2.8 Troubleshooting
Problem
A Protective
motor
switch
interrupts
power supply
B Pressure relief does
not function
(only devices with-
out
membrane
dryer)
C Compressor
not
start
when
switched on.
D Compressor
starts
up briefly / buzzes
and then switches
off automatically
E Compressor
continuously
Cause
In case of malfunctions (e.g.
overheating;
extension cable too long or
with incorrect cross-section),
the protective motor switch is
tripped.
Period between manual switch-
off and switch-on too short
(only devices with membrane
dryer)
Solenoid valve faulty
does
Vessel pressure is higher than
switch-on pressure.
Power supply faulty.
Protective motor switch inter-
rupts power supply.
Pressure switch defective
Mains connection cable longer
than permitted or the cross
section is too small
runs
Intake filter badly contami-
nated
Air consumption of compressed
air tools is too high
Leakage at compressor
Excessive condensate in the
vessel (only devices without a
membrane dryer)
Compressed air line leaky
Condensate drainage ball valve
open
Filter elements upstream of
membrane
clogged
(only
membrane dryer)
Remedy
Switch off the compressor. Wait a
low
voltage;
short while. Actuate the protec-
tive motor switch is available.
Switch on the compressor.
Protective motor switch trips
again: switch off compressor.
Disconnect the power supply.
Contact the service partner
Increase the period between
manual switch-off and switch-on
(approximately 20 seconds).
Replace or contact service part-
ner
Relieve pressure in the vessel
until the pressure switch is acti-
vated automatically.
Have the power supply checked
by a qualified person (service
partner).
See item A.
Have
changed by a qualified person.
Check connection cable length
and
Chap. 2.4.4)
Clean or replace
Check air consumption. Contact
the service partner
Locate leak, contact service part-
ner
Drain (see Chap. 2.6.6)
Check the compressed air net-
work, seal leak
Close
Replace
dryer
heavily
Chap. 2.6.10 and 2.6.11)
devices
with
UNM Clean - OF
the
pressure
cable
cross-section
filter
elements
GB
switch
(see
(see
II/11