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4. REFRIGERANT PIPING WORK
GB-12
Check if the height difference between indoor unit & outdoor unit and the total length of refrigerant pipe
meet system requirement.
Refrigerant piping work follows the indoor unit and outdoor unit installation, connect the pipe at the indoor
side first, then the outdoor side.
Always keep ends of tubing sealed by placing a cap or covering with tape during installation and do NOT
remove them until you are ready to connect the piping.
Be sure to insulate any field piping all the way to the piping connection inside the unit. Any exposed piping
may cause condensation or burns if touched.
CAUTION
4.1 FLARING
90
Oblique Rough Burr
Outside diameter
A(mm)
Max
8.7
Φ
6.35mm
Φ
9.52mm
Φ
12.7mm
Φ
15.88mm
Φ
19.05mm
12.4
15.8
19.0
23.3
8.3
12.0
15.4
18.6
22.9
Min
R0.4~0.8
45 °±
2
90 °
± 4
A
In case of needing brazing, work with Nitrogen gas blowing.
Improper torque will cause flare damage or gas leaks.
CAUTION
Torque
Tubing size
18 ~ 20 N.m
25 ~ 26 N.m
35 ~ 36 N.m
45 ~ 47 N.m
65 ~ 67 N.m
Φ
6.35mm
Φ
9.52mm
Φ
12.7mm
Φ
15.88mm
Φ
19.05mm
Use separate thermal insulation pipes for gas &
liquid pipes.
The thickness above is a standard of the indoor
temperature of 27°C and humidity of 80%. If installing
in an unfavorable conditions such as near bath-
rooms, kitchens, and other similar locations,
reinforce the insulation.
Insulation’s heat-resistance temperature should be
more than 120°C.
Use the adhesives on the connection part of insula-
tion to prevent moisture from entering.
Repair and cover any possible cracks in the insulation
specially check the bent part or hanger of pipe.
4.1.1 Using a pipe cutter to cut the pipe to the requested
length. Ensure that the cut edge remains at 90° with
the side of the pipe.
4.1.2 Use a reamer to remove burrs with the cut surface
downward so that the chips do not enter the pipe.
4.1.3 Carry out flaring work using flaring tools as below.
4.1.4 Check if the flaring is properly made. See incorrectly
flared pipes sample below.
4.2 PIPING WORK
4.2.1 Align the center to tighten the flare nut and
finish connection using two wrenches.
Flare nut
Wrench
Torque wrench
4.2.2 Select the appropriate insulation material for
refrigerant pipe. (Min. 10mm, thermal insulating
foam C)
Inclined Damaged
Surface
Cracked
Uneven
Thickness
NOTE
Tools required for flaring are pipe cutter, reamer,
flaring tool and pipe holder.
For R32 refrigerant models, the pipe connection
points must be placed outside of room.
GB
Summary of Contents for 38QUS012
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