Counterclockwise to DECREASE
minimum tank level set point.
STEP 7
When the required level is reached, or if the tank is overflowing,
SLOWLY turn the adjustment screw OUT, counterclockwise, in ¼
to ½ turn increments (See Figure 6). A small amount of water will
discharge from the vent/exhaust line of the Altitude Control, signal-
ing the port connection changes of both the Altitude Control and
accelerator. The valve will start closing as indicated by the position
indicator stem movement.
STEP 8
Closing Speed Control Adjustment: The closing speed needle
valve regulates fluid pressure into the main valve cover chamber,
controlling the valve closing speed. If the downstream pressure
fluctuates slightly above the desired setpoint, turn the adjustment
screw OUT, counterclockwise, increasing the rate of closing.
The following is dependent upon the installation/application and
may not be required on all valves: When the valve is closed, the
Altitude control screw adjustment may turned OUT, counterclock-
wise, an additional ¼ to ½ turn. This will lower the shut-off level
slightly below the tank over-flow mark, eliminating any wave action
discharge from the over-flow pipe.
4 IOM-A-ACV-960-17_660-17 2115
EDP# 1917058
© 2021 Watts
IOM-A-ACV-960-17_660-17 2115
EDP# 1917058
© 2021 Watts 5
Figure 6
Model 27 - Altitude Pilot
Figure 5
Position Indicator Stem in UP Position
Indicating Valve OPEN