To confirm operation of a flow control part such as a mass flow controller (MFC) controlling the flow of the liquid source without separating the flow control part from a liquid source feed passage in a film processing device using vaporized liquid source.

The operation of an MFC is confirmed by bypassing a part of a washing fluid feed passage for washing a liquid source feed passage, setting a flowmeter for calibration in the bypass passage, and feeding washing fluid to the flowmeter and the MFC. The flowmeter does not scale out even though the flow rate of liquid source at film processing time is small, for instance approx. 1/10 of the flow rate of the washing liquid at washing time by preventing the washing liquid to flow in the bypass passage at washing time. As another method, a relationship between a signal corresponding to an established flow rate of the MFC and a signal corresponding to the opening of a valve of the MFC is stored in advance and the comparison of this data with the data at calibration time may fulfill the object.