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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.
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 (0.024 to 0.030Btu/fth°F (0.035 to 0.045kcal/mh°C))
Refrigerant gas pipe’s surface temperature reaches 230°F (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.
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
Gas side
Liquid side
Gas pipe
thermal insulation
Liquid pipe
thermal insulation
O.D. 3/8 inch
(9.5mm)
O.D. 1/4 inch
(6.4mm)
I.D. 0.472-0.591 inch
(12-15mm)
I.D. 0.315-0.393 inch
(8-10mm)
Minimum bend radius
Thickness 0.393 inch (10mm) Min.
1-3/16 inch (30mm) or more
Thickness 0.031 inch (0.8mm) (C1220T-O)
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_3P253189-4E.fm Page 8 Monday, September 6, 2010 4:20 PM
