Table of Contents
Advertisement
● Cautions for Piping Connection Work
(a) Connect the indoor/outdoor connecting
pipes. Secure the pipes and do not touch
other objects, such as ceilings for example.
(Otherwise, abnormal sound may be heard
due to the vibration of the piping.)
(b) Apply refrigerant oil slightly on the sheet
surface of the pipe and flare nut before the
flaring work. Then tighten the flare nut with
the specified tightening torque using two
wrenches. Always use a back-up wrench to
prevent twisting of the copper piping within
the unit assembly. Perform the flaring work
on the liquid piping side before the gas
piping side. Check the gas leakage after the
flaring work.
NOTE:
Refrigerant oil is field-supplied
[Ethereal Oil FVC50K, FVC68D (Idemitsu
Kousan Co. Ltd.)]
(c) When temperature and humidity inside the
ceiling exceed 27
humidity, 80%, apply additional insulation
approximately 20mm (13/16 inch) thickness
to the accessory insulation. It prevents
condensation on the surface of the insulation
(refrigerant pipe only) and possible damage
to electronic components.
(d) Perform the air-tight leakage test 4.15MPa
(601 psi) for the test pressure. Refer to the
Technical Manual for the Outdoor Unit for
more details.
(e) Perform cold insulation work by insulating
and taping the flare connection and reducer
connection. Also insulate all the refrigerant
pipes.
Apply Refrigerant Oil.
Required Tightening Torque
Pipe Size
6.35mm (ɸ1/4 inch)
9.52mm (ɸ3/8 inch)
12.7mm (ɸ1/2 inch)
15.88mm (ɸ5/8 inch)
19.05mm (ɸ3/4 inch) 100 to 120 N
o
C(80
o
F) /RH, relative
Two wrenches required to prevent
damaging the copper piping.
Tightening Torque
m (10.3 to 13.3 ft . lbs)
14 to 18 N
●
m (25.1 to 31.0 ft . lbs)
34 to 42 N
●
m (36.1 to 45.0 ft . lbs)
49 to 61 N
●
m (50.2 to 60.5 ft . lbs)
68 to 82 N
●
m (73.8 to 88.5 ft . lbs)
●
● Do not apply excessive force to the flare
nut when tightening. Excessive force can
result in the flare nut cracking and refrigerant
leakage may occur. Use the specified
tightening torque.
● For more details of the refrigerant piping
work, vacuum pumping and refrigerant
charge, refer to the Technical Manual for the
Outdoor Unit.
12
Advertisement
Table of Contents
