through the solenoid valve (1), filter-drier, sight glass, second
solenoid valve (2), an expansion device, and then goes to the
evaporator. Another fan blows air over the evaporator. The
refrigerant returns to the compressor through the suction line.
The liquid refrigerant passes through the solenoid valve (4),
and then enters the accumulator. The accumulator is connected to the refrigeration system by top (for vapor refrigerant) and bottom side (for liquid refrigerant). It has a column
indicating the refrigerant level. When the solenoid valve (5) or
(6) is opened, the refrigerant is added to the system. When the
solenoid valve (3) is opened, the refrigerant bypasses the
suction line