2.2 Vapor Temperature Limits
Any application of screw compressors must
operate within the limits defined by the appli-
cation maps for the various refrigerants and
applications.
Vapor Temp.
Min.
Max.
Suction
10°F SH*
100°F
(6°C)
(38°C)
Economizer
Saturated**
Non-
Vapor
Economized
*SH = Superheat
**The maximum economizer pressure allowable is
175.3 psig (13.1 bar)
2.3 Minimum Oil Pressure Differential
A minimum pressure differential of 45 psi
(3 bar) is required between suction and oil
pressure (at the compressor). Applications
below this minimum range will require the
use of an external oil pump.
2.4 Operating Speed Ranges
The operating speed range for the screw com-
pressor is as follows for the different size range
compressors.
Model
ft
3
/
m
3
/
Min.
Max.
No.
min
min
Hz
Hz
06T**033 33
0.93
50
70
06T**039 39
1.10
40
70
06T**044
44
1.26
35
70
06T**048
48
1.36
30
70
06T**054
54
1.53
30
70
06T**065
65
1.84
25
70
06T**078
78
2.21
20
68
06T**088
88
2.49
20
60
06T**108
90*
2.56*
20
50
* 50 Hz Applications only.
7
R-507-R404A APPLICATIONS
Saturated Discharge
T
emperature deg F (deg C)
120
60
140
0
20
40
80
100
(60)
(49)
(38)
(27)
(16)
(4)
(-7)
(-18)
-40
-35
-30
-25
-20
20
-15
-10
-5
0
5
10
15
25
30
35
(-40) (-37) (-34) (-32) (-29) (-26) (-23) (-21) (-18) (-15) (-12) (-9)
(-7) (-4)
(-1)
(2)
Saturated Suction Temperature deg F (deg C)
-45
(-43)
(-46)
-50
Oil Cooling Control
Disch T
emp
Control
R-507/R404A APPLICATIONS