Refrigerant Piping Work - Daikin H-Series Engineeiring Data

Installation Manual
1.
Flaring the pipe end.
1) Cut the pipe end with a pipe cutter.
2) Remove burrs with the cut surface facing
downward so that the chips do not enter the pipe.
3) Put the flare nut on the pipe.
4) Flare the pipe.
5) Check that the flaring is properly made.
WARNING
1) Do not use mineral oil on flared part.
2) Prevent mineral oil from getting into the system as this would reduce the unit life.
3) Never use piping which has been used for previous installations. Only use parts which are provided with the unit.
4) Never install a refrigerant drier to this unit.
5) The drying material may dissolve and damage the system.
6) Incomplete or improper flaring may cause refrigerant gas leakage.
2.
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 R410A.)
3) 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.
Do not apply refrigeration
oil to the outer surface.
Flare nut
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 0.052 W/mK (0.024 to 0.030 Btu/fth°F (0.035 to 0.045 kcal/mh°C))
Choose heat insulation materials that are designed for HVAC use.
2) Be sure to insulate both the gas and liquid piping and to provide
insulation dimensions as below.
O.D. 3/8 inch (9.5mm)
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
36

Refrigerant Piping Work

[Apply oil]
Apply refrigeration
oil to the inner
surface of the flare.
Spanner
Piping union
Do not apply refrigeration
oil to the flare nut avoid
tightening with over torque.
Gas side Liquid side
O.D. 1/4 inch (6.4mm)
Minimum bend radius
1-3/16 inch (30mm) or more
Thickness 0.031 inch (0.8mm) (C1220T-O)
(Cut exactly at
right angles.) Remove burrs
Set exactly at the position shown below.
A
Flare tool for R410A
Clutch-type
Die A 0 - 0.020 inch (0 - 0.5mm)
[Tighten]
Torque wrench
Flare nut tightening torque
Gas side
3/8 inch
24.1 - 29.4ft • Ibf
(32.7 - 39.9N • m)
Flare nut
Rain
Gas pipe thermal insulation
I.D. 0.427 - 0.590 inch (12 - 15mm)
Thickness 0.393 inch (8mm) Min.
EDUS04-904
Check
The pipe end must
Flare's inner
be evenly flared in
surface must
a perfect circle.
be flaw-free.
Make sure that the
flare nut is fitted.
Flaring
Conventional flare tool
Clutch-type (Rigid-type) Wing-nut type (Imperial-type)
0.039 - 0.059 inch (1.0 - 1.5mm) 0.059 - 0.079 inch (1.5 - 2.0mm)
Liquid side
1/4 inch
10.4 - 12.7ft • Ibf
(14.2 - 17.2N • m)
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
Liquid pipe thermal insulation
I.D. 0.315 - 0.393 inch (8 - 10mm)
Room Air Conditioners H-Series