12
EN
Digital Inverter
Tightening of Connecting Part
1. Align the centers of the connecting pipes and fully tighten
the flare nut with your fingers. Then fix the nut with a
wrench as shown in the figure and tighten it with a torque
wrench.
2. As shown in the figure, be sure to use two wrenches to
loosen or tighten the flare nut of the valve on the gas
side. If you use a single crescent, the flare nut cannot be
tightened to the required tightening torque.
On the other hand, use a single crescent to loosen or
tighten the flare nut of the valve on the liquid side.
(Unit: N•m)
CAUTION
1. Do not put the crescent wrench on the cap or cover.
The valve may break.
2. If applying excessive torque, the nut may break
according to some installation conditions.
•
After the installation work, be sure to check for gas leaks
of the pipe connections with nitrogen.
•
Pressure of R410A is higher than that of R22 (Approx.
1.6 times).
Therefore, using a torque wrench, tighten the flare pipe
connecting sections that connect the indoor/outdoor units
at the specified tightening torque.
Incomplete connections may cause not only a gas leak,
but also trouble with the refrigeration cycle.
Branch Pipe
Carry out the refrigerant piping work using the branch pipe kit
which is purchased separately.
Branch pipe installation
Length of straight sections on main pipe side of
branch pipe
Provide a straight section with a length of at least 500 mm on
the main pipe side of the branch pipe. (Same for both liquid
side and gas side)
Outer dia. of copper pipe
Tightening torque
9.5 mm (diam.)
33 to 42 (3.3 to 4.2 kgf•m)
12.7 mm (diam.)
50 to 62 (5.0 to 6.2 kgf•m)
15.9 mm (diam.)
68 to 82 (6.8 to 8.2 kgf•m)
19.1 mm (diam.)
100 to 120 (10.0 to 12 kgf•m)
Half union or packed valve
Flare nut
Externally
threaded side
Internally threaded
side
Fix with wrench.
Tighten with torque wrench.
Cover
Piping valve
Tightened
Flare nut
Cap
Loosened
Valve at gas side
NO GOOD
Cover
Cap
Do not apply refrigerant oil to the flared surface.
The ends of the branch pipes
form a line perpendicular to
the ground.
Both the collecting
pipe and branch
pipes form a line
parallel to the ground.
Collection area
Collecting pipe
Branch pipe
Make sure that the pipes are
installed level after branching.
Inclined
The ends of the branch
pipes form a line
perpendicular to the ground.
Both the collecting
pipe and branch
pipes form a line
parallel to the ground.
Branch pipe
Liquid side
Gas side
NO GOOD
500 mm
or more
500 mm
or more
