RLC-SVX14H-GB
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6. If the level is below 10cm, there is not enough oil
in the sump. This can occur from not enough oil
in the system or more likely, oil migration to the
evaporator. Oil migration can occur from a low
refrigerant charge, gas pump malfunction, etc.
Note: If the oil is logged in the evaporator confi rm
the operation of the gas pump. If the gas pump is
not functioning properly all oil will be logged in the
evaporator.
7. After the level is determined, close the service valves
and remove the hose/sightglass assembly.
Removing Compressor Oil
The oil in the compressor oil sump is under a constant
positive pressure at ambient temperature. To remove
oil, open the service valve located on the bottom of the
oil sump and drain the oil into a suitable container using
the procedure outlined below:
CAUTION POE Oil!
Due to the hygroscopic properties of the POE oil, all oil
must be stored in metal containers. The oil will absorb
water if stored in a plastic container.
Oil should not be removed until the refrigerant is
isolated or removed.
1. Connect a line to the oil sump drain valve.
2. Open the valve and allow the desired amount of oil to
fl ow into the container and close the charging valve.
3. Measure the exact amount of oil removed from
the unit.
Oil Charging Procedure
It is critical to fi ll the oil lines feeding the compressor
when charging a system with oil. The diagnostic “Loss
of oil at the compressor stopped” will be generated if
the oil lines are not full on start-up.
To properly charge the system with oil, follow the steps
below:
1. Locate the 1/4” schrader valve on the end of the
compressor.
2. Loosely connect oil pump to schrader valve called out
in step 1.
3. Operate oil charging pump until oil appears at
the charging valve connection; then tighten the
connection.
Note: To keep air from entering the oil, the charging
valve connection must be air- tight.
4. Open the service valve and pump in the required
amount of oil.
Note: Adding oil at the oil charging port ensures that the
oil fi lter cavity and the oil lines back to the oil separator
are fi lled with oil. An internal oil valve prevents oil from
entering the compressor rotors.
Replacing the Oil Filter
The fi lter element should be changed if the oil fl ow is
suffi ciently obstructed. Two things can happen: fi rst, the
chiller may shut down on a “Low Oil Flow” diagnostic,
or secondly, the compressor may shut down on a “Loss
of Oil at Compressor (Running) diagnostic.
If either of these diagnostics occurs, it is possible the oil
fi lter needs replacement. The oil fi lter is not usually the
cause of a Loss of oil at Compressor diagnostic.
Specifi cally, the fi lter must be changed if the pressure
drop between the two service valves in the lubrication
circuit exceeds the maximum level as given in
Figure 24. This chart shows the relationship between
the pressure drop measured in the lubrication circuit
as compared with operating pressure differential of the
chiller (as measured by pressures in the condenser and
evaporator).
Normal pressure drops between the service valves of
the lubrication circuit are shown by the lower curve.
The upper curve represents the maximum allowable
pressure drop and indicates when the oil fi lter must be
changed. Pressure drops that lie between the lower and
upper curves are considered acceptable.
For a chiller equipped with an oil cooler, add 0.3 bar
to the values shown in Figure 24. For example, if the
system pressure differential was 5.5 bar, then the clean
fi lter pressure drop would be approximately 1 bar
(up from 0.7 bar). For a chiller with an oil cooler and
operating with a dirty oil fi lter, the maximum allowable
pressure drop would be 1.9 bar (up from 1.6 bar).
Under normal operating conditions the element should
be replaced after the fi rst year of operation and then as
needed thereafter.
Service and Maintenance
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