Refrigerant Piping - Daikin J-Series Engineeiring Data

Installation Manual
2.

Refrigerant piping

CAUTION
• Use the flare nut fixed to the main unit. (To prevent cracking of the flare nut by aged deterioration.)
• To prevent gas leakage, apply refrigeration oil only to the inner surface of the flare. (Use refrigeration oil for R410A.)
• Use torque wrenches when tightening the flare nuts to prevent damage to the flare nuts and gas leakage.
Align the centers of both flares and tighten the flare nuts 3 or 4 turns by hand. Then tighten them fully with the torque wrenches.
2-1. Caution on piping 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.
2-2. 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 (0.024 to 0.030Btu/fth°F (0.035 to
0.045kcal/mh°C))
Be sure to use insulation that is designed for use with HVAC Systems.
2) Be sure to insulate both the gas and liquid piping and to provide insulation
dimensions as below.
Gas side
O.D. 3/8 inch (9.5mm)
1-3/16 inch (30mm) or more
Thickness 0.031 inch (0.8mm) (C1220T-O)
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
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[Apply oil]
Do not apply refrigeration
oil to the outer surface.
Flare nut
Do not apply refrigeration
oil to the flare nut avoid
tightening with over torque.
Flare nut tightening torque
Gas side
3/8 inch (9.5mm)
24.1-29.4ft • lbf
(32.7-39.9N • m)
Liquid side
O.D. 1/4 inch (6.4mm)
Minimum bend radius
[Tighten]
Apply refrigeration oil to
Torque wrench
the inner surface of the
flare.
Spanner
Piping union
Flare nut
Liquid side
1/4 inch (6.4mm)
10.4-12.7ft • lbf
(14.2-17.2N • m)
Rain
Gas pipe thermal Liquid pipe thermal
insulation insulation
I.D. 0.427-0.590 inch I.D. 0.315-0.393 inch
(12-15mm) (8-10mm)
Thickness 0.393 inch (10mm) Min.
Wall
Be sure to
place a cap.
If no flare cap is
available, cover
the flare mouth
with tape to keep
dirt or water out.
Inter-unit wiring
Gas pipe
Liquid pipe
Gas pipe Liquid pipe
insulation insulation
Finishing tape
Drain hose
11
Room Air Conditioners J-Series
EDUS041011