the compartment floor. Water from the water (heater
tween the outlet and inlet pressure indicators is caused
pressure relief) valve will flow out of the floor drain
by obstruction to the waterflow due to the accumulation
manifold. The floor drain manifold may be lifted slightly,
of foreign particles in the micron filter.
if required, to allow the water on the compartment floor to
(3) Flow indicator. Any flow of water within the
drain to the outside of the darkroom.
water system will cause the white needle within the flow
f. Water System Indicators. The functions of the
indicator to spin, indicating both waterflow and direction
indicators used to monitor the operation of the water
(4) Pressure vacuum indicator. When valve S8
system are described below.
(1) Inlet pressure indicator. The inlet pressure
is closed, the pressure vacuum indicator will indicate the
amount of vacuum at the top of the water tank in psi, as
indicator measures the pressure of the water as it leaves
water is removed from the water tank.
the pressure regulator. If the pressure regulator is
(5) Level indicator. By measuring the difference
functioning normally, the maximum pressure indicated
between the air at the top of the water tank and the water
will be 40 psi.
(2) Outlet pressure indicator.
at the bottom, the level indicator monitors the level of
water in the water tank.
pressure indicator measures the actual water pressure in
A difference in pressure be