Refrigerant Piping Work; Flaring; Piping Work; Refrigerant Pipe - CIAT 42HV09JS8C Manuel D'installation

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.
When the outdoor unit is the top position and the difference of level is over 10m, it is recommended that set
a oil return bend every 5~8m in the gas pipe. The radius of oil reture bend should be over than 10cm.

4.1 FLARING

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.
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 Rough Burr
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
90 ° ± 4
Max Min
Φ6.35mm
8.7 8.3
A
Φ9.52mm
12.4 12.0
Φ12.7mm
15.8 15.4
Φ15.88mm
19.0 18.6
Φ19.05mm
23.3 22.9
4.1.4 Check if the flaring is properly made. See
incorrectly flared pipes sample below.
Inclined Damaged Surface Cracked Uneven Thickness
CAUTION
In case of needing brazing, work with Nitrogen gas blowing.
Improper torque will cause flare damage or gas leaks.
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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 Torque
Φ6.35mm
18 ~ 20 N.m
Φ9.52mm
25 ~ 26 N.m
Φ12.7mm
35 ~ 36 N.m
Φ15.88mm
45 ~ 47 N.m
Φ19.05mm 65 ~ 67 N.m
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 install-
R0.4~0.8
ing 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 insula-
tion, specially check the bent part or hanger of
pipe.
4. REFRIGERANT PIPING WORK

4.3 REFRIGERANT PIPE

Minimum length
Refrigerant to reduce abnormal Chargeless length
vibration & noise Liquid side:φ6.35mm
R410A
3m 5m
R32
* Please use tools for R410A/R32 system respectively.
NOTE
The refrigerant should be charged from the service port on the outdoor unit's low pressure valve.
Extended pipe length will affect the capacity and energy efficiency of the unit.
The nominal efficiency is tested based on the pipe length of 5 meter.
When the pipe length is over 5m, the additional refrigerant should be added according to the pipe length.
The max. pipe length is recommended as below.
Inverter Model Capacity(kW)
Max. pipe length(m)
7k/9k/12k
25
18k 30
24k 40
* Please use tools for R410A/R32 system respectively.

4.4 AIR EVACUATION

Connect the charge hose from the manifold gauge to the service port of the gas side packed valve.
Connect the charge hose to the port of the vacuum pump.
Fully open the handle Lo of manifold gauge.
Operate the vacuum pump to evacuate air from the system until -76cmHg.
Close the handle Lo of manifold gauge.
Fully open the valve stem of the packed valves.
Remove the charging hose form the service port.
Securely tighten caps of packed valve.
Manifold valve
Compound gauge
-76 cmHg
Handle Lo
Charge hose

4.5 LEAKAGE TEST

After the piping work is finished, make sure to check the connection part of each refrigerant pipe and confirm
that there is no gas leak by applying soapy water to them or by using a leak detector specific for HFC refrigerants.
Refer below picture for illustration.
Check-point of indoor unit
Check-point of outdoor unit
A: Low pressure stop valve
C & D: Indoor unit flare nuts
Additional charge per meter
Liquid side:φ9.52mm
15g 30g
12g 24g
Max. height difference(m)
10
20
20
Pressure meter
Handle Hi
Charge hose
Vacuum pump
Packed valve
D
B C
A
B: High pressure stop valve
12