You clicked on a Latching Valve

The tank is connected to the two thruster blocks via two Latching Valves, to enable either section to be isolated during operations, or in the event of a leak developing in one of the pipe branches. Each valve can latch in the 'open' or 'closed' position. The latching valves can also allow backflow of fuel from the branches into the tank when in the 'closed' position; this is order to prevent excessive pressure buildup in the pipe sections. For a clearer view of the role of latching valves, see the Reaction Control Subsystem connectivity diagram.

 

The following commands are used to control the positions of the two latching valves:

Z201 LV1 ON-1 Open Latching Valve 1 using AOCE 1

Z202 LV2 ON-1 Open Latching Valve 2 using AOCE 1

Z203 LV1/2 OFF-1 Close Latching Valves 1 and 2 using AOCE 1

Z204 LV1 ON-2 Open Latching Valve 1 using AOCE 2

Z205 LV2 ON-2 Open Latching Valve 2 using AOCE 2

Z206 LV1/2 OFF-2 Close Latching Valves 1 and 2 using AOCE 2