Provided is a first vapor phase valve 10a including an housing 11, a flow passage 12 provided in the housing 11, a main valve 15 configured to block or open the flow passage 12, and an excess flow valve 17 configured to block the flow passage 12 when vapor phase DME flows through the flow passage 12. Since the first vapor phase valve 10a is configured to include: a pressure chamber 40 communicating with a pressure opening portion 41 of the housing 11; and a fixed shaft 19 connected to the excess flow valve 17 and configured to maintain the excess flow valve 17 in an open state by using pressure of liquid phase DME flowing into the pressure chamber 40 from the pressure opening portion 41, the excess flow valve which prevents fluid from flowing out at a specified flow rate or more can be forcedly opened.
