Refrigerant Piping Work - Daikin M08B128 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 lifetime of the units.
3) Never use piping which has been used for previous installations. Only use parts which are delivered
with the unit.
4) Never install a drier to this R410A unit in order to guarantee it's lifetime.
5) The drying material may dissolve and damage the system.
6) Incomplete 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
Do not apply refrigeration oil to the flare
nut to avoid tightening with over torque.
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 (0.024-0.030Btu/fth˚F (0.035-0.045kcal/mh˚C))
Refrigerant gas pipe's surface temperature reaches 230˚F (110˚C) 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.
Gas side
O.D. 5/8 inch (15.9mm)
1-15/16 inch (50mm) or more
Thickness 0.039 inch (1mm) (C1220T-O)
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.

Refrigerant Piping Work

[Apply oil]
Apply refrigeration oil to the
inner surface of the flare.
Liquid side
O.D. 3/8inch (9.5mm)
Minimum bend radius
1-3/16 inch (30mm) or more
Thickness 0.031 inch (0.8mm) (C1220T-O)
(Cut exactly at
right angles.)
Set exactly at the position shown below.
A Flare tool for R410A
A 0-0.020 inch (0-0.5mm)
Die
[Tighten]
Torque wrench
Spanner
Piping union
Flare nut
Gas pipe thermal insulation
I.D. 0.630-0.787 inch (16-20mm)
Remove burrs
Flaring
Conventional flare tool
Clutch-type Clutch-type (Rigid-type)
0.039-0.059 inch (1.0-1.5mm)
Check
Flare's inner
surface must
be flaw-free.
Flare nut tightening torque
Gas side
5/8 inch (15.9mm) 3/8 inch (9.5mm)
45.6-55.6ft lbf
(61.8-75.4N m) (32.7-39.9N m)
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.
Gas pipe
Gas pipe
insulation
Finishing tape
Liquid pipe thermal insulation
I.D. 0.472-0.591 inch (12-15mm)
Thickness 0.393 inch (10mm) Min.
Wing-nut type (Imperial-type)
0.059-0.079 inch (1.5-2.0mm)
The pipe end must
be evenly flared in
a perfect circle.
Make sure that the
flare nut is fitted.
Liquid side
24.1-29.4ft lbf
Wall
Inter-unit wiring
Liquid pipe
Liquid pipe
insulation
Drain hose