Models 947, 948 and 960 Leak Detectors Operations and Service Manual
B-26
B.5.2 Dry System
B.5.2.1 Removing the Dry System Forepump
To perform this procedure:
1. Disconnect the mains power supply and make sure that all pumps are off.
WARNING
Disconnect power from the 947/948/960 before
performing any maintenance procedure that requires
physically disconnecting any part of the system.
CAUTION
Models 948/960 only:
Remove, empty, and clean the
cold trap whenever power is removed. Refer to “Liquid
Nitrogen Cold Trap (Models 948/960 only)” on
page 4-10.
WARNING
To avoid injury, use proper lifting techniques when
moving pumps. Your system may have pumps that
require two people to move them safely.
2. Remove the front panel.
3. Remove the right side panel.
4. Disconnect the power plug of the pump from the 947/948/960.
The plug is located behind the turbo and is best accessed from the right panel.
5. Remove the NW25 clamp from the left manifold.
6. Remove the centering ring and O-ring. Place them on a clean surface.
B.5.2.1.1 Removing the Isolation Valve from the Forepump
To perform this procedure:
1. Remove the VPI valve.
2. Remove the NW25 clamp from the top of the pump.
3. Disconnect the NW25 clamp at the opposite end of the valve.
