Daikin Super Multi NX 3MXS-G Series Engineering Data page 271

Indoor Units
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
condensation 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.
Selection of Copper and Heat Insulation materials
When using commercial copper pipes and fittings, observe the following:
• Insulation material: Polyethylene foam
Heat transfer rate: 0.024 to 0.030Btu/hft°F
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
O.D. 3/8 inch (9.5mm)
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, more than 75% RH: 13/16in 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.
DRAIN PIPING WORK
Caution
Make sure all water is out before making the duct connection.
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: 25/32in; outer dimension: 1-1/32in).
• Keep the drain pipe short and sloping downwards at a gradient of at least
1/100 to prevent air pockets from forming.
266
O.D. 1/4 inch (6.4mm)
Minimum bend radius
1-3/16 inch (30mm) or more
Gas pipe thermal insulation Gas pipe thermal insulation Liquid pipe thermal insulation
I.D. 1/2 to 5/8 inch (15.9mm)
Thickness 0.393 inch (8mm) Min.
Gas pipe
Gas pipe
insulation
Finishing tape
EDUS121131
I.D. 3/8 inch (9.5mm)
Liquid pipe
Liquid pipe
insulation
Drain hose
Installation Manual