Kaisai KFU-09HRDN1-QRC8GW, Service Manual

Page: 21 / 69

21
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)
Completely tighten the flare nuts of the indoor and outdoor units, confirm that both the 2-way and 3-way
valves are set to the closed position.
2)
Connect the charge hose with the push pin of handle lo to the 3-way valves gas service port..
3)
Connect the charge hose of handle hi connection to the vacuum pump.
4)
Fully open the handle Lo of the manifold valve.
(Indoor unit)
(Liquid side)
(Gas side)
Vacuum
pump
Vacuum
pump
Lo Hi
Handle Hi
Two-way valve
Close
Manifold valve
Compound meter
Pressure
gauge
-0.1MPa
Handle Lo
Charge hose
Charge hose
(Outdoor unit)
Close
Three-way valve