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9.5 SCREENS
Screens with a mesh size finer than 30 x 30 (0.6mm openings) should not be used anywhere in the system
with scroll compressors.
9.6 LIQUID INJECTION
Scroll compressor for LBP application is supplied with an injection port suitable for connection to a
liquid refrigerant source. This port is connected to an inner pocket of the scroll mechanism. As pocket is
perorated from the suction inlet, there is no loss of replacement capacity results from injection at this point.
Refrigerant injected in this manner must include the system components listed on the following instructions.
Failure to follow these instructions can result in liquid refrigerant completely filling the
scroll during an “off” cycle. When power is reapplied in this condition, the hydraulic
effect produced can result in pressures high enough to cause permanent damage to
the compressor scroll sets. It is a condition of warranty that these components are
properly installed.
The advantage of this type of injection system is that it tends to be self regulating i.e., as the pressure
differential across the capillary tube increases, the amount of liquid fed to the compressor also increases.
Since more cooling is needed at high compression ratio conditions, this “automatic” increase in liquid
feed is exactly what is needed. For the liquid injection system to be effective, a minimum of 3K sub-
cooled liquid at the capillary inlet is required. However, DO NOT use mechanically cooled sub-cooled
liquid. The cap tube will be oversized under this condition and will dilute the oil in the compressor shell.
IMPORTANT
SIGHT GLASS
SOLENOID VALVE
FILTER
DRIER
RECEIVER
DTC VALVE
SCROLL
COMPRESSOR
CONDENSER
EVAPORATOR
