Graco EcoQuip 2 EQs Instructions Manual page 35

Problem
The blast spray
pattern is sputtering or
irregular.
Too much dust occurs
during blasting.
Too much water is
coming from the
nozzle in BLAST
mode.
3A7467C
Cause
The air supply is
inadequate.
The blast hose was not
properly cleaned out
after previous use.
The abrasive metering
valve setting is too high
for the blast pressure
and/or abrasive type.
The pot does not have
a sufficient amount of
abrasive.
There is an obstruction
in the nozzle.
There is an obstruction
inside the pot or inside
the abrasive hose
between the pot and
the enclosure.
There is not enough
water in abrasive
mixture.
The blast pressure is
too high.
The abrasive is too fine
for the application.
The water dose valve
(S) is open too far.
The abrasive material
is too coarse.
The abrasive metering
valve setting is too high
for blast pressure
and/or abrasive type.
Make sure the air compressor is capable of supplying the
minimum air flow requirement for your system. See Technical
Specifications, page 66. Make sure the air inlet pressure gauge
reads 100-175 psi (6.8-12 bar, 0.68-1.2 MPa). If the gauge does
not read 100-175 psi check the air compressor for proper setup.
Make sure the air inlet filters are clean and replace if necessary.
See Shutdown, page 26.
See Set the Abrasive Metering Value, page 22.
Refill the pot with abrasive. See Refill Pot with Media, page 21.
Remove the nozzle and inspect for blockage, buildup, or damage.
Replace the nozzle if necessary.
Perform Drain the Pot, page 27, followed by Installation, page
12. With the abrasive hose disconnected, inspect the interior of the
pinch hose for obstructions or debris and replace if necessary. See
Replace the Pinch Hose, page 38. Remove the tri-clamp from the
bottom of pot. Inspect the bottom of the pot and abrasive hose for
obstructions or debris.
See Use the Water Dose Meter, page 29.
Decrease the blast pressure and re-evaluate the dust levels.
Try a coarser or harder abrasive if possible.
Close the water dose valve (S).
If possible, use at least 20 mesh abrasive material. Otherwise,
decrease the CPM setpoint until the pattern improves.
See Set the Abrasive Metering Value, page 22.
Troubleshooting
Solution
35