Troubleshooting Possible Problems In Operation - DeVilbiss SRI PRO series Technical Bulletin

Page 14 SB-2-855-B

TROUBLESHOOTING POSSIBLE PROBLEMS IN OPERATION

CONDITION
Heavy top or
bottom pattern
Heavy right or
left side pattern
Remedies for the top-heavy, bottom-heavy, right-heavy, and left-heavy patterns:
1 . Determine if the obstruction is on the air cap or the fluid nozzle . Do this by making a test spray pattern . Then,
rotate the cap one-half turn and spray another pattern . If the defect is inverted, obstruction is on the air cap . Clean
the air cap as previously instructed . Also check for dried paint just inside the cap center hole opening; remove by
washing with solvent .
2 . If the defect is not inverted, it is on the fluid nozzle . Clean nozzle . If problem persists, renew nozzle .
Heavy centre
pattern.
Split spray
pattern
Jerky or
fluttering spray
Paint bubbles in cup
CAUSE
Horn holes plugged .
Obstruction on top or bottom of fluid
nozzle .
Cap and/or nozzle seat dirty .
Left or right side horn holes plugged .
Dirt on left or right side of fluid
nozzle .
Spreader adjustment valve set too
low .
Atomizing pressure too low .
Material too thick .
Air pressure too high .
Fluid adjusting knob turned in too far .
Spreader adjusting valve set too
high .
Loose or damaged fluid nozzle/seat
Loose or broken cup fluid nipple
Material level too low
Container tipped too far
Obstruction in fluid passage
Loose fluid needle packing nut
Damaged fluid needle packing
Fluid nozzle not tight .
CORRECTION
Clean . Ream with non-metallic point .
Clean .
Clean .
Clean . Ream with non-metallic point .
Clean .
Turn out counter clockwise to
achieve correct pattern .
Increase pressure .
Thin to correct consistency .
Reduce at regulator or gun handle .
Turn out counter clockwise to
achieve correct pattern .
Turn in clockwise to achieve correct
pattern .
Tighten or replace
Tighten or replace cup
Refill
Hold more upright
Back flush with solvent
Tighten
Replace
Fluid nozzle not tight . Tighten to
9-10 Nm (80-90 in-lbs) .