Embraco Scroll SE2006GK-C, Руководство по установке

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9.7 SOLENOID VALVE
A solenoid valve with a minimum 3mm orifice must be provided in the injection circuit that opens whenever
the compressor is operative or cooling is required during pump down. The solenoid must be closed when
the compressor is cycled off.
Note: Not required if DTC valve is used.
9.9 TEMPERATURE RESPONSIVE EXPANSION VALVE (TXV)
It is possible to use a TXV (temperature responsive expansion valve) valve to realize the liquid
injection. When the discharge temperature is higher than the settings, the valve will open. Based
on discharge temperature detected by the bulb, valve opening degree is set. Liquid refrigerant will be
fed into the injection port; the injection flow will change according to the discharge temperature.
The purpose of this valve is to eliminate the need for a capillary tube on the LBP scroll model family.
Suggested valve specifications: Opening Setpoint: 90°C ±3°C
The valve bulb must be installed properly on the thermal top cap to adequately control scroll temperatures.
The valve should be tightened on the injection fitting to a torque of 25 - 28 Nm.
A 90° orientation on the valve is recommended, however it will function properly in any orientation.
Avoid contact of capillary tube (connecting the valve to the bulb) with compressors during operation. Do not
bend the capillary tube within 25mm of the valve.
9.8 CURRENT SENSING RELAY
To prevent the solenoid valve from remaining open during a motor protector trip, current sensing relay must
be sensitively designed to act whenever the compressor is off, and closes the solenoid to stop injection.
Note: These parts are Not required if DTC valve is used.
The following components are not required, but they are recommended for liquid injection:
• Sight Glass just before the capillary tube inlet is recommended to allow visual inspection for the presence
of liquid refrigerant.
• Filter/Drier installed in the injection circuit is recommended to avoid the possibility of capillary tube
blockage due to contaminants.