Piping Connections - York TIWM006B21S Installation And Maintenance Manual

6.2

Piping Connections

(1) Perform the flaring work as shown below.
(2) Use specific flare nut attached with the unit.
(3) Verify that there are no scratches, burrs stuck to internal surfaces, or surface deformations at the flared
opening.
(4) Before tightening the flare nut, apply the (Field-Supplied) refrigerant oil in a thin layer over the flared
part. (Do not apply the oil on other areas.) Tighten the flare nut for the liquid pipe to the specified
torque with two spanners. Then, tighten the flare nut for the gas piping in the same way. After the
tightening work has been completed, check that no refrigerant leakage occurs.
NOTE:
Refrigerant oil is field-supplied.
[ Ethereal Oil FVC50K, FVC68D (Idemitsu Kousan Co. Ltd.) ]
Apply Refrigerant Oil.
Do not apply
the refrigerant
oil to the
outside of the
flaring opening.
(5) Wherever buried piping exists on site, make sure there is a service doorway to provide adequate
access to inspect piping sockets and elbows, and for interconnecting parts.
(6) Piping must be reinforced to withstand earthquakes so as not to be damaged by an external force.
(7) Do not tightly secure refrigerant piping to accommodate expansion and contraction.
(8) Prevent the pipes from contacting weak portions such as wall, ceiling, etc. (Otherwise, abnormal sound
may be heard due to vibration of the piping.)
(9) Leak test all piping and connections. The procedures should be performed in accordance with the
"Installation and Maintenance Manual" for the outdoor unit.
(10) Insulate each flare connection without gap with accessory insulations to prevent condensation. Then
insulate each refrigerant pipe as well.
Insulation for Indoor Piping Connection
Wrap the pipe insulation accessory around the flare connection and secure it with tape as shown in the
figure below.
P5417052
+ 2
90
o o
fA
0.4 ~ 0.8R
fd
Use two wrenches for
tightening the flare nut.
Pipe Insulation
(Accessory)
Diameter
(d)
1/4 (6.35) 0.36 (9.1)
3/8 (9.52) 0.52 (13.2)
1/2 (12.7) 0.65 (16.6)
5/8 (15.88) 0.78 (19.7)
Required Tightening Torque
Pipe Size
1/4 inch (6.35 mm) 10.3 - 13.3 ft·lbs (14 - 18 N·m)
3/8 inch (9.52 mm) 25.1 - 31.0 ft·lbs (34 - 42 N·m)
1/2 inch (12.7 mm) 36.1 - 45.0 ft·lbs (49 - 61 N·m)
5/8 inch (15.88 mm) 50.2 - 60.5 ft·lbs (68 - 82 N·m)
inch (mm)
0
fA
-0.02 (-0.4)
(JIS B 8607)
Tightening Torque
19