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6.4 Installation for the first time
Air and moisture in the refrigerant system have undesirable effects as below:
●
Pressure in the system rises.
●
Operating current rises.
●
Cooling or heating efficiency drops.
●
Moisture in the refrigerant circuit may freeze and block capillary tubing.
●
Water may lead to corrosion of parts in the refrigerant system.
Therefore, the indoor units and the pipes between indoor and outdoor units must be leak tested
and evacuated to remove gas and moisture from the system.
Gas leak check (Soap water method):
Apply soap water or a liquid neutral detergent on the indoor unit connections or outdoor unit
connections by a soft brush to check for leakage of the connecting points of the piping. If bubbles
come out, the pipes have leakage.
1. Air purging with vacuum pump
1). Confirm that both the 2-way and 3-way valves are set to the opened position.
Remove the valve stem caps and confirm that the valve stems are in the opened position.
Be sure to use a hexagonal wrench to operate the valve stems.
2). Connect the charge hose with the push pin of handle lo to the 3-way valves gas service port.
(Indoor unit)
(Liquid side)
(Gas side)
Vacuum
pump
Vacuum
pump
Lo
Hi
Handle Hi
Two-way valve
Close
Manifold valve
Compound meter
Pressure
gauge
20Pa
Handle Lo
Charge hose
Charge hose
(Outdoor unit)
Close
Three-way valve
