Installation manual

7 ■English
Outdoor Unit Installation
6.
Refilling The Refrigerant
Check the type of refrigerant to be used on the machine nameplate.
Precautions when adding R410A
Fill from the liquid pipe in liquid form.
It is a mixed refrigerant, so adding it in gas form may cause the refrigerant composition to change, preventing normal operation.
1) Before filling, check whether the cylinder has a siphon attached or not. (It should have something like “liquid filling siphon
attached” displayed on it.)
• Be sure to use the R410A tools to ensure pressure and to prevent foreign objects entering.
7.
Refrigerant Piping Work
7-1 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 40mm or larger.)
7-2 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 0.045kcal/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 dimen-
sions as below.
• Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
Gas side Liquid side
Gas pipe thermal
insulation
Liquid pipe
thermal
insulation
50/60 class 71 class
50/60/71
class
50/60
class
71 class
50/60/71
class
O.D.
12.7mm
O.D.
15.9mm
O.D. 6.4mm
I.D.
14-16mm
I.D.
16-20mm
I.D. 8-10mm
Thickness
0.8mm
Thickness
1.0mm
Thickness
0.8mm
Thickness 10mm Min.
Filling a cylinder with an attached siphon
Stand the cylinder upright when
filling.
There is a siphon pipe inside, so the
cylinder need not be upside-down to
fill with liquid.
Filling other cylinders
Turn the cylinder upside-down
when filling.
Wall
If no flare cap is
available, cover
the flare mouth
with tape to keep
dirt or water out.
Be sure to
place a cap.
Rain
Gas pipe
Liquid pipe
Gas pipe
insulation
Liquid pipe
insulation
Finishing tape
Drain hose
Inter-unit wiring
01_EN_3P159684-2F.fm Page 7 Wednesday, December 7, 2005 3:18 PM