Oil Separator; Accumulators; Screens - Emerson Copeland Scroll Digital ZFD13KVE Application Manuallines

Braze connections can be converted to Rotalock by means of adaptors. Rotalock shut-off valves
are available for the suction as well as discharge side. Using either straight or angled adaptors
provides a way to convert a Rotalock into a brazing connection.
Refer to Table 6 for proper tightening torques:
Rotalock 3/4" – 16UNF
Rotalock 1" – 14UNS
Rotalock 1 ¼" – 12UNF
Rotalock 1 ¾" – 12 UNF
Table 6
NOTE: More information about adaptors and shut-off valves can be found in the "Spare
parts list".
3.7

Oil separator

During any operating cycle of Copeland Digital Scroll compressors, there is a loaded state during
which the compressor operates at full capacity. The velocity of gas during this loaded state is
sufficient to return oil back to the compressor. Laboratory tests have established that there is no
problem in oil return,
100 metres and the vertical elevation is 30 metres. Based on such performance, we do not
strictly recommend the use of an oil separator.
3.8

Accumulators

CAUTION
Inadequate lubrication! Bearing destruction! Minimise liquid refrigerant
returning to the compressor. Too much refrigerant dilutes the oil. Liquid
refrigerant can wash the oil off the bearings leading to overheating and
bearing failure.
Irrespective of system charge, oil dilution may occur if large amounts of liquid refrigerant
repeatedly flood back to the compressor during:

normal off cycles;

defrost;

varying loads.
In such a case an accumulator must be used to reduce flood-back to a safe level that the
compressor can handle. The use of accumulators is dependent on the application. If an
accumulator must be used, the oil-return orifice should be from 1 to 1.4 mm in diameter for
models ZBD21K* to ZBD57K* and ZFD13KVE to ZFD25KVE and 2.0 mm for models ZBD58K*
to ZBD114K* and ZFD41K5E, depending on compressor size and compressor flood-back
results.
The size of the accumulator depends upon the operating range of the system and the amount of
subcooling and subsequent head pressure allowed by the refrigerant control.
3.9

Screens

CAUTION
Screen blocking! Compressor breakdown! Use screens with at least
0.6 mm openings.
The use of screens finer than 30 x 30 mesh (0.6 mm openings) anywhere in the system should
be avoided with these compressors. Field experience has shown that finer mesh screens used
to protect thermal expansion valves, capillary tubes, or accumulators can become temporarily or
permanently plugged with normal system debris and block the flow of either oil or refrigerant to
the compressor. Such blockage can result in compressor failure.
C6.2.24/0215-0515/E
Torque [Nm]
40-50
70-80
110-135
135-160
even when the length of interconnecting pipe used is
13