Daikin WCT Series Operating & Maintenance Manual page 65

4. Pump a few strokes of the oil to fill the connection line with oil to purge air just before tightening
the connection at the charging valve.
5. Open the sump charging valve and bring the oil level to be visible on the sight glass.
6. Close the charging valve while the oil pump is still connected.
7. Manually start the oil pump to fill the oil lines, oil cooler and oil filter to check the "true" lubricant
level since this will lower the oil level in the sump.
8. If it is necessary to make up the lost oil in the lines then shut down the oil pump and repeat steps 5
through 7.
9. After oil charging is completed and if the oil is visible on the sight glass(es) while the oil pump is
operating, shut down the oil pump and disconnect the hand pump.
The oil heater should be immersed in oil all the time it is energized. Therefore, as a caution
de-energize the oil heater during the oil charging process to minimize the possibility of
damage to the oil heater.
When the machine is operated again, and on a regular basis during operation, the oil level
must be checked to determine if oil needs to be added to maintain the proper operating level.
Failure to do so can cause compressor damage.
Oil Analysis
The condition of compressor oil can be an indication of the general condition of the refrigerant circuit
and compressor wear. Dark color or cloudy oil, rather than clear, is an indication of contamination and
should be further investigated. An annual oil check by a qualified laboratory is essential for maintaining
a high level of maintenance. It is useful to have an oil analysis at initial startup to provide a benchmark
from which to compare future tests. Oil analysis has long been recognized as a useful tool for indicating
the internal condition of rotating machinery and continues to be a preferred method for Daikin
centrifugal chillers. The local Daikin service office can recommend suitable facilities for performing
these tests.
To accurately estimate the internal condition it is essential to properly interpret the lubricant wear
test results.
Most of the elements and contaminants in a system end up in the
solvents and can readily dissolve trace elements and contaminants. Also, the polyolester oils used in
R-134a chillers are more hygroscopic than mineral oils and can contain much more water in solution.
For this reason, it is imperative that extra care be used when handling polyolester oils to minimize their
exposure to ambient air. Extra care must also be used when sampling to ensure that sample containers
are clean, moisture-free leak proof and non-permeable.
Daikin has done extensive testing in conjunction with refrigerant and oil manufacturers and has
established guidelines to determine action levels and the type of action required. Table 22 on page 66
gives the upper limits for metals and moisture in the polyolester lubricants required by Daikin chillers.
OMM WCT
CAUTION
!
CAUTION
!
Centrifugal Chillers
oil. Polyolester oils are excellent
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