10
WARNING
● It is forbidden to discharge refrigerant into the atmosphere. Collect the refrigerant in accordance with the
Freon collection and destruction law.
● If the refrigerant gas leaks during installation work, ventilate the room immediately.
● Do not use flux when brazing the refrigerant piping. For brazing, use phosphor copper brazing filler metal
(BCuP) which does not require a flux.
CAUTION
● If being put aside for ling period after end caps being removed, breakdown may happen to tubes
because of invasion of dust, water and foreign matter into pipe, so please proceed connection
operation as following rapidly.
● Before tightening flare nuts, a layer of attached cooling engine oil should be thinly applied on the sealed
pad surface between tubes and connectors.
● Please proceed tubing connections with two wrenches and refer to table 4 for tightening torque.
● Please apply attached refrigerant lines thermal insulation materials for insulation on indoor lateral flare
connection areas.
Attentions on application of flexible couplings:
1)Please apply flexible coupling at indoor lateral interconnecting areas.
2)Bending angle cannot exceed 90°, and bending cannot be repeated more than 3 times.
3)To reach appropriate torque as per torque wrench:
Table
4
Piping
procedure:
1)Keep stop valve on outdoor unit in “off” status (ex-factory specification) as original, dismantle end caps on
refrigerant lines and the unit, and proceed quickly flare connection.
2)Leakage test. For details,please refer to chapter 8.8 Leakage test.
3)Vacuum the system. For details, please refer to chapter 8.9 Vacuum process.
4)Addition refrigerant charge. For details,please refer to chapter 8.10 addition refrigerant charge.
5)After completion of above operation, keep stop valve (commonly used by liquid and gas) on the outdoor unit
totally open. By then, refrigerant cycle between indoor unit is all connected.
Tube diameter
(mm)
tightening torque,
approximate
Tube thickness
(mm)
Φ6.35
14-18 N.m
(140-180kgf.cm)
0.8
Φ9.52
34-42 N.m
(340-420kgf.cm)
0.8
Φ12.7
49-61 N.m
(490-610kgf.cm)
0.8
Φ15.88
68-82 N.m
(680-820kgf.cm)
1.0
Φ19.05
100-120 N.m
(1000-1200kgf.cm)
1.0
8 refrIGerANT pIpING
