| CPC E21B 34/10 (2013.01) [E21B 34/14 (2013.01); E21B 2200/04 (2020.05)] | 14 Claims |

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12. A method of actuating a valve, comprising:
forming an intermediate chamber between a housing and an actuation piston disposed within the housing, the actuation piston coupled to the valve;
preventing the actuation piston from actuating the valve by blocking fluid flow between the intermediate chamber and an atmospheric pressure chamber formed in the housing;
opening communication between the intermediate chamber and the atmospheric pressure chamber; and
reducing a pressure in the intermediate chamber by transferring fluid from the intermediate chamber into the atmospheric pressure chamber, thereby causing movement of the actuation piston to actuate the valve, wherein reducing the pressure in the intermediate chamber causes movement of an intermediate piston into engagement with an abutment of the actuation piston.
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