Daikin CTXU25G2V1B Service Manual page 67

Installation Manual
Refrigerant Piping Work
Precautions for Laying Refrigerant Piping
• 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.
• 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˚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.
40 or 50class
O.D. 9.5mm
30mm or more
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
• 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.
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Gas side
Liquid side
50 class
O.D. 12.7mm O.D. 6.4mm
Minimum bend radius
40mm or more 30mm or more
Thickness 0.8mm (C1220T-O)
Rain
Liquid pipe insulation
Gas pipe thermal insulation
40 class 50 class
I.D. 12-15mm
Thickness 13mm Min.
(Cut exactly at
right angles.)
Flaring
Set exactly at the position shown below.
A Flare tool for R410A
Clutch-type
Die A 0-0.5mm
SiBE12-908
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
Gas pipe
insulation
Humidifying
hose
Liquid pipe
Liquid pipe
thermal insulation
I.D. 8-10mm
Thickness
10mm Min.
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.
Installation / Operation Manual