Refrigerant Piping Work; Flaring; Piping Work - Carrier 42QTD024DS-Serie Installationshandbuch

4. REFRIGERANT PIPING WORK

CAUTION
C
heck if the height difference between indoor unit & outdoor unit and the total length of refrigerant pipe
meet system requirement.
R
efrigerant piping work follows the indoor unit and outdoor unit installation, connect the pipe at the indoor
side first, then the outdoor side.
A
lways 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.
B
e 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.

4.1 FLARING

NOTE
Tools required for flaring are pipe cutter, reamer, flaring
tool and pipe holder.
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.
Oblique
90
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.
A(mm)
Outside diameter
Max
Φ6.35mm 8.7
12.4
Φ9.52mm
Φ12.7mm
15.8
Φ15.88mm 19.0
Φ19.05mm 23.3
4.1.4 Check if the flaring is properly made. See incorrectly
flared pipes sample below.
Inclined Damaged Surface
CAUTION
In case of needing brazing, work with Nitrogen gas blowing.
Improper torque will cause flare damage or gas leaks.
GB-12
Rough Burr
Min
90 ° ± 4
8.3
A
12.0
15.4
R0.4~0.8
18.6
22.9
Cracked Uneven Thickness

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
Tubing size
Φ6.35mm
Φ9.52mm
Φ12.7mm
Φ15.88mm
Φ19.05mm
4.2.2 Select the appropriate insulation material for refrigerant
pipe. (Min. 10mm, thermal insulating foam C)
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 bathrooms, 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 insulation to
prevent moisture from entering.
Repair and cover any possible cracks in the insulation specially
check the bent part or hanger of pipe.
Torque
18 ~ 20 N.m
25 ~ 26 N.m
35 ~ 36 N.m
45 ~ 47 N.m
65 ~ 67 N.m