MAINTENANCE
SCHEDULE:
• Inspect paddle annually. Turbulent or high
flow velocity conditions may require more
frequent inspection and/or replacement.
• Replace paddle if damaged or showing signs
of wear.
• Replace flow switch every 5 years or 100,000
cycles, whichever occurs first.
TROUBLESHOOTING
Problem:
1. Flow Switch Does Not Operate
Solution:
a.
Make sure power has been turned on to device
and flow switch.
b.
Verify that flow rate is high enough for flow switch
to activate. Measure flow rate and match with
velocities shown in flow rate chart.
c.
Check to see if paddle moves freely. Some system
piping disassembly may be required.
2. Flow Switch Operates Erratically
Solution:
a.
Flow switch may be located in an area of high
turbulence causing paddles to flutter.
b.
Adjustment screw may have been turned below
original factory setpoint. Verify that flow rate is high
enough for flow switch to activate. Measure flow
rate and match with velocities shown in flow
rate chart.
c.
Check to see if paddle moves freely. Some system
piping disassembly may be required.
3. Flow Switch Does Not Deactivate
Solution:
a.
Check to see if paddle moves freely. Some system
piping disassembly may be required.
b.
Measure flow rate and match with velocities shown
in flow rate chart. Flow switch must prove flow
before it can indicate no flow.
STEP 6 - Adjustment
COMMON
NORMALLY
OPEN
NORMALLY
CLOSED
ADJUSTMENT
SCREW
Adjustment is necessary only if required flow/no flow set-
points are
above
factory set minimum.
a.
Turn off power. Remove electric enclosure cover.
b.
Turn the adjusting screw clockwise to increase setpoint.
c.
Place cover on flow switch and turn on power.
d.
Test the operation of the flow switch after each
adjustment.
IMPORTANT: Do not attempt to lower flow switch
setpoint from original factory minimum setting.
Lowering (turning adjusting screw counterclock-
wise) the setpoint from original factory setting
may cause erratic flow switch operation.
McDonnell & Miller