DirectFlo DF1400
Chapter 5: Trouble-Shooting and Repair
Comco Inc.
5-6
Issue Date: January 2009
Moisture
If the cutting action of your DirectFlo appears to be degraded but air is flowing freely
from the nozzle, the problem is usually caused by moisture in the abrasive powder.
How to Check for Moisture in the Powder
With the Power OFF and the unit depressurized, carefully remove the tank cover so as
not to disturb the c
ontents. Is the powder “channeling”? In other words, are there
obvious holes or cracks through an apparently solid mass or clumps of powder? If so,
you have a moisture problem. See Chapter 4, “Moisture”, on how to prevent moisture
from contaminating your powder.
Clogging
Tank Orifice
Moisture or particulate matter contamination in the abrasive powder can cause clogging
problems in your DirectFlo. The most likely place for clogging to occur is in the tank
orifice. Provided the orifice is sized properly for the type of abrasive being used (see
Chapter 3, “Orifice Selection”), the powder should always flow freely from the tank.
Since the tank orifice is the only way for the powder to get from the tank to the mixing
chamber, a clog here restricts or prevents powder flow. If air is flowing freely when the
footswitch is depressed but there seems to be no abrasive in the air stream, first check
for moisture contamination as described in the previous chapter. Then remove the tank
orifice (see Chapter 3,
“Changing the Tank Orifice”), check it for clogging and clean if
necessary. Try to determine if clogging is due to either moisture or particulate
contamination.
Nozzle
If the unit is pressurizing and you can see the pinch opening when the footswitch is
depressed, but no air is flowing from the nozzle, the nozzle is probably plugged. This is
a common problem only when using small nozzles with the nozzle adapter. The most
likely cause of nozzle clogging is an oversized tank orifice. Too much powder in the air
stream can overload the nozzle and cause clogging (see Chapter 3, “Orifice/Nozzle
selection”).
Remove the nozzle. Tap it on the workbench, back end down, to release the clog.
Check it by holding the tip to a light. A point of light should be visible through the tip.
Discard the nozzle if it remains plugged.
If plugging recurs, either the tank is releasing too much powder or the nozzle is too small
for the powder. Refer to Chapter 3 for direction.
