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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 gas 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.)
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.
• Be sure to use the R410A tools to ensure pressure and to prevent foreign objects entering.
7.
Refrigerant piping work
7-1 Caution 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))
Be sure to use insulation that is designed for use with HVAC Systems.
2) Be sure to insulate both the gas and liquid piping and to provide insulation
dimensions as below.
Gas side
Liquid side
Gas pipe thermal
insulation
Liquid pipe thermal
insulation
O.D. 5/8 inch
(15.9mm)
O.D. 3/8 inch
(9.5mm)
I.D. 5/8-25/32 inch
(16-20mm)
I.D. 15/32-19/32 inch
(12-15mm)
Minimum bend radius
Thickness 13/32 inch (10mm) Min.
1-15/16 inch (50mm)
or more
1-3/16 inch (30mm)
or more
Thickness
0.039 inch (1.0mm)
(C1220T-O)
Thickness
0.031 inch (0.8mm)
(C1220T-O)
• Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
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 wire
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