Abstract: A method to test a heating ventilation and air conditioning (HVAC) unit for external leaks is disclosed. The HVAC unit includes a first and a second port and is coupled to an auxiliary air movement test system using one of the first or the second ports. The other of the first or the second ports of the HVAC unit is blocked. The auxiliary air movement test system includes an air movement device, a conduit, a flow velocity sensor, and a pressure sensor. The air movement device enables airflow into the HVAC unit through the conduit. The flow velocity sensor positioned within the conduit measures air velocity. The pressure sensor is positioned in proximity to a condensate drain of the HVAC unit that measures the pressure within the HVAC unit. The method disclosed determines external leaks in the HVAC unit if the measured air velocity exceeds a predefined air velocity at a predetermined pressure.