A refrigeration unit, comprising: a serpentine evaporator tube having a plurality of elongated portions and a plurality of U-shaped bends that connect the elongated portions; a heater tube in a spaced relationship with the serpentine evaporator tube and comprising: a bottom portion that extends generally parallel to at least one of the plurality of elongated portions; and a side portion that extends upward from the bottom portion generally perpendicular to the at least one elongated portion; a bracket configured to maintain the heater tube in a spaced relationship with the serpentine evaporator tube; and a wire that couples the at least one elongated portion of the serpentine evaporator tube to the bottom portion of the heater tube, characterized in that the wire comprises: a first evaporator tube receiving section that wraps about a portion of a circumference of the at least one elongated portion of the serpentine evaporator tube; a first heater tube receiving section that wraps about a portion of a circumference of the bottom portion of the heater tube; and a first spacer section that extends between the first evaporator tube receiving section and the first heater tube receiving section and is configured to inhibit movement of the first evaporator tube receiving section relative to the first heater tube receiving section, wherein the first evaporator tube receiving section contacts the at least one elongated portion of the serpentine evaporator tube and the first heater tube receiving section contacts the bottom portion of the heater tube, such that movement of the bottom portion of the heater tube toward and away from the at least one elongated portion of the serpentine evaporator tube is inhibited. a serpentine evaporator tube having a plurality of elongated portions and a plurality of U-shaped bends that connect the elongated portions; a heater tube in a spaced relationship with the serpentine evaporator tube and comprising: a bottom portion that extends generally parallel to at least one of the plurality of elongated portions; and a side portion that extends upward from the bottom portion generally perpendicular to the at least one elongated portion; a bottom portion that extends generally parallel to at least one of the plurality of elongated portions; and a side portion that extends upward from the bottom portion generally perpendicular to the at least one elongated portion; a bracket configured to maintain the heater tube in a spaced relationship with the serpentine evaporator tube; and a wire that couples the at least one elongated portion of the serpentine evaporator tube to the bottom portion of the heater tube, characterized in that the wire comprises: a first evaporator tube receiving section that wraps about a portion of a circumference of the at least one elongated portion of the serpentine evaporator tube; a first heater tube receiving section that wraps about a portion of a circumference of the bottom portion of the heater tube; and a first spacer section that extends between the first evaporator tube receiving section and the first heater tube receiving section and is configured to inhibit movement of the first evaporator tube receiving section relative to the first heater tube receiving section, wherein the first evaporator tube receiving section contacts the at least one elongated portion of the serpentine evaporator tube and the first heater tube receiving section contacts the bottom portion of the heater tube, such that movement of the bottom portion of the heater tube toward and away from the at least one elongated portion of the serpentine evaporator tube is inhibited. a first evaporator tube receiving section that wraps about a portion of a circumference of the at least one elongated portion of the serpentine evaporator tube; a first heater tube receiving section that wraps about a portion of a circumference of the bottom portion of the heater tube; and a first spacer section that extends between the first evaporator tube receiving section and the first heater tube receiving section and is configured to inhibit movement of the first evaporator tube receiving section relative to the first heater tube receiving section, wherein the first evaporator tube receiving section contacts the at least one elongated portion of the serpentine evaporator tube and the first heater tube receiving section contacts the bottom portion of the heater tube, such that movement of the bottom portion of the heater tube toward and away from the at least one elongated portion of the serpentine evaporator tube is inhibited.