An apparatus and method for determining whether two operands are less than two are disclosed. The cartons and the tray are each formed from blanks of sheet material. A coil is wound around the outer face of the support so as to contain a center axis of the heating roller inside the tubular part. When the refrigerant pressure reaches another pre-set level between the aforementioned maximum and minimum levels, in the absence of any vehicle waste energy, the clutch is again deactivated and the compressor stops. The invention also includes an apparatus made according to any combination of the above method steps andor the structure of the apparatus which is fabricated from any combination of those method steps.