Specifications

EDUS281104 Installation of indoor unit
Installation of indoor / outdoor unit 93
3PN06240-3E
8
7-2 Connecting the refrigerant pipe
• When connecting the flare nut, coat the flare both inside and
outside with ester
oil or ether oil and initially tighten by hand 3
or 4 turns before tightening firmly.
• To prevent flare nut cracking and gas leaking, be sure to use
both a spanner and torque wrench together, as shown in the
drawing below, when connecting or disconnecting pipes to/
from the unit.
• Refer to the Table 3 for the dimensions of flare shape.
• Refer to the Table 3 to determine the proper tightening
torque.
Tabl e 3
NOTE
• Apply ester oil or ether oil around the flare portions before
connecting.
• The flare nuts used must be those included with the main
body.
• Over-tightening may damage the flare and cause a refriger-
ant leakage.
Not recommended but in case of emergency
You must use a torque wrench but if you are obliged to
install the unit without a torque wrench, you may
follow the installation method mentioned below.
After the work is finished, make sure to check that
there is no gas leak.
When you keep on tightening the flare nut with a spanner,
there is a point where the tightening torque suddenly
increases. From that position, further tighten the flare nut
the angle shown below:
Table 4
7-3 Piping insulation
• Execute heat insulation work completely on both sides of the
gas pipe and the liquid pipe. Otherwise, a water leakage can
result sometimes.
• The temperature of the gas pipe can reach up to approxi-
mately 250°F, so use insulation which is sufficiently resistant.
•
Also, in cases where the temperature and humidity of the refrig-
erant pipe sections might exceed 86°F or RH80%, reinforce the
refrigerant insulation. (13/16 in. or thicker) Condensate may
form on the surface of the insulating material.
• Check the pipe connector for gas leaking, then insulate it as
shown in the drawing below.
• Make absolutely sure to execute heat insulation works on the
pipe-connecting section after checking gas leakage by thor-
oughly studying the following figure and using the attached
heat insulating materials for fitting. (Fasten both ends with
the clamps (accessory).)
• Wrap the sealing pad (accessory) only around the insulation
for the joints on the gas pipe side.
CAUTION
• Be sure to insulate any field piping all the way to the piping
connection inside the unit. Any exposed pipe may cause
condensate or burns if touched.
Pipe
size
(in.)
Tightening torque
(ft.lbf)
Flare
dimensions
A (in.)
Flare shape (in.)
φ 3/8 24.1 – 29.4 0.504-0.520
φ 5/8 45.6 – 55.6 0.760-0.776
Ⳳ
Ⳳ
Pipe size
(in.)
Further tightening
angle
Recommended arm length of
tool (in.)
φ 3/8 60 to 90 degrees Approx. 7 7/8
φ 5/8 30 to 60 degrees Approx. 11 13/16
Be sure to use insulation that is designed for use with
HVAC Systems.
Be sure to use insulation that is designed for use with
HVAC Systems.