10.9.3.2 Checking the oil indicator
The fresh air filter is fitted with an oil indicator. When the indicator is blue, the filtration function can
no longer be ensured and the filter must not be used. Both filter elements and the indicator must be
changed (regardless of the maintenance schedule).
The oil indicator must be checked at least once daily.
The oil indicator does not give information on the filter element changing interval.
1. Check the oil indicator.
Indicator is blue: Replace both filter el oil level indicator.
2. Close the door.
10.9.3.3 Changing consumable parts
The fresh air filter contains two different elements which must be changed as a pair. Note their po‐
sitioning!
Do not touch the new filter elements with bare fingers, as this will impair their function!
Material Spare parts
Filter wrench
Wrench
Cleaning cloth
Clean fabric gloves
Precondition Machine is cooled down.
The «battery isolating switch» is off.
Ensuring the fresh air filter is de-pressurised:
➤ Open the fresh air filter drain tap to release any remaining pressure.
Changing the lower filter element (high performance element):
1. Unscrew the lower housing anti-clockwise.
2. Draw the filter element down and out.
3. Clean the lower housing and sealing surface with a lint-free cloth.
4. Check the housing gasket.
Housing gasket is damaged: replace gasket.
5. Insert a new lower filter element.
Wear gloves!
6. Screw on the lower housing clockwise.
Changing the upper filter element (adsorption insert):
1. Unscrew the upper housing anti-clockwise.
2. Draw the filter element up and out.
10 Maintenance
10.9 Options
No.: 9_9425 01 E
Service Manual Screw Compressor
M170 SIGMA CONTROL MOBIL
151
