US Patent 11486663 Apparatus and method for cleaning HVAC cooling coils

An apparatus for cleaning HVAC cooling coils comprises a supply and collection assembly having a housing defining an interior space for containing a quantity of cleaning solution. A pump has a pump inlet positioned to be in fluid communication with the cleaning solution and is operative to deliver the cleaning solution to a supply outlet of the supply and collection assembly. A vacuum source has a vacuum inlet positioned to be in fluid communication with an ullage space above the quantity of cleaning solution such that the vacuum source creates negative pressure in the ullage space during operation. A collection inlet is in fluid communication with the ullage space such that the cleaning solution is returned to the interior space through the collection inlet during operation of the vacuum source. A nozzle device is in fluid communication with the supply outlet via outlet piping so as to deliver the cleaning solution to a surface of an HVAC coil unit. A fluid return tool is in fluid communication with the collection inlet via return piping so as to collect used cleaning solution from the HVAC coil unit.