Refrigeration system

A defrost system for a refrigeration device having a first cooling system having a first loop in thermal communication with a second cooling system having a cooling element and first flow path configured for flow of a coolant chilled by the first cooling system during a cooling mode, the defrost system comprising:

• a second flow path coupled to the first flow path;
• a heat exchanger coupled to the second flow path and in thermal communication with the coolant and adapted to transfer a quantity of heat from an air source to the coolant;
• a control system operable to permit flow of the coolant through the second flow path to the heat exchanger for transferring heat from the air source to the coolant during a defrost mode and operable to substantially prevent flow through the second flow path and the heat exchanger during a cooling mode;
• so that the cooling element receives a flow of warmed coolant from the second flow path during the defrost mode and receives a flow of chilled coolant from the first flow path during a cooling mode.

A method of defrosting a refrigeration device having a first loop with a refrigerant configured to remove heat from a coolant in a second loop, the method comprising:

• providing a first cooling element and a second cooling element in the refrigeration device adapted to cool a space, each cooling element communicating with the second loop;
• providing a heat exchanger communicating with the second loop and adapted to transfer heat from an air source to the coolant in a first mode;
• and
• providing a control system operable to route the coolant in a first flow path when the cooling element is in the first mode and operable to route the coolant in a second flow path when the cooling element is in a second mode;
• wherein the first flow path includes the heat exchanger and at least one of the first cooling element and the second cooling element, and the second flow path includes at least one of the first cooling element and the second cooling element and bypasses the heat exchanger.

An ambient air defrost system for a temperature controlled display device of a type configured for use in a supermarket having a first loop adapted to circulate a refrigerant therein and a first heat exchanger configured to transfer heat from a second loop to the first loop, the second loop adapted to circulate a coolant therein and through at least one cooling element for cooling a space within the display device, the ambient air defrost system comprising:

• a defrost line having a first end and a second end coupled to the second loop upstream of the cooling element;
• at least one flow control device configured to permit flow through the defrost line during a defrost mode and configured to prevent flow through the defrost line during an operating mode;
• a control system operable to control operation of the flow control device in the operating mode and the defrost mode;
• a second heat exchanger communicating with the defrost line, the second heat exchanger adapted to transfer heat from an ambient air source to the coolant during the defrost mode;
• so that the coolant can be warmed for defrosting the cooling element using an ambient air source that is substantially independent of a heat source from the first loop.

A system for cooling articles in a display case, comprising:

• a space within the case configured to contain the articles;
• a first cooling surface adapted to provide cooling of the articles within the space;
• a fluid supply system providing a first flow path and a second flow path for routing a fluid to the first cooling surface;
• a first heat exchanger adapted to remove heat from the fluid on the first flow path for cooling the first cooling surface in a first state;
• and
• a second heat exchanger adapted to elevate a temperature of the fluid on the second flow path for warming the first cooling surface in a second state by transferring heat from an air source to the fluid;
• and
• a flow control device configured to direct flow of the fluid through the first flow path during the first state and to direct flow of the fluid through the second flow path during the second state.

A method of installing a refrigeration system having a coolant adapted to circulate in a piping network with a flow rate to a cooling element, comprising:

• configuring the piping network to include at least a first flow path for cooling the cooling element and a second flow path for defrosting the cooling element;
• coupling the piping network to a coolant source;
• configuring a control system to transmit the coolant through the first flow path to cool the cooling element and through the second flow path to defrost the cooling element;
• providing a heat exchanger on the second flow path for receiving and warming the coolant with an ambient air source;
• and
• balancing the flow rate of the coolant to the cooling element.