5.4 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
(Indoor unit)
Compound meter
Handle Lo
Charge hose
Vacuum
pump
Vacuum
pump
(Liquid side)
(Gas side)
Manifold valve
-0.1MPa
Lo
Hi
Charge hose
Two-way valve
Three-way valve
Pressure
gauge
Handle Hi
16
(Outdoor unit)
Close
Close