This article reports a study on the numerical solution of simultaneous free convection inside empty freezer enclosures with four vertical surfaces as cold isothermal and conduction in the insulation around six faces of the enclosure. The air in the enclosure comes down along the four vertical cold surfaces and rises through a smaller volume away from the vertical walls. The air temperature increases with the distance from the cold surfaces, and at the central region of the freezer, the temperature may be undesirably high, especially for freezers with lower height. Freezers with lower height have a higher average temperature in the storage space and also experiences higher heat loads. Significant temperature variation exists in the vertical direction too, and the upper part of the freezer has a relatively higher temperature. (c) 2007 Elsevier Ltd. All rights reserved.