(9) Check the circulation system. Separate pumps circulate the developer
and the fix in the solution tanks. The pumps operate constantly when the power switch
is ON. A solenoid valve turns the water ON and OFF. See figure 1-14. The level
detector circuit automatically fills the developer tank and keeps it filled using detector
probes at the top of the developer tank. A replenisher pump activates and adds
replenisher to top off the tank. Expended fix and developer solutions overflow into the
drain ports on the right side of the tanks and into the drain manifold. If the fix drain port
becomes plugged, the solution flows into a safety drain port. The wash tank has an
overflow weir at the rear of the tank for skimming action. When you turn off the
machine, the drain solenoid opens and the wash tank drains directly into the drain
manifold. Poor solution circulation can contribute to a variety of problems associated
with temperature control and film artifacts. Lack of proper circulation can be caused by
the following conditions: stagnating chemistry, resulting in deposits in tanks and lines;
lack of regular draining and flushing of tanks and lines; application of power when tanks
are empty causing pumps to overheat; kinks or restrictions in the lines.
Figure 1-14. Wash fill solenoid valve location.
(a) Check for clogged circulation lines and flush as necessary. Since
the pumps and lines are below the tanks, they must be flushed whenever you change
the chemistry. To do this, you turn OFF the power switch and remove the top cover and
side panels. You drain the developer and fix tanks by opening the valves on the drain
lines from the pump. You fill the developer and fix tanks with water up to the standpipe
level. Turn ON the power switch. Run the processor for a few minutes, then turn OFF
the power switch. Drain the tanks. Make sure all connections are tight before adding
(b) Check for evidence of leakage. Refer to paragraph 1-4a(7)(f).