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Operation
3A4802D
27
The blast spray pattern is
sputtering or irregular.
The air supply is inadequate.
Make sure the air compressor is capable of
supplying the minimum air flow requirement
for your system (see Technical Specifica-
tions, page 45). Make sure the air inlet pres-
sure gauge reads 100-150 psi (6.8–10.3 bar,
0.68–1.03 MPa). If the gauge does not read
100-150 psi, check the air compressor for
proper setup (consult your air compressor
manual, see Related Manuals, page 2).
Make sure the air inlet filters are clean and
replace if necessary.
The blast hose was not properly
cleaned out after previous use.
See Shutting Down, page 17.
The abrasive metering valve
setting is too high for the blast pres-
sure and/or abrasive type.
See Setting the Abrasive Metering Valve,
page 13.
The pot does not have a sufficient
amount of abrasive.
See Refilling the Pot with Abrasive, page
17.
There is an obstruction in the
nozzle
Remove the nozzle and inspect for block-
age, buildup, or damage. Replace if neces-
sary.
There is an obstruction inside the pot
or inside the abrasive hose between
the pot and the enclosure.
Follow Debris in Media Path on page 29, to
check for obstruction.
The fill/flush valve is open.
Close the fill/flush valve.
Too much dust occurs during
blasting.
There is not enough water in abra-
sive mixture.
The media is too fine--use a coarser media.
The blast pressure is too high.
Decrease the blast pressure and re-evaluate
the dust level.
Too much water is coming
from the nozzle in BLAST
mode.
The abrasive material is too coarse.
If possible, use at least a 40 mesh abrasive
material. Otherwise, decrease the CPM set
point until the pattern improves.
The abrasive metering valve setting
too high for blast pressure and/or
abrasive type.
See Setting the Abrasive Metering Valve,
page 13.
The fill/flush valve is open.
Close the fill/flush valve.
In WASH mode, little or no
water is flowing from the noz-
zle.
Wash down line is clogged with
media or other debris.
Remove wash down line and clear debris.
Obstruction in blast outlet manifold.
Follow Debris in Media Path on page 29, to
check for obstruction.
Problem
Cause
Solution