01/10
Model 2000SM
Page 6 of 9
SENSOR TROUBLESHOOTING GUIDE
NOTE:
Sensor requires no calibration. If unit is powered, unit should activate when an
object is placed beneath the nozzle and in front of the sensor. Note that when the
sensor is triggered, the LED lights in the nozzle activate immediately, whereas the
solenoid valve opens after a slight delay.
Certain bottles or containers may not be readily detected by the sensor, either because
of their material or their shape. If this is the case, it may be useful to hold a different
region of the container in front of the sensor, or simply make sure that one’s hand is in
front of the sensor.
STEP 1:
A click or hum indicates when the solenoid valve is activated. If valve clicks or hums,
but no water dispenses, make sure pressure regulator and screwdriver stop are
sufficiently open. If valve clicks or hums, but there is still little or no flow, check
solenoid valve, valve y-strainer, and plumbing lines for obstruction. If no obstructions
are located, replace valve.
If valve does not click or hum when hand is placed in front of sensor, go on to next
step.
DO NOT ATTEMPT TO DISASSEMBLE SENSOR; DAMAGE MAY RESULT.
STEP 2:
With power on and door closed, look closely at LEDs in nozzle assembly to confirm
that the LEDs are flashing at reduced brightness. This indicates that the unit is
receiving power.
STEP 3:
If LEDs are not flashing, check the fuse and replace if necessary.
STEP 4:
If fuse is good and LEDs are not flashing, use a voltmeter to check for 120 VAC at
the “Open” terminal of the interlock switch with the door opened. This verifies power
into the unit. Disconnect power and verify continuity between the two terminals of
the interlock switch while switch is depressed. If there is no continuity, the interlock
switch is not closing the power circuit and must be replaced.
STEP 5:
If
the above steps do not produce results, check for 120 VAC across the wiring
terminals on the solenoid valve while the sensor is triggered. Replace valve/regulator
assembly if a 120 VAC reading is obtained and water does not dispense.
STEP 6:
If the above tests do not yield any conclusive results, contact Haws Technical
Support. Be certain not to attempt to troubleshoot or touch the main circuit board.
For more information about Haws products, see our website: www.hawsco.com
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®
Corporation – All Rights Reserved
HAWS
®
and other trademarks used
in these materials are the exclusive property of Haws Corporation.
