User guide

Troubleshooting 39
6 Troubleshooting
Overview
If you have difficulty operating your dispensing system, use this section to identify a possible solution to the
problem. If you have difficulties not listed in this section, or the suggested solution does not correct the
problem, contact Nordson ASYMTEK Technical Support.
Safety First
It is essential that you follow all safety warnings and consider all safety warning labels when performing the
troubleshooting procedures. Refer to the Safety section for specific information.
CAUTION! Troubleshooting should be performed by trained personnel only.
Record Keeping
The type of procedure performed should be recorded in maintenance records. Dates, part numbers/serial
numbers of replaced parts, names of technicians, and other pertinent data should be recorded.
Troubleshooting the DispenseJet
To quickly identify problems, look for obvious signs such as burnt, missing, damaged, or loose parts, as well
as fluid obstructions and leakages. If a problem recurs, there may be other root causes. Table 6-1 facilitates
troubleshooting based on symptoms.
Table 6-1 Troubleshooting
Symptom Possible Cause Recovery
Nozzle is capping over (tip is
covered with fluid.
Heat setting is too low.
Raise the temperature. See the Fluidmove
User Guide or Online Help.
Incorrect Micro-Adjustment or
Preload settings.
Adjust the Micro-Adjustment and/or Preload
Screw.
Inadequate purge routine.
Increase purge frequency. Refer to “Purging
the DispenseJet” in the Operation section.
Fluid continuously oozing from the
nozzle.
Incorrect offset of the air piston to jet body.
Refer to “Reassembly of the DispenseJet” in
the Maintenance and Service section.
Dispenser still dispenses even
when Micro-Adjustment is set
to 0.0 mm.
Micro-Adjustment outer collar
bottomed out on the Locking ring.
Adjust micro-adjustment collar.
Micro-Adjustment does not touch
the top of the needle even when it is
bottomed out (Preload is set to <
3.5 turns).
Preload must be set to 3.5 to 4.5 turns.
Tear-shaped or poor-quality
dots (in various directions.
Heat setting is too low.
Raise the temperature. See the Fluidmove
User Guide or Online Help.
Incorrect micro-adjustment or
preload settings; preload screw may
not be tight enough.
Adjust the micro-adjustment and/or preload
screw.
Nozzle is dirty. Clean the nozzle with solvent.