• Acceptable cycling rate of compressors, including duration of run times
• Current draw of individual compressors within acceptable values (max operating current)
• No abnormal vibrations and noise.
Oil level checking and top-up
In installations with good oil return and line runs up to 20 m, no additional oil is required. If installation lines exceed
20 m, additional oil may be needed. 1 or 2% of the total system refrigerant charge (in weight) can be used to
roughly define the required oil top-up quantity but in any case the oil charge has to be adjusted based on the oil
level in the compressor sight glass.
When the compressor is running under stabilised conditions the oil level must be visible in the sight glass.
The presence of foam filling in the sight glass indicates large concentration of refrigerant in the oil and / or presence
of liquid returning to the compressor.
The oil level can also be checked a few minutes after the compressor stops. When the compressor is off, the level in
the sight glass can be influenced by the presence of refrigerant in the oil. Always use original Danfoss POE oil 160SZ
from new cans.
Top-up the oil while the compressor is idle. Use the schrader connector or any other accessible connector on the
compressor suction line and a suitable pump. See News bulletin “Lubricants filling in instructions for Danfoss
Commercial Compressors”.
Dismantle and disposal
Danfoss recommends that compressors and compressor oil should be recycled by a suitable company at its
site.
© Danfoss | Climate Solutions | 2022.09
AB236986442743en-000501 | 45
Scroll compressors, CH290 and CH485 | Application