Heatcraft Refrigeration Products PARALLEL COMPRESSOR SYSTEMS 25000102 - Manual (Page 28)

28 Part # 25000102
Installation and Operations Manual
AC&R
Model
No.
Connection
Size
Operation
Pressure
Diff., psig
Oil Level,
Sight Glass
S-9010 3 BOLT 5 - 30 1/2
S-9010A 4 BOLT 5 - 30 1/2
S-9015 3/4” NPTF F. 5 - 30 1/2
S-9090 3 BOLT 5 - 90 Adjustable
S-9090A 4 BOLT 5 - 90 Adjustable
S-9110 3 BOLT 5 - 30 1/2
S-9120 3 BOLT 5 - 30 1/4 +
S-9130 3 BOLT 5 - 90 Adjustable
S-9190 3 BOLT 30 - 90 Adjustable
Sporlan
Model
No. Of
Cores
Desiccant
Volume
(cu. in.)
# Core
Part No.
C-489-(G) 1 48
RC-4864
RC-4864-HH
RCW-48
C-969-(G) 2 96
C14411-(G) 3 144
C-19211-(G) 4 192
C-4021-(G) 4 192
C-4025-(G) 4 192
Troubleshooting Oil System
The oil return line should always be checked. Feeling the oil
return line and seeing how often it gets hot is the main way to
tell if the separator is working properly. It is easier if an oil line
sight glass is installed, mainly because if the oil line is hot you
don’t know if it is oil or hot gas causing it to be hot. If the oil
line cycles between hot and cold at least a few times per hour,
the separator is most likely working properly. The float tends to
open and feed a few ounces of oil at a time and shut until the
oil builds back up. If the oil return is cycling there is no need to
drain the separator to look at the float components.
Always check the oil reservoir level during a service call. Oil
levels in the reservoir will normally vary during periods of
varying loads: compressors shutdown, hot-gas defrost, etc. This
is normal, however if the level is consistently low or high, the
oil system should be checked thoroughly.
Compressor oil levels can be deceiving. It is sometimes hard
to tell if the regulator is feeding oil or if oil is coming down the
suction line. If the reservoir has too much pressure, often times
this pressure will force oil out of the regulator and show a low
level, even though there may be excessive oil in the compressor.
Many times the best way to check the oil in the compressor is to
shut off the oil feeding to the regulator while the compressor
is operating and wait a few minutes. If oil is pushed out of the
regulator or trapped in the motor cavity on semi-hermetic
models, the compressor will overfill.
The oil line sight glass is a good way to see how the separator is
working. Look for movement in the glass. If the separator is not
feeding on single or low pressure systems, the sight glass will
have little or no movement and normally will appear empty. If
the separator is feeding, the sight glass will show a rush of oil
and foam past the glass. Most of the time, viewing this sight
glass can prevent having to open the system.
To check the oil level in the separator if the separator has a drain,
shut off the oil return line to prevent further feeding, pump
down the system, shut off the system, evacuate the separator,
and drain the oil from the bottom.
The separator should hold the pre-charge amount plus or minus
a few ounces during operation. By looking at the amount above
or below the pre-charge, any problem with the separator or
float can be determined.
Note that there is no way to clean or repair welded oil separators.
If it is determined that the float is clogged or otherwise
malfunctioning, the entire oil separator must be replaced.
When the refrigerant and/or oil types are changed in a system,
there is the potential for leaks around o-ring seals. Most
elastomers absorb oil and refrigerant and may swell or shrink
when exposed to a new oil or refrigerant. In these cases replace
the o-rings and seals in the system as needed.
Liquid Filter-Driers & Suction Filters
A replaceable core liquid filter/drier is supplied as standard
on all Rack units and is an option in all other parallel systems.
A Schrader type access valve is installed in the flange plate of
some models. The liquid cores are always shipped loose for
field installation. (See No. 5 of Leak Checking, Evacuation, and
Start-up section in this manual).
Table 22. AC&R Model Regulators
Table 23. Sporlan Valve Co.
Table 24. Alco Controls
“G” indicates flange plate supplied with _” FPT
# “RC__” Standard Core, “RC__HH” Burnout Core
“RCW_” High Water Capacity
* “T” indicates Liquid Line Service
# “D” Standard Capacity, “H” High Capacity
”UK” High Capacity, “W” Burnout Block
Alco
Model
No. Of
Cores
Desiccant
Volume
(cu. in.)
# Core
Part No.
STAS-489-T* 1 48
D-48
H-48
UK-48
W-48
STAS-969-T 2 96
STAS-14411-T 3 144
STAS-19211-T 4 192
STAS-19213-T 4 192
STAS-19217-T 4 192