5.
Charging with Refrigerant
• If the total length of piping for all rooms exceeds 20m, additionally charge with (R410A) 20 g of refrigerant for each addi-
tional meter of piping.
When extra refrigerant is added, write down the total length of the piping and the amount added on the nameplate for
recording how much refrigerant has been added on the back of the service lid on the outdoor unit.
Caution
1) Even though the shut-off valve is fully closed, the refrigerant may slowly leak out; do not leave the flare nut removed for a long
period of time.
2) Do not overfill with refrigerant. This will break the compressor.
6.
Refrigerant Piping Work
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. (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:
1) Insulation material: Polyethylene foam
Heat transfer rate: 0.041 to 0.052kW/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 dimen-
sions as below.
Gas pipe
O.D.: 9.5mm / Thickness:0.8mm
Liquid pipe
O.D.: 6.4mm / Thickness:0.8mm
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
7.
Flaring the Pipe End
1) Cut the pipe end with a pipe cutter.
2) Remove burrs with the cut surface facing down-
ward 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.
4) Only use parts which are delivered with the unit.
5) Do never install a drier to this R410A unit in order to guarantee its lifetime. The drying material may dissolve and damage the
system.
6) Incomplete flaring may cause refrigerant gas leakage.
IEnglish
Gas pipe insulation
I.D.: 12 – 15mm / Thickness:13mm min.
Liquid pipe insulation
I.D.: 8 – 10mm / Thickness:10mm min.
Set exactly at the position shown below.
A
Die
Be sure to
place a cap.
Rain
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
(Cut exactly at
right angles.)
Remove burrs
Flaring
Flare tool for R410A
Conventional flare tool
Clutch-type
Clutch-type (Rigid-type)
A
0 ~ 0.5 mm
1.0 ~ 1.5 mm
Flare's inner
surface must
be flaw-free.
Wall
Inter-unit wiring
Liquid pipe
Liquid pipe
insulation
Drain hose
Wing-nut type (Imperial-type)
1.5 ~ 2.0 mm
Check
The pipe end must
be evenly flared in
a perfect circle.
Make sure that the
flare nut is fitted.
8