Zero adjustment of pressure sensor.
1. Set to [ZERO ADJUST] in the [CONTROL] group.
* For LC-20A / 30A, [ZERO ADJ]
2. Open the drain valve to remove pressure completely.
* For LC-40B X3/XR, the zero value of the pressure sensor of both A and B pumps is set at the same time, so open both drain valves.
3. Press [Enter].