AGL_Stream_ST_A2L_A1_4M_6M_EN_Rev00
9
Once a new system design is set and assembled, a functional test is required. The functional test
includes a qualification for the general system oil return. Systems with multiple compressors (two,
three, or more) require additional oil balancing qualification between the parallel compressors.
System engineers should review the system design and operation to identify the critical conditions
and to check oil return and oil balancing. Typically, the following situations should be considered:
▪
In single compressor systems:
to check oil return, testing conditions shall be at minimum mass
flow and minimum density of suction gas in continuous and frequent start/stop-cycling.
▪
In multiple compressor systems:
to check oil return and oil balancing in the tandem or rack,
testing conditions shall be at the corner points of the system application envelope in continuous
and frequent start/stop-cycling.
▪
The system shall also be tested with regards to liquid refrigerant floodback and the superheat
level of the refrigerant gas at compressor suction.
These checks should be carried out for standard operation, but also for special conditions such as
compressor frequent start/stop, compressor start after long off time with migration, defrost, low load,
load changes, fans or pumps cycling at low load and more.
2.6 Dimensions of Stream compressors
2.6.1 4M* models
Figure 9: 4M* compressors dimensions
Compressor
A
(mm)
B
(mm)
C
(mm)
D
(mm)
G
(mm)
4MF-13X
4MA-22X
4ML-15X
637
145
88.5
355.9
354.6
4MH-25X
4MM-20X
4MM-20X
662
170
99.4
376.2
354.8
4MT-22X
4MJ-33X
4MU-25X
662
170
99.4
376.2
354.8
4MK-35X
692
200
131.4
380
354.8
Table 4: 4M* compressors dimensions
