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English
Refrigerant Piping Work
CAUTION
Be sure to insulate any field piping all the way to the piping connection inside the unit. Any exposed piping may cause condensa
-
tion or burns if touched.
Cautions on Pipe Handling
• Protect the open end of the pipe against dust and moisture.
(Tighten both edges with clamp.)
• All pipe bends should be as gentle as possible. Use a pipe bender for bending.
(See the minimum bend radius in the table below.)
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
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 0.052W/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.
• 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. 3/8 inch
(9.5mm)
O.D. 1/2 inch
(12.7mm)
O.D. 5/8 inch
(15.9mm)
O.D. 1/4 inch
(6.4mm)
I.D. 15/32-19/32
inch (12-15mm)
I.D. 9/16-5/8
inch (14-16mm)
I.D. 5/8-25/32
inch (16-20mm)
I.D. 5/16-13/32
inch (8-10mm)
Minimum bend radius
Thickness 13/32 inch (10mm) Min.
1-3/16 inch
(30mm) or more
1-9/16 inch
(40mm) or more
1-15/16 inch
(50mm) or more
1-3/16 inch
(30mm) or more
Thickness 0.031 inch (0.8mm)
(C1220T-O)
Thickness 0.039
inch (1.0mm)
(C1220T-O)
Thickness 0.031
inch (0.8mm)
(C1220T-O)
Also, when subject to high humidity, heat insulation of the refrigerant piping (the unit piping and
branch piping) must be further reinforced.
Reinforce the insulation when installing the unit near bathrooms, kitchens, and other similar locations.
Refer to the following:
• 86°F (30°C), more than 75% RH: 13/16 inch (20mm) Min. in thickness
If the insulation is not sufficient, condensation may form on the surface of the insulation.
• Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
Gas pipe
Liquid pipe
Gas pipe
insulation
Liquid pipe
insulation
Finishing tape
Drain hose
Drain Piping Work
CAUTION
Make sure all water is out before making the duct connection.
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Install the drain piping.
• Make sure the drain works properly.
• The diameter of the drain pipe should be greater than or equal to the diameter of
the connecting pipe (vinyl tube; pipe size: 25/32 inch (20mm); outer dimension:
1-1/32 inch (26mm)).
Drain pipe connection hole
Refrigerant pipes
Connect the drain pipe after
removing the rubber cap and
insulation tubing attached to
the connection hole.
• Keep the drain pipe short and sloping downwards at a gradient of at least 1/100
to prevent air pockets from forming.
OK
Wrong
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