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WA900-3EO
COMMISSIONING
SYSTEM EVACUATION
- Overview
A moisture free refrigerant system is essential for the correct
functioning of the unit. Moisture can cause freezing and
blockage at control points, etc, or the formation of
hydrochloric acid when in contact with refrigerant, with
detrimental effects upon valves, bearings, seals, etc.
The manifold has fittings to receive the gauges and hoses
and hand valves, which provide control of the refrigerant
through the manifold. The manifold gauges are connected to
the compressor service valves by hoses.
The high side gauge measures pressure on the discharge
side of the compressor.
The low side gauge registers both pressure and vacuum. The
vacuum side is utilised to record the vacuum pulled, during
evacuation of the system, in inches of mercury. The pressure
portion of the gauge scale is used to record the pressure on
the suction side of the compressor during unit operation.
The hand valves are utilised to open or close the gauge
pressure ports. When the valve is turned all the way in
(clockwise), the manifold port is closed and the pressure
gauge is open to the pressure hole. The pressures on that
side of the system will be recorded on the gauge above the
hose. Opening the valve fully (anti-clockwise) opens the
system to the middle service port of the manifold set. This is
done only to let refrigerant into or out of the system, or for
evacuating the system.
Refer to the diagram right for correct connection of
evacuation circuit components.
COMMISSIONING
