Refrigerant Piping Work - Daikin FTXR28EV1B Installation Manual

Refrigerant Piping Work

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) Do never install a drier to this R410A unit in order to guarantee its lifetime.
5) The drying material may dissolve and damage the system.
6) Incomplete flaring may cause refrigerant gas leakage.
2.
Refrigerant piping.
1) 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.
• Use torque wrenches when tightening the flare nuts to
prevent damage to the flare nuts and escaping gas.
2) To prevent gas leakage, apply refrigeration oil on both
inner and outer surfaces of the flare. (Use refrigeration
oil for R410A.)
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.
(Bending radius should be 30 to 40mm or larger.)
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 (0.035 to 0.045 kcal/(mh•°C))
Refrigerant gas pipe's surface temperature reaches 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. 9.5mm
Thickness 0.8mm
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
13
Set exactly at the position shown below.
Gas pipe thermal
Liquid side
insulation
O.D. 6.4mm I.D. 12-15mm
Thickness 10mm Min.
(Cut exactly at
right angles.)
Flaring
A
Flare tool for R410A
Clutch-type
Die A 0-0.5mm
Flare nut tightening torque
Gas side
3/8 inch
32.7-39.9N m
(330-407kgf cm)
Coat here with refrigeration oil
Rain
Gas pipe
insulation
Liquid pipe insulation
Liquid pipe thermal
insulation
I.D. 8-10mm
Remove burrs
Conventional flare tool
Clutch-type (Rigid-type) Wing-nut type (Imperial-type)
1.0-1.5mm 1.5-2.0mm
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.
Liquid side
1/4 inch
14.2-17.2N m
(144-175kgf cm)
Torque wrench
Spanner
Piping union
Flare nut
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.
Finishing tape
Inter-unit wiring
Gas pipe
Drain hose
Humidifying
hose
Liquid pipe
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