Current gaskets fixed in domestic refrigerators door, also called gaskets, are responsible for the correct closing of the compartments. However, this sealing is not perfect and inevitable hot and humid air flow constantly penetrates the refrigerated compartments. This unwanted air infiltration leads to an increase of the thermal load of the refrigerator and frost formation on the evaporator. Besides contributing to the rise in energy consumption and loss performance, frost can block the evaporator, build up in the inner walls of the refrigerator and generate excessive amounts of meltwater, culminating in spending on technical assistance. Such effects become more apparent when there is a deviation production that prevents proper closing of refrigerator doors, resulting in the most significant air leakage rates.

In order to understand and measure air leakage in refrigerated compartments, Polo uses the technique of tracer gas: a gas is inserted measurable concentration in the refrigerator and evenly distributed throughout its internal volume; then varying the concentration of gas is measured over time. To identify and quantify the presence of tracer gas in the air is used, a photoacoustic infrared spectroscopy equipment. The tests show that the developed methodology is able to identify quickly and reliably if the refrigerator is with a proper seal or if there is a production shift, however small. The method is also able to identify and quantify improvements applied to the door seal as gasket design improvements or the support flanges.