AE4-1322
© 2002 Copeland Corporation
Issued 4-2002
Printed in U.S.A.
12
Air cooled oil cooler
Air cooled oil cooler
Air cooled oil cooler
Air cooled oil cooler
Air cooled oil cooler
Temperature control by thermostatic switching on and
off or stepless speed control of the cooler fan (see
table for set point, required sensor temperature should
be equal to or greater than 250°F).
If the oil coolers is integrated into the condenser the
by-pass valve controls the temperature (see table for
set point; admissible operating and / or sensor tem-
perature should be equal to or greater than 250°F).
Thermosyphon oil cooling (cooling by refrigerant)
Thermosyphon oil cooling (cooling by refrigerant)
Thermosyphon oil cooling (cooling by refrigerant)
Thermosyphon oil cooling (cooling by refrigerant)
Thermosyphon oil cooling (cooling by refrigerant)
Temperature control either by thermostatic regulation
valve for refrigerant feed or by-pass valve (see table for
set point; admissible operating and sensor temperature
should be equal to or greater than 250°F).
As an example figure 11 shows a layout with a primary
receiver after the condenser. An alternative layout of the
thermosyphon circuit as well as refrigerant circulation
by means of a pump or an ejection is also possible
(information upon request).
4 Economizer operation
1.1 General
1.1 General
1.1 General
1.1 General
1.1 General
SCH2/SCA2 screw compressors are designed for
economizer operation “ECO”. With this operation mode
both cooling capacity and efficiency are improved by
means of a sub-cooling circuit or 2-stage refrigerant
expansion. There are capacity and efficiency advan-
tages in ECO operation over the conventional applica-
tion, particularly at high condensing temperatures.
A unique feature of the compact screws is the econo-
mizer channel integrated into the control slide (fig.12).
This enables to operate the sub-cooling circuit regard-
less of the compressor load condition. Screw com-
pressors with a fixed ECO suction position have this
frequently located in the suction area of the rotors
during part load and then has no effect.
Figure 9
Water-cooled oil cooler
Figure 11
Thermosyphon oil cooling
Figure 10
Air cooled oil coolers
DL
SL
