Tubing Size; Straight Equivalent Length Of Joints; Additional Refrigerant Charge; Refrigerant Charge Amount - Panasonic U-36LE1U6 Installation Instructions Manual

1-5. Tubing Size

Table 1-2 Main Tubing Size (LA)
BTU/h (kW) 38,200 (11.2)
System horsepower 4
Gas tubing ø5/8" (ø15.88)
Liquid tubing ø3/8" (ø9.52)
Note: If the system consists of only one indoor unit with an outdoor 6HP (Type 52), the main tube of the unit (LA) should be ø19.05.
Convert ø19.05 to ø15.88 using a reducer (field supply) close to the indoor unit and then make the connection.
Table 1-3 Main Tubing Size After Distribution (LB, LC...)
Below BTU/h
Total capacity
after distribution
Over BTU/h
Gas tubing
Tubing size
Liquid tubing
Note: In case the total capacity of connected indoor units exceeds the total capacity of the outdoor units, select the main
tubing size for the total capacity of the outdoor units.
Table 1-4 Indoor Unit Tubing Connection (
Indoor unit type 7
Gas tubing
Liquid tubing

1-6. Straight Equivalent Length of Joints

Design the tubing system by referring to the following table for the straight equivalent length of joints.
Table 1-5 Straight Equivalent Length of Joints
Gas tubing size (in. (mm))
90° elbow
45° elbow
U-shape tube bend (R2-3/8" – 4" (60 – 100))
Trap bend
Y-branch distribution joint
Ball valve for service
Table 1-6 Required Copper Tubing Dimensions
Material
Outer diameter
Copper tube
Wall thickness

1-7. Additional Refrigerant Charge

Additional refrigerant charge amount is calculated from the liquid tubing total length as follows.
Table 1-7 Amount of Refrigerant Charge Per ft., According to Liquid Tubing Size
Liquid tubing size Amount of refrigerant
(in. (mm))
ø1/4" (ø6.35)
ø3/8" (ø9.52)
52,900 (15.5)
6
ø3/4" (ø19.05)
Unit: in. (mm)
24,200 (2.5 hp) 38,200 (4 hp) 47,800 (5 hp)
– 24,200 (2.5 hp)
ø1/2" (ø12.7) ø5/8" (ø15.88)
ø3/8" (ø9.52) ø3/8" (ø9.52)
, ...
1 2 n–1
9 12 15 18
o1/2" (o12.7)
o1/4" (o6.35)
1/2" (12.7) 5/8" (15.88)
1 1.1
0.8 0.9
3 3.4
7.5 9.2
Equivalent length conversion not needed.
Equivalent length conversion not needed.
1/4 (6.35) 3/8 (9.52)
1/32 (0.8) 1/32 (0.8)
Required amount of charge = (Amount of refrigerant
charge per ft. of each size of liquid tube × its tube
charge (oz/ft.)
length) + (...) + (...)
0.279
0.602
*Always charge accurately using a scale for weighing.
8
52,900 (6 hp)
ø3/4" (ø19.05)
Unit: in. (mm)
hp = horsepower
)
19 24 36
o5/8" (o15.88)
o3/8" (o9.52)
Unit: ft.
3/4" (19.05)
1.4
1
4.1
10.5
O
1/2 (12.7) 5/8 (15.88)
1/32 (0.8) 5/128 (1.0) over 5/128 (1.0)
48 54
Unit: in. (mm)
Unit: in. (mm)
3/4 (19.05)