Magnetically-actuated manually-operated isolation valve

A valve, comprising:

• a body having a flow passage therethrough extending between an inlet and an outlet, said body having a seat surrounding an intermediate portion of said flow passageway;
• an armature mounted on said body for movement toward and away from said seat;
• a seal member carried by said armature, said seal member being adapted to be moved toward said seat and to engage said seat to close said passageway, and adapted to be moved away from said seat to open said passageway;
• a shorting member adapted to be selectively mounted on said body in one position;
• and
• a magnet mounted on one of said body and shorting member;
• said body, magnet and shorting member being so configured and arranged such when said shorting member is not mounted on said body in said one position the magnet flux will follow a first flux path through said body and armature to cause said armature to move to a first position relative to said seat, but when said shorting member is mounted on said body in said one position said magnet flux will follow a second flux path through said body and shorting member to cause said armature to move to a second position relative to said seat;
• whereby said armature will be in said first position when said shorting member is not mounted on said body in said one position, and in said second position when said shorting member is mounted on said body in said one position.