Development Unit - GE PhastSystem User Manual

7. Maintenance and trouble shooting
7.2 Development
unit
76
Fig. 38. Exploded view of the contact block
The maintenance required by the operator concerns the gasket in the
lid, the gasket in the 10-port valve, and the tubing between the 10-port
valve and the chamber. The gasket in the lid should be replaced when
visibly damaged, when filling and emptying takes longer than usual or
when filling and emptying does not function properly (the chamber
must be air-tight for filling and emptying). The other two items should
be replaced if they start to leak.
Replacing the lid gasket
Just pull the gasket off. Be sure to turn the recess in the new gasket
outwards.
Replacing the 10-port valve gasket
Opening the valve
1. Start a development run (any method) but press "DEV pause/
continue" as soon as EMPTYING P0 appears on the display.
When the 10-port valve is in position P0, the channel (groove)
in the channel plate is always pointing to 12 o'clock-
2. Disconnect the development unit mains power cable.
3. Raise the valve end of the unit about 300. (Do not stand the
unit on end or residual liquid may enter delicate parts in the
unit.)
4. Unscrew the pressure plate, taking a few turns at a time on each
screw.
5. Remove the distributor and distributing plate, see figure.
Closing the valve
6. Without touching the surface of the distributing plate, place
gasket against the smooth side, notch in gasket against notch in
distributing plate.
7. Place the two parts into distributor.
8. Reassemble valve. Remember channel (groove) in channel plate
should be pointing to 12 o'clock. (The valve will not connect
ports as programmed if the channel plate is turned by 180°.)
9. Make sure the u-shaped metal piece is sitting under the valve and
that the hole for the screw is to the right. Insert the screws in the