At a site survey today we looked at the AAAON RN-050-3 50 ton RTU. There were two larger Condenser coils placed at an angle, covered from sunlight and heavy rain damage. The coils had not been coated and were very worn with severe corrosion. Other RTU's the same age as the RN-050-3 had been coated but less protected, and stood in much better shape. While natural erosion is expected, the coils did not last as long as they should have. The units were located next to an airport and directly under the path of the jet planes. The burned jet fuel in the air could be a reason for the rapid decay on the un-coated AAON condenser coils. This is an example of the difference between coated condenser coils and condenser coils that are not coated. The coating holds up very well to not only the sun and weather but potentially to destructive chemicals from various situations. Nationwide Coils offers a full service solution for all Custom and OEM HVAC Coils.