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Indoor unit
Extension pipe diameter (mm/inch)
Model
Pipe diameter (mm/inch)
9K/12K
Liquid
6.35(1/4)
Liquid
6.35(1/4)
Gas
9.52(3/8)
Gas
9.52(3/8)
18K
Liquid
6.35(1/4)
Liquid
6.35(1/4)
Gas
12.7(1/2)
Gas
12.7(1/2)
Outdoor unit union diameter (mm/inch)
Indoor unit A/B/C/D
Liquid
6.35(1/4)
Gas
9.52(3/8)
10.4 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
Summary of Contents for 38QUS018DS2 Series
Page 16: ...16 78 3 4 A5 Duct ...
Page 19: ...19 78 ...
Page 20: ...20 78 5 Wiring Diagram Outdoor 38QUS018DS2 Outdoor 38QUS027DS3 ...
Page 21: ...21 78 Outdoor 38QUS036DS4 High wall 42QHF009DS 42QHF012DS 42QHF018DS ...
Page 22: ...22 78 A5 Duct 42QSM009DS A5 Duct 42QSM012DS 42QSM018DS ...
Page 23: ...23 78 Four way cassette 42QTD009DS Four way cassette 42QTD012DS 42QTD018DS ...
Page 24: ...24 78 Console ...