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REFRIGERANT PIPING
1) Use the flare nut fixed to the main unit. (This is to prevent the flare nut from cracking as a result of deterioration over time.)
2) To prevent gas leakage, apply refrigeration oil only to the inner surface of the flare. (Use refrigeration oil for R410A.)
3) Use torque wrenches when tightening the flare nuts to prevent damage to the flare nuts and gas leakage.
CAUTION
Align the centres of both flares and tighten the flare nuts 3 or 4 turns by hand. Then tighten them fully with the torque
wrenches.
[Apply oil]
Apply refrigeration oil to the inner surface of the flare.
Do not apply refrigeration oil to the outer surface.
Do not apply refrigeration oil to the flare nut to
avoid tightening with excessive torque.
Flare nut
1. Cautions on pipe handling
1) Protect the open end of the pipe against dust and moisture.
2) All pipe bends should be as gentle as possible.
Use a pipe bender for bending.
2. Selection of copper and heat insulation materials
When using commercial copper pipes and fittings, observe the following:
1) Insulation material: Polyethylene foam
Heat transfer rate: 0.041 to 0.052 W/mK (0.035 to 0.045 kcal/(mh •
˚
C)
Refrigerant gas pipe’s surface temperature reaches 110
˚
C (230°F) max.
Choose heat insulation materials that will withstand this temperature.
2) Be sure to insulate both the gas and liquid piping and to provide insulation dimensions as below.
Piping size,
mm (in)
Minimum bend
radius
Piping
thickness
Thermal insulation
size
Thermal insulation
thickness
6.40 (1/4") 1-3/16" (30mm) or more
1/32" (0.8mm)
(C1220T-O)
I.D. 5/16" (8mm) - 13/32" (10mm)
13/32" (10mm) Min.
9.52 (3/8") 1-3/16" (30mm) or more
I.D. 15/32" (12mm) - 9/16" (15mm)
12.70 (1/2") 1-9/16" (40mm) or more
I.D. 9/16" (14mm) - 10/16" (16mm)
15.88 (5/8") 1-15/16" (50mm) or more 5/128" (1.0mm)
(C1220T-O)
I.D. 10/16" (16mm) - 25/32" (20mm)
19.05 (3/4") 1-15/16" (50mm) or more
I.D. 25/32" (20mm) - 15/16" (24mm)
3) Be sure to insulate both the gas and liquid piping and to provide insulation dimensions as below.
NOTICE
Do NOT exceed the unit
ʼ
s maximum working pressure (see “Max. Allowable Pressure” on the unit name plate).
Inter-unit wire
Drain hose
Liquid pipe
insulation
Gas pipe
insulation
Finishing tape
Gas pipe
Liquid pipe
[Tighten]
Torque wrench
Spanner
Pipe union
Flare nut
Pipe Size, mm (in) Torque, Nm/(ft-lb)
6.40 (1/4")
18 (13.3)
9.52 (3/8")
42 (31.0)
12.70 (1/2")
55 (40.6)
15.88 (5/8")
65 (48.0)
19.05 (3/4")
78 (57.6)
Wall
Rain
Be sure to place
a cap.
If no flare cap is
available, cover the flare
mouth with tape to keep
dirt or water out.
SPECIAL PRECAUTIONS WHEN DEALING WITH R410A UNIT
R410A is a new HFC refrigerant which does not damage the ozone
layer. The working pressure of this new refrigerant is 1.6 times
higher than conventional refrigerant (R22), thus proper installation/
servicing is essential.
• Never use refrigerant other than R410A in an air conditioner
which is designed to operate with R410A.
• POE or PVE oil is used as lubricant for R410A compressor,
which is different from the mineral oil used for R22 compressor.
During installation or servicing, extra precaution must be taken
not to expose the R410A system too long to moist air. Residual
POE or PVE oil in the piping and components can absorb
moisture from the air.
• To prevent mischarging, the diameter of the service port on the
flare valve is different from that of R22.
• Use tools and materials exclusively for refrigerant R410A.
Tools exclusively for R410A are manifold valve, charging hose,
pressure gauge, gas leak detector, flare tools, torque wrench,
vacuum pump and refrigerant cylinder.
• As an R410A air conditioner incurs higher pressure than R22
units, it is essential to choose the copper pipes correctly.
• If the refrigerant gas leakage occurs during installation/
servicing, be sure to ventilate fully. If the refrigerant gas comes
into contact with fire, a poisonous gas may occur.
• When installing or removing an air conditioner, do not allow air
or moisture to remain in the refrigerant cycle.
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