Development of Surface Coating for Evaporators

The purpose of this document is to present the study devoted to odor level decrease in the frame of the development of coating for evaporators.

Odor evaluation of evaporators at the different stages of climatisation running shows higher level at the AC OFF stage, which potential cause is localized on the surface coating of the evaporator. Moreover, regulation restricts strongly hexavalent chromium use that enters in composition of chromate/phosphate chromate conversion chemicals. For these reasons, a development of surface coating for evaporator has been undertaken to reduce the mentioned odor problem and to meet the environment rules dealing with hexavalent chromium removal.

A relation is observed between AC OFF stage odor evaluations made on air conditioning system equipped with evaporators treated with current hydrophilic coatings, new developed hydrophilic coating and hydrophobic polyurethane varnish and SEM analysis results obtained on the same surface coatings before and after ageing.