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2.1 Oil Separator and Oil Return
All 06CC model compressors have lower oil circulation
rates than single-stage compressor models however;
these systems do circulate some oil in mixture with refrig-
erant. It is important to properly size oil separators to effi-
ciently remove oil from the discharge refrigerant flow.
Incorrectly sized oil separators can result in higher per-
centages of oil bypassing the oil separator, leading to oil
'logging' in the system and oil 'slugs' being returned to
the compressors. This condition is undesirable for all
compressor types and must be avoided for the two-stage,
06CC models. Oil 'slugs' that return in the suction line
enter the low-stage cylinders of the 06CC models and
have a higher potential for causing damage. Carlyle
requires the use of a high-efficiency oil separator in all
06CC model applications. Preferable oil separator
designs provide increased efficiency as mass flow rates
decline. For HFC refrigerant applications, Carlyle recom-
mends oversized (125% to 150% of design loads),
coalescing or impingement type oil separator designs.
2.2 Oil Equalization
The 06CC model compressor types must not be applied
with motor barrel equalization or crankcase equalization
(through the floats). This requirement applies to the
two-stage, 06CC model compressors only, not the 06D/E
single-stage models.
2.3 Oil Pressure Safety Switch
All Carlyle 06CC models are provided with connections
for oil pressure safety switches. All 06CC model com-
pressors are provided with connections for low oil pres-
sure protection. Low oil pressure protection is required as
a condition of warranty for all 06CC model compressors.
Low oil pressure protection can help to prevent compres-
sor failures due to loss of lubrication or insufficient oil
level within the compressor. Normal oil pressure for the
06CC models is between 18 psig and 34 psig above the
interstage pressure. Oil pressure safety switches (OPSS)
must be of the manual-reset type. For HFC / POE appli-
cations, Carlyle recommends the use of oil pressure
safety switches that have time-delay of 120 seconds.
2.4 Oil
Carlyle's 06CC model compressors are shipped without
oil. When applying 06CC model compressors, Carlyle
approved oils must be applied. The list below details the
Carlyle approved oils for use in 06CC model applications.
For CFC Refrigerants:
Witco - Suniso 3GS
IGI Petroleum IND - Cryol 150
Shrieve Chemical - Zerol 150
Texaco Capella - WFI-32-150
Totaline - P903-2001
For HFC Refrigerants:
CPI - Solest 68
ICI - Emkarate RL68H
Castrol - E68
Totaline - P903-1701
Important!
The crankcase of the two-stage, 06CC models is
at an intermediate pressure. The oil reservoir
must be vented (a 20 lb check valve is recom-
mended) to the interstage manifold, NOT to the
suction manifold as is typical with single-stage
compressors. Oil return to the 06CC model com-
pressors must be done at the crankcase of the
compressor, NOT to the suction line.
2.0 Compressor Lubrication System
