Manual Isolation Valve

isolation valve
(Isolation Valves) Valves used for the transfer and isolation of refrigerant charge in the cooler or condenser, allowing refrigerant to be stored inside a chiller during servicing.
(Isolation Valves) A valve that allows the fluid to be turned off at specific point in a system.
(Isolation valves) means mechanical valves located at pre-designated intervals on gas pipelines to shut the flow of gas in a pipeline to minimize an accidental release in to the environment in the event of an emergency or to facilitate the controlled release of gas in connection with testing,

manual
of or relating to the hands; "manual dexterity"
Of or done with the hands
(of a machine or device) Worked by hand, not automatically or electronically
Using or working with the hands
a small handbook
manual of arms: (military) a prescribed drill in handling a rifle