Sinclair SDV5 Series Service Manual page 10

Figure 2-1.3: 140/160 model Piping diagram
Key components:
1. Oil separator:
Separates oil from gas refrigerant pumped out of the compressor and quickly returns it to the compressor. Separation
efficiency is up to 99%.
2. Gas-liquid separator:
Stores liquid refrigerant and oil to protect compressor from liquid hammering.
3. Electronic expansion valve (EXV):
Controls refrigerant flow and reduces refrigerant pressure.
4. Four-way valve(ST1):
Controls refrigerant flow direction. Closed in cooling mode and open in heating mode. When closed, the heat
exchanger functions as a condenser; when open, the heat exchanger functions as an evaporator.
5. High and low pressure switches:
Regulate system pressure. When system pressure rises above the upper limit or falls below the lower limit, the high or
low pressure switches turn off, stopping the compressor. After 5 minutes, the compressor restarts.
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