Abstract: A tank (A) stores pre-filtered anti-freeze liquid received from a pre-filter (B) for removing hydrocarbons carried within a drain pan (C) positioned beneath a radiator in an automotive vehicle. The pre-filtered anti-freeze liquid is introduced into a cartridge filter having a closure provided by a removable plug (D) for introducing diatomaceous earth into one of a serially arranged set of filters.

Abstract: A switch-controlled, ballasted, low-frequency, ultraviolet device mounted inline in an air-return system of an air-conditioning unit to resupply return air. The air-return system has an upstream filter and downstream cooling coil, drain pan and blower fan. The ultraviolet device is disposed inline between the filter and cooling coil, and in closest proximity to the cooling coil to maximize its effectiveness. Ultraviolet emissions, directed at the cooling coil and drain pan, destroy cooling-coil-and-drain-pan bacterial accumulations, growth of mold spores or slime, dust mites, airborne diseases, pollens and pollutants, and purify such return air.