23
7 Troubleshooting
Error
Possible cause
Remedy
During operation, air
bubbles appear in the
suction line above the
dispense head.
Lowermost o-ring on the
dispense head, which
separates the liquid channel
from the vent channel, is
damaged.
Replace o-ring.
For chemicals with high
vapor pressure (e.g. NH4OH
28 %), an increased pressure
drop in the suction line can
lead to the formation of gas
bubbles or the liquid column
can break off.
Shorten the suction line,
Use of a dispense head with
manual shut-off valve.
Container contracts
during operation and/
or when the system is
stopped.
Vent channel of the dispense
head closed or not free.
Clean the dispense head,
e.g. in an ultrasonic cleaner.
Ventilation of the container
is not sufficient to achieve
complete pressure
equalization.
Reduce the dispensing flow
rate of the operating medium.
Dispense head can only
be screwed into the dip
tube at an angle or not
completely.
Thread on dip tube damaged.
Contact chemical filler /
manufacturer / supplier or
technical customer service of
AS Strömungstechnik.
Thread on the dispense head
damaged.
Contact AS
Strömungstechnik technical
customer service, send in the
dispense head for repair, see
Section 9.3.
Operating medium
escapes from dispense
head inlet (liquid
channel).
Contaminations/deposits in
the valve.
Clean/rinse the dispense
head.
Valve body or seal damaged.
Contact AS
Strömungstechnik technical
customer service, send in the
dispense head for repair, see
Section 9.3.
