Patent ID: 6962318

Claim:
A combination for application onto a pressurized fluid line having upstream and downstream ends, comprising: a) a shutoff valve having an inlet for connection to the upstream end of the pressurized fluid line, an outlet for connection to the downstream end of the pressurized fluid line, and a springless actuator for driving a plug between open and closed positions of a main flow path connecting the upstream and downstream ends through the shutoff valve, and an upper chamber adjacent the springless actuator; b) a normally closed two-position solenoid valve controlling flow between the upper chamber and an inlet bypass channel connected to the inlet of the shutoff valve; and c) a fluid reset switch controlling flow between the upper chamber and a outlet bypass channel connected to the outlet of the shutoff valve; in which a region of reduced pressure is located downstream of the springless actuator but upstream of the downstream end of the pressurized fluid line, the region of reduced pressure being connected to the outlet bypass channel side of the fluid reset switch.