LB
II
-PLUS Technical Manual
19
2.3.4
Economizer
The economizer will further cool the refrigerant before it pass through the expansion valve of the system, which
increases the cooling capacity and efficiency of the system, especially in the working condition of high condensation
and low evaporation temperature.
Sub-cooling cycle economizer:
A heat exchanger is used as a liquid sub-cooling device to achieve the purpose of sub-cooling of liquid
refrigerant. A portion of the refrigerant will be drawn from the condenser pipe, which will enter the sub-cooler
through the expansion valve, absorbing the heat and evaporating, and exchange heat with the backflow liquid
refrigerant. After heat absorption, the superheated saturated vapor enters the medium pressure compression
section through the compressor's economic interface for compression. This type can effectively improve the quality
of the liquid refrigerant refrigeration unit, and at the same time, the discharge temperature can be effectively
reduced.
The selection of economizer:
The tube and shell type heat exchanger can be used as an economizer. Please select the load of the
economizer according to the relevant technical data in the HANBELL software.
The selection of economizer expansion valve:
If you want to get more valve selection guidance for economizer expansion valves, please contact
HANBELL.
The control model of economizer:
It is suggested that when the system starts to run stable, the high and low pressure ratio is greater than 3
or the low pressure side pressure reaches the set value, then the economic cycle can be opened in order
to avoid the lubricating oil in the compressor back to the economizer, producing extra vibration and noise,
even the crack of the pipe.
Figure - Economizer pipe diagram
