Apparatus and method for cleaning hvac cooling coils

A method of cleaning an HVAC coil unit located above a drain basin, said method comprising steps of:

• providing a supply and collection assembly having a reservoir containing liquid cleaning solution, a pump operative to output the liquid cleaning solution through a supply outlet, and a vacuum source operative to draw in used liquid cleaning solution through a collection inlet;
• providing a nozzle device in fluid communication with the supply outlet, said nozzle device having a delivery face having a substantially planar surface for juxtaposition on a surface of the HVAC coil unit, a plurality of apertures being defined in said delivery face for passage of the cleaning solution;
• providing a fluid return tool in fluid communication with the collection inlet, and positioning the fluid return tool in the drain basin;
• providing a filter assembly between the fluid return tool and the collection inlet in the fluid return path;
• and
• moving the delivery face of the nozzle device across the surface of the HVAC coil unit to deliver the cleaning solution into areas between fins thereof.