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ENGLISH
The amount of Refrigerant
The calculation of the additional charge should take into account the
length of pipe and CF(correction Factor) value of indoor unit.
Total liquid pipe : Ø25.4 mm (1.0 inch)
Additional charge(kg)
Total liquid pipe : Ø22.2 mm (7/8 inch)
Total liquid pipe : Ø19.05 mm (3/4 inch)
Total liquid pipe : Ø15.88 mm (5/8 inch)
Total liquid pipe : Ø12.7 mm (1/2 inch)
Total liquid pipe : Ø9.52 mm (3/8 inch)
Total liquid pipe : Ø6.35 mm (1/4 inch)
CF value of indoor unit
=
+
+
+
+
+
+
× 0.480 kg/m (0.323 lbs/ft)
× 0.354 kg/m (0.238 lbs/ft)
× 0.266 kg/m (0.179 lbs/ft)
× 0.173 kg/m (0.116 lbs/ft)
× 0.118 kg/m (0.079 lbs/ft)
× 0.061 kg/m (0.041 lbs/ft)
× 0.022 kg/m (0.015 lbs/ft)
Amount refrigerant of Indoor units
Example) 4Way Ceiling Cassette 14.5kW -1ea, Ceiling concealed
Duct 7.3kW-2ea,
Wall Mounted 2.3kW-4ea
CF = [0.64 kg (1.411 lbs)×1EA] + [0.26 kg (0.573
lbs)×2EA] + [0.26 kg (0.529 lbs)×4EA]
= 2.12 kg (4.67 lbs)
WARNING
• Regulation for refrigerant leakage
: the amount of refrigerant leakage should satisfy the following
equation for human safety.
If the above equation can not be satisfied, then follow the follow-
ing steps.
• Selection of air conditioning system: select one of the next
- Installation of effective opening part
- Reconfirmation of Outdoor Unit capacity and piping length
- Reduction of the amount of refrigerant
- Installation of 2 or more security device (alarm for gas leakage)
• Change Indoor Unit type
: installation position should be over 2 m (6.6 ft) from the floor (Wall
mounted type
’
Cassette type)
• Adoption of ventilation system
: choose ordinary ventilation system or building ventilation sys-
tem
• Limitation in piping work
: Prepare for earthquake and thermal stress
!
Volume of the room at which Indoor Unit of
the least capacity is installed
Total amount of refrigerant in the system
≤
0.44 kg/m
3
(0.028 lbs/ft
3
)
Attach the additional refrigerant table of IDU.
Bad example
• Do not insulate gas or low pressure pipe and liquid or highpres-
sure pipe together.
• Be sure to fully insulate connecting portion.
Ⓐ
These parts are not insulated.
Ⓐ
Liquid pipe
Ⓑ
Gas pipe
ⓒ
Power lines
ⓓ
Finishing tape
ⓔ
Insulating material
ⓕ
Communication lines
A
C
D
E
B
F
A
Be sure to give insulation work to refrigerant piping by covering liquid
pipe and gas pipe separately with enough thickness heat-resistant poly-
ethylene, so that no gap is observed in the joint between indoor unit
and insulating material, and insulating materials themselves. When in-
sulation work is insufficient, there is a possibility of condensation drip,
etc. Pay special attention to insulation work to ceiling plenum.
Ⓐ
Heat insulation material
Ⓑ
Pipe
Ⓒ
Outer covering(Wind the connection part and cutting part of heat in-
sulation material with a finishing tape.)
Heat insulation
material
Ad Heat - resistant poly-
ethylene foam + Adhesive tape
Outer
covering
Indoor
Vinyl tape
Floor ex-
posed
Water-proof hemp cloth +
Bronze asphalt
Outdoor
Water-proof hemp cloth +
Zinc plate + Oily paint
NOTE
!
When using polyethylene cover as covering material, asphalt roof-
ing shall not be required.
Thermal insulation of refrigerant piping
Good example
Ⓐ
Liquid pipe
Ⓑ
Gas pipe
ⓒ
Power lines
ⓓ
Insulating material
ⓔ
Communication lines
Communication lines
Separation
Power lines
E
D
D
B
A
C
1,MFL67221438,영영 2018. 10. 4. 영영 11:29 Page 20
