is programmed to increase the flow rate of cold fluid mixing with the hot fluid by a slight increment, said slight increment being designed to control a temperature differential between the mixture and air in the work space in order to control condensation formation on the heat exchanger so as to limit loss of humidity in the air in the work space, programmed to monitor the temperature of air in the chamber, and programmed to determine whether the temperature of air in the chamber has decreased, and if the temperature of air in the chamber has not decreased, the controller is programmed to further increase the flow rate of cold fluid mixing with the hot fluid by another slight increment and programmed to continue monitoring the temperature of air in the chamber, determining if the temperature of air in the chamber has decreased, and continuing increasing the flow rate of the cold fluid mixing with the hot fluid by slight increments if the temperature of air in the chamber has not decreased until a decrease in temperature is achieved, thereby the controller is controlling a ratio of cold fluid and hot fluid in the mixture to limit a temperature differential between the mixture and air in the work space in order to limit condensation formation on the evaporator. a chamber comprising a structure defining a work space having air; a heat exchanger positioned to communicate with the air in the work space; a compressor coupled to the heat exchanger and producing a hot fluid; a condenser coupled to the compressor and producing a liquid; a throttle valve coupled to the condenser and producing a cold fluid; a controller for controlling a mixture of cold fluid and hot fluid entering the heat exchanger, wherein the heat exchanger is an evaporator; and a hot fluid line connecting an output of the compressor with an input of the evaporator; characterized in that the controller includes a temperature-humidity mode in which the controller is programmed to control a flow rate of cold fluid by adjusting a control valve, which cold fluid is mixing with a stream of the hot fluid, and programmed to determine a temperature of air in the chamber, and if the temperature of air in the chamber is greater than a desired temperature range, the controller is programmed to increase the flow rate of cold fluid mixing with the hot fluid by a slight increment, said slight increment being designed to control a temperature differential between the mixture and air in the work space in order to control condensation formation on the heat exchanger so as to limit loss of humidity in the air in the work space, programmed to monitor the temperature of air in the chamber, and programmed to determine whether the temperature of air in the chamber has decreased, and if the temperature of air in the chamber has not decreased, the controller is programmed to further increase the flow rate of cold fluid mixing with the hot fluid by another slight increment and programmed to continue monitoring the temperature of air in the chamber, determining if the temperature of air in the chamber has decreased, and continuing increasing the flow rate of the cold fluid mixing with the hot fluid by slight increments if the temperature of air in the chamber has not decreased until a decrease in temperature is achieved, thereby the controller is controlling a ratio of cold fluid and hot fluid in the mixture to limit a temperature differential between the mixture and air in the work space in order to limit condensation formation on the evaporator.