Oil Separator For Active System - Danfoss MLM116 Application Manuallines

Application Guidelines
Oil separator and
reservior for active
system
System design recommendations
When an active system is adopted by the
customer, the oil separator is always considered
together with oil reservoir.
Active system
Non-return
valve
Suction
header
Compressor 1
Oil level regulator
Danfoss recommends that high-pressure
systems (oil separator installed in high pressure
side) are configured in active solutions. These
systems store the oil in a common oil separator/
reservoir at compressor discharge pressure (see
the figure below). The advantage is that these
systems do not need a separated oil reservoir but
make use of a combined oil separator/reservoir
arrangement ,which normally results in a cost
saving over traditional low-pressure systems
(additional oil separator and oil reservoir installed
in low pressure side). From an application point
Due to system design, loads and defrost
cycles, etc., there will be varying amounts of oil
returning to the oil separator. Because of this,
a safety reserve of oil is required for successful
operation of the active system.
Non-return Non-return
valve valve
Compressor 2 Compressor 3
Oil level regulator Oil level regulator
of view, high-pressure systems are more critical
than traditional low pressure systems and care
must be taken to make sure that the separator/
reservoir installed is of sufficient size and oil
content (as per manufacturer's recommendation)
so that there is always oil stored. And pay special
attention to avoid discharge gas entering the
compressor oil sump, which could lead to some
negative effects such as higher discharge and oil
temperatures, less lubrication capability and the
loss of efficiency due to hot gas bypass.
Manifold compressors
High pressure
Low pressure
Non-return Non-return
valve valve
Combined oil
Compressor 4
separator/reservoir
Oil level regulator
Oil lter
FRCC.PC.035.A4.02
49