ENGLISH
REFRIGERANT PIPING
CAUTION
1) Use the flare nut fixed to the main unit. (To prevent cracking of the flare nut by aged deterioration.)
2) To prevent gas leakage, apply refrigeration oil only to the inner surface of the flare. (Use refrigeration oil for R32.)
3) Use torque wrenches when tightening the flare nuts to prevent damage to the flare nuts and gas leakage.
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.
Flare nut
[Tighten]
Torque wrench
Spanner
Do not apply refrigeration oil to the flare nut to
avoid tightening with excessive torque.
Pipe union
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 0.052W/mK (0.035 to 0.045kcal/(mh
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Choose heat insulation materials that will withstand this
temperature.
Wall
Rain
If no flare cap is available,
cover the flare mouth
with tape to keep dirt or
water out.
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
Gas pipe
Inter-unit wire
6.4 (1/4")
30mm or more
9.5 (3/8")
30mm or more
12.7 (1/2")
40mm or more
15.9 (5/8")
50mm or more
19.1 (3/4")
50mm or more
I.D. 8-10mm
I.D. 12-15mm
I.D. 14-16mm
I.D. 16-20mm
I.D. 20-24mm
Liquid pipe
0.8mm
(C1220T-O)
10mm Min.
Gas pipe insulation
Liquid pipe insulation
1.0mm
(C1220T-O)
Finishing tape
Drain hose
NOTICE
Do NOT exceed the unit’s maximum working pressure (see “Max. Allowable Pressure” on the unit name plate).
PURGING AIR AND CHECKING GAS LEAKAGE
• When piping work is completed, it is necessary to purge the air and check for gas leakage
WARNING
1) Do not mix any substance other than the specified refrigerant (R32) into the refrigeration cycle.
2) When refrigerant gas leaks occur, ventilate the room as soon and as much as possible.
3) R32, as well as other refrigerants, should always be recovered and never be released directly into the environment.
4) Use a vacuum pump for R32 exclusively. Using the same vacuum pump for different refrigerants may damage the vacuum
pump or the unit.
• If using additional refrigerant, perform air purging from the refrigerant pipes and indoor
unit using a vacuum pump, then charge additional refrigerant.
• Use a hexagonal wrench (4mm) to operate the stop valve rod.
• All refrigerant pipe joints should be tightened with a torque wrench at the specified
tightening torque.
Compound
pressure gauge
Gauge manifold
Pressure meter
valve
Charging hoses
Low-pressure
High
Valve
Liquid stop
pressure
caps valve
valve
Gas stop valve
Vacuum pump Service port
10
Be sure to place
a cap.
Pipe Size, mm (in)
Torque, Nm/(ft-lb)
6.4 (1/4")
18 (13.3)
9.5 (3/8")
42 (31.0)
12.7 (1/2")
55 (40.6)
15.9 (5/8")
65 (48.0)
19.1 (3/4")
78 (57.6)
