JUN-AIR 4000 series [no cabinet] - Handbuch (Seite 12)

12
An hour meter is installed on all "BD" and "PD" models.
Observe after 1 month how many hours the compressor has
performed in order to obtain an impression of the maintenance
intervals - which are every 2000 working hours. However, at
least once every year.
Replace the air intake filters after each 2000 working hours
1. Switch off current.
. Lift off the upper part of the cabinet (is locked with screws).
Be careful not to unplug the cable for the fan (this only
applies to model „P“) (fig. 4).
3. Pull out the filters by means of inserting a screwdriver below
the rubber part. The new filters can then be pressed into
place (fig. 5).
Compressors with adsorption dryer:
1. Test that the automatic dryer/filter works satisfactorily
by opening the manual control drain cock, which has an
internal tube leading to the bottom of the air receiver. If
water comes out, the dryer needs to be serviced. (See
"Adsorption Dryer Manual").
2. In order to avoid pressure loss due to saturated filter
element, the pre and after filters are equipped with a pop-
up indicator. When the filter element needs replacement,
the indicator turns red instead of green. Under normal
conditions the filter element must be replaced after
approx. 4000 working hours. If the environment is very
contaminated, intervals for changing filter element may be
000 working hours. See "Adsorption Dryer Manual" for
further information.
3. After 000 to 4000 working hours dependent on the working
conditions or when desiccant in inspection glass changes
color, the desiccant in the dryer system must be replaced,
see "Adsorption Dryer Manual".
Check the pumping time
The pumping time indicates the condition of the compressor
provided that there
are no leaks in the system where the compressed air may leak.
Test the compressor as follows:
1. Empty the air receiver of compressed air (the pressure
gauge shows 0 bar).
. Close the outlet on the air receiver and check that the drain
cock is closed.
3. Start the compressor and note how long it takes until it
switches off.
Make sure that the pressure in the air receiver is 8 bar/10
psi as deviations may indicate the wrong results (see
technical details).
Important!
Always test the compressor when cold as the time
indicated refers to the pumping time of a cold
compressor. The pumping time of a warm compressor
is much longer and consequently, the result would be
misleading.
Automatic reset protector
The unit is equipped with a thermal protector that cuts of the
compressor motor if the temperature is too high or the amps
drawn by the unit exceeds a certain limit. The protector has a
automatic reset which means that when the temperature of the
motor drops under the cut-in value of the protector the motor
automatically will start operating.
Fault finding and repair
Important!
Switch off and isolate from electrical supply before
removing any parts from the compressor.
Empty air receiver of air before dismantling any parts
of compressor unit’s pressure system.
1. Compressor does not start (no sound):
a) No power from mains. Check fuses and plug.
b) Breakage or loose joints in electrical connections.
c) Pressure in the air receiver is too high for activation
of the pressure switch. The pressure switch makes
circuit only when pressure has dropped to preset start
pressure. Empty receiver.
d) Capacitor defective.
2. Compressor does not start, makes a buzzing sound
followed by clicking noise (cannot start against high
pressure):
a) Leaky non-return valve. Remove the flexible pressure
pipe and clean to find out whether air leaks from the
valve. If so, clean or replace.
3. Compressor works, but pressure does not increase in
tank (or increases too slowly):
a) Intake filter clogged. Replace.
b) Leaks in fittings, tubes or pneumatic equipment. Check
with soapy water. Pressure drop is not to exceed 1 bar
per hour.
c) Failure in non-return valve which is creating a flow
restriction.
d) Check the piston gaskets. Replace, if necessary.
e) Desiccant has been contaminated and/or filter elements
have been clogged (this only applies to model „D“).
Replace. See "Adsorption Dryer Manual".
4. Loud noise from compressor:
a) Dirt or failure in non-return valve. Clean or replace.
b) Defective fan (this only applies to model „P“).
5. Compressor gets very hot:
a) Leaks. See point 3b.
b) Intake filter clogged. See point 3a.
c) Too high ambient temperature. Do not enclose unit in a
cupboard unless adequately ventilated. The compressor
should be placed in coolest possible place.
d) The cooling fan at the top of the cabinet does not run
(this only applies to model „P“). Check pipes and fuses.
e) Overloaded. Ensure compressor is correct model for
work load.
6. Compressor starts when no air is being tapped:
a) Leaks. See point 3b.
7. Compressor starts and stops more frequently than
usually:
a) Large amount of condensate in air receiver (on units
without dryer). On units with dryer condensate may be
found if dryer is defective (this only applies to model
„D“).
b) Leaks. See point 3b.
8. Compressor does not switch on against pressure or
does not switch off at max. pressure:
a) Defective pressure switch. Replace.
Operating manual
GB