KAESER KOMPRESSOREN M170, Руководство по обслуживанию, Страница: 116 / 280

2. Close the door.
Determine and rectify the cause of coolant loss.
10.4.1.2 Checking the coolant
The coolant should be checked according to the maintenance schedule to ensure quality and opera‐
tional life.
Coolant quality can be determined by the following parameters:
■ Visual check
■ Antifreeze concentration measurement
➤ Unscrew and remove the expansion tank filler cap
1
.
Visual check
The coolant should be checked for its colour and any particles or sediments floating in it.
➤ Take a coolant sample and analyze.
The coolant is discoloured and/or has contains floating particles. Change the coolant.
Antifreeze concentration measurement
An instrument (e.g. refractometer) is used to check antifreeze concentration.
Maximum frost protection is ensured with an antifreeze concentration of 55% by volume, as frost
protection and heat transfer properties deteriorate beyond this point. Higher concentration also leads
to higher operating temperature.
CAUTION
The engine can be damaged if the antifreeze concentration is insufficient.
Corrosion
Damage to the cooling system
Engine casing fracture
➤ Check coolant.
➤ Protect the coolant against frost.
➤ Top up as necessary.
1. Use the coolant tester as instructed by the manufacturer to test the coolant.
When the concentration of antifreeze is too low: Change the coolant.
1. Screw on the filler cap.
2. Close the door.
10.4.1.3 Mixing coolant
Do not use water without coolant additive. Water alone is corrosive at engine operating temperature.
Water also offers no protection from boiling or freezing.
The coolant is a mixture of clean, fresh water and antifreeze with corrosion inhibitor.
For reasons of corrosion protection and the need to raise the boiling point, the coolant must remain
in the cooling system throughout the year.
The maximum permissible coolant life is 2 years.
10 Maintenance
10.4 Engine
104
Service Manual Screw Compressor
M170 SIGMA CONTROL MOBIL
No.: 9_9425 01 E