6
6190760 (Rev A)
120R Basic Compressor User Guide
© 2022 JUN-AIR
We reserve the right to make any alterations which may be due to any technical improvements
Printed in the USA
f
) Check intake filter
Check the intake filter and change it if necessary .
Remove the filter and replace .
g) Check the non-return valve
Turn off the compressor on the mains switch and pull out the
plug .
Empty the receiver for compressed air by operating the safety
valve . When the receiver is empty, the reading of the pressure
gauge is 0 bar .
Dismount the non-return valve from the receiver .
Disassemble the non-return valve and remove the O-ring (1)
from the piston .
Clean the non-return valve .
Mount a new O-ring and re-assemble the non-return valve .
Re-install the non-return valve .Service
Please note that all service must be carried out by a qualified
person .
Adjustment of pressure switch
The working presure has ben preset from the factory, and it is
normally not necessary to change this .
However, if it is necessary to change the preset settings, the
instructions mentioned below should be followed carefully .
Warning
The compressor is constructed and approved for a max.
pressure as stated under Technical Specifications - do not
adjust to a higher pressure.
Higher working pressure will reduce the lifetime of the
compressor.
The compressor will stop at max . pressure (stop pressure) and
start again at min . pressure (start pressure) . The difference
between max . and min . pressure is the differens pressure .
Unscrew the lid of the pressure switch . Adjust max . pressure
adjusting the two springs marked A (clockwise: higher pressure) .
Adjust the two springs identically .
Adjust the differens pressure adjusting the spring marked B
(clockwise: higher differens pressure, start pressure maintained) .
Test of pumping time
The pumping time indicates the condition of the compressor .
1 . Check that there are no leaks in the system .
2 . Empty the air receiver of compressed air so that the
pressure gauge shows 0 bar .
3 . Close the filter regulator and check that the drain valve is
closed .
4 . Start the compressor and note the time it takes until it is
turned off again by the pressure switch . Check that the
pumping time agrees with the technical specifications for
the actual compressor system .
Please note that the pumping time in this manual is given for 0 to
max pressure . Deviations from this result in deviating results .
Important
Always test the pumping time when cold. If the compressor is
warm, the pumping time will be considerably longer.
