Figure 27: Heavy do not lift manually
HEAVY
do not lift
manually
Figure 28: Correct handling
Compressor holding charge
Each compressor is shipped with a nominal dry nitrogen holding charge between 0.3 and 0.7 bar and is sealed with
elastomer plugs.
Before the suction and discharge plugs are removed, the nitrogen holding charge must be released via the suction
schrader valve to avoid an oil mist blowout. Remove the suction plug first and the discharge plug afterwards. The
plugs shall be removed only just before connecting the compressor to the installation in order to avoid moisture
from entering the compressor. When the plugs are removed, it is essential to keep the compressor in an upright
position so as to avoid oil spillage.
System cleanliness
The refrigerant compression system, regardless of the type of compressor used, will only provide high efficiency and
good reliability, along with a long operating life, if the system contains solely the refrigerant and oil it was designed
for. Any other substances within the system will not improve performance and, in most cases, will be highly
detrimental to system operations.
The presence of non-condensable substances and system contaminants such as metal shavings, solder and flux,
have a negative impact on compressor service life. Many of these contaminants are small enough to pass through a
mesh screen and can cause considerable damage within a bearing assembly. The use of highly hygroscopic polyol
ester oil in R410A compressors requires that the oil be exposed to the atmosphere as little as possible. System
contamination is one of main factors affecting equipment reliability and compressor service life. It is important
therefore to take system cleanliness into account when assembling a refrigeration system.
During the manufacturing process, circuit contamination may be caused by:
• Brazing and welding oxides,
• Filings and particles from the removal of burrs in pipe-work,
• Brazing flux,
• Moisture and air.
Consequently, when building equipment and assemblies, the precautions listed in the following paragraphs must
be taken.
© Danfoss | Climate Solutions | 2022.09
AB236986442743en-000501 | 41
Scroll compressors, CH290 and CH485 | Application