A heat exchanger cleaner apparatus for spraying a cleaning composition into an interior of an air handler of an air conditioning system includes a spray outlet assembly, a pump device, and a controller. The spray outlet assembly is configured to be inserted into the interior of the air handler to be directly exposed to an outer surface of a heat exchanger of the air handler. The pump device is configured to pump an amount of the cleaning composition through the spray outlet assembly such that the spray outlet assembly sprays the amount of the cleaning composition as a fluid stream. The controller is configured to operate the pump device to cause the amount of the cleaning composition to be supplied through the spray outlet assembly without manual intervention.