Fujitsu AUYG18LVLB, Design & Technical Manual

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Additional charging amount for Triple type
L1 L4
L3
L2
Pre-charge length < L1 + L2 + L3 + L4
The additional charging amount will be calculated as follows.
• A: Piping length (m) of liquid pipe with outside diameter of 12.70 mm (1/2 in)
• B: Piping length (m) of liquid pipe with outside diameter of 9.52 mm (3/8 in)
• C: Piping length (m) of liquid pipe with outside diameter of 6.35 mm (1/4 in)
• Additional charging amount (g) = (A × 110) + (B × 50) + (C × 30) - 3,300
NOTE: Do not remove refrigerant, even if the additional amount calculated is negative.
Example:
Indoor unit
30,000 Btu
Indoor unit
30,000 Btu
Indoor unit
30,000 Btu
Outdoor unit
90,000 Btu
Liquid pipe (mm)
Gas pipe (mm)
9.52
15.88
L2: 5 m
Liquid pipe (mm)
Gas pipe (mm)
9.52
15.88
L3: 5 m
Liquid pipe (mm)
Gas pipe (mm)
12.70
25.40
L1: 10 m
Liquid pipe (mm)
Gas pipe (mm)
9.52
15.88
L4: 5 m
Liquid pipe diameter (mm) Piping length (m) Coefficient
12.70 10 A = 10
9.52 15 B = 15
6.35 0 C = 0
Applying the formula,
(10 × 110) + (15 × 50) + (0 × 30) - 3,300 = -1,450
The calculated value is negative. Do not add or remove any refrigerant.
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2-5. Additional charge calculation 2. Pipe design
SYSTEM DESIGN SYSTEM DESIGN