10. R
EFRIGERANT PIPING
10.1. Flaring the pipe end
To flare each pipe end, follow the procedure below:
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.
1 Cut exactly at right angles.
2 Remove burrs
3
Remove the flare nut from the stop valve and put the flare nut on
the pipe.
4
Flare the pipe. Set exactly at the position shown below.
Flare tool for R410A
(clutch type)
A
0~0.5 mm
5
Check that the flaring is properly made.
1 Flare's inner surface must be flaw-
free.
2 The pipe end must be evenly flared in
a perfect circle.
3 Make sure that the flare nut is fitted.
10.2. Connecting the refrigerant piping to the outdoor
unit
DANGER
Installation shall be done by an installer, the choice of
materials and installation shall comply with applicable
legislation. In Europe the EN378 is the application
standard that shall be used.
CAUTION
■
Do not use mineral oil on flared part.
Mineral oil getting into the system would reduce the
lifetime of the units.
■
Never use piping which has been used for previous
installations. Only use parts which are delivered with
the unit.
■
Do never install a drier to this R410A unit in order to
guarantee its lifetime. The drying material may
dissolve and damage the system.
■
Incomplete flaring may cause refrigerant gas leakage.
1
When connecting the flare nut, coat the flare inner surface with
ether oil or with ester oil and initially tighten 3 or 4 turns by hand
before tightening firmly.
RRLQ006~008BBV3
Outdoor unit for air to water heat pump
4PW68222-1 – 02.2011
1
A
Conventional flare tool
Clutch type
Wing nut type
(Ridgid-type)
(Imperial-type)
1.0~1.5 mm
1.5~2.0 mm
1
2
When loosening a flare nut, always use two wrenches together.
When connecting the piping, always use a spanner and torque
wrench together to tighten the flare nut to prevent nut cracking
and leaks.
1 Torque wrench
2 Spanner
3 Piping union
4 Flare nut
Flare nut
2
Ø6.4 mm (1/4")
Ø15.9 mm (5/8")
Valve cap
Ø6.4 mm (1/4")
Ø15.9 mm (5/8")
Service port cap tightening torque
10.3. Refrigerant piping work
Pipe handling guidelines
2
All pipe bends should be as gentle as possible. Use a pipe bender for
bending.
3
Bending radius should be 30 to 40 mm or larger.
Selection of copper and heat insulation materials
When using commercial copper pipes and fittings, observe the
following:
■
Insulation material: polyethylene foam
Heat transfer rate: 0.041 to 0.052 W/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.
■
Be sure to insulate both the gas and liquid piping and to provide
insulation dimensions as below.
Pipe size
Outer diameter
6.4 mm (1/4")
15.9 mm (5/8")
2
1
6
5
1 Gas pipe
2 Inter-unit wiring
3 Liquid pipe
4 Liquid pipe insulation
5 Finishing tape
6 Gas pipe insulation
■
Use separate thermal insulation pipes for gas and liquid
refrigerant pipes.
1
4
Flare nut tightening torque
15~17 N•m
63~75 N•m
Valve cap tightening torque
Gas pipe
21.6~27.4 N•m
44.1~53.9 N•m
10.8~14.7 N•m
Pipe insulation
Thickness
Inner diameter
0.8 mm
8-10 mm
1.0 mm
16-20 mm
3
4
Installation manual
2
3
Thickness
≥10 mm
≥13 mm
10