Translation of the original operating instructions
DUO
MIX
270
43
DM270_BAoDB_en_1507 • rs
Troubleshooting
7 Troubleshooting
Fault
Possible cause(s)
Elimination
Pressure release not possible
(compressed air shut-off valve
closed)
Return hose or return ball valve
clogged
Clean return hose and return ball valve,
replace if required.
High pressure filter clogged
Clean filter element, replace if required.
The proportioning pump does
not start, despite operation of
spray gun or opened return ball
valve on mixing unit.
Compressed air shut-off valve
closed
Open the compressed air shut-off valve.
The air inlet pressure is too low Increase the air inlet pressure.
High pressure filter clogged
Clean filter element, replace if required.
Spray gun clogged
Check nozzle and filter element, replace if
required.
Return hose or return ball valve
clogged
Clean return hose and return ball valve,
replace if required.
Air motor defective
Repair air motor – if necessary call the
WIWA
customer service for assistance
The proportioning pump is run-
ning but no or too little material
is being delivered
Suction strainer clogged
Clean strainer and replace if necessary
Suction hose clogged
Clean hose and replace if necessary
Ball of bottom valve does not lift
off in the upward stroke (stuck)
Slightly knock the bottom valve from the side
(hammer). If this does not help, unscrew the
suction system and loosen the ball in the
bottom valve from underneath
Bottom valve does not close in
the downwards stroke
Unscrew the bottom valve, thoroughly clean
the ball and the seat.
The proportioning pump or the
flushing pump does not stop
when the spray gun is closed.
Packing or valve worn
Replace worn parts.
The proportioning pump is run-
ning but the required spraying
pressure is not being reached.
The air inlet pressure is too low Increase air inlet pressure on compressed air
regulator. If this does not help, check air line
for correct size and compressor output
Spraying nozzle too big
Install a smaller spraying nozzle.
Spraying nozzle worn
Replace spraying nozzle.
Air motor iced (runs to slowly)
If possible reduce the air inlet pressure.
The proportioning pump runs
irregularly (can be noticed by
differences in up and down
stroke speeds) and does not
reach the re- quired spraying
pressure.
The viscosity of the spraying
material is too high (suction
losses)
Dilute the spraying material.
Suction system leaking (fluctua-
tions in spray jet)
Check seals and fittings in the suction system
and replace if required.
Bottom valve leaking (pro-
portioning pump only stops in
upward stroke when the spray
gun is closed).
Unscrew bottom valve, clean and check ball
and valve seat, replace ball or valve seat if
required.
Piston valve leaking (propor-
tioning pump only stops in
downward stroke when the
spray gun is closed).
Clean and check ball and valve seat in the
dual piston, replace ball or valve seat if
required.
Bottom or top packing worn
Replace the packing.
