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1-13. Example of Tubing Size Selection and Refrigerant Charge Amount
Additional refrigerant charging
Based on the values in Tables 1-3, 4, 5, 7, 10-1 and 10-2, use the liquid tubing size and length, and calculate the amount of addi-
tional refrigerant charge using the formula below.
Required additional
= Necessary Amount of Additional Refrigerant Charge Per Outdoor Unit
refrigerant charge (oz)
(a) : Liquid tubing
Total length of ø7/8" (ft.)
(b) : Liquid tubing
Total length of ø3/4" (ft.)
(c) : Liquid tubing
Total length of ø5/8" (ft.)
● Charging procedure
Be sure to charge with R410A refrigerant in liquid form.
1. After performing a vacuum, charge with refrigerant from the liquid tubing side. At this time, all valves must be in the "fully
closed" position.
2. If it was not possible to charge the designated amount, operate the system in Cooling mode while charging with refrigerant
from the gas tubing side. (This is performed at the time of the test run. For this, all valves must be in the "fully open" position.
However if only one outdoor unit is installed, a balance tube is not used. Therefore, leave the valves fully closed.)
Charge with R410A refrigerant in liquid form.
With R410A refrigerant, charge while adjusting the amount being fed a little at a time in order to prevent liquid refrigerant
from backing up.
● After charging is completed, turn all valves to the "fully open" position.
● Replace the tubing covers as they were before.
1. R410A additional charging absolutely must
CAUTION
2. The R410A refrigerant cylinder has a gray
3. The R410A refrigerant cylinder includes a
4. Due to differences in the refrigerant, pres-
Example:
Outdoor unit
09663
09663
model
model
B
● Example of each tubing length
Main tubing
LA = 131 ft.
LB = 16 ft.
LC = 16 ft.
+ 3.93 × (a) + 2.78 × (b) + 1.99 × (c) + 1.38 × (d) + 0.602 × (e) + 0.279 × (f)
be done through liquid charging.
base color, and the top part is pink.
siphon tube. Check that the siphon tube is
present. (This is indicated on the label at the
top of the cylinder.)
sure, and refrigerant oil involved in installa-
tion, it is not possible in some cases to use
the same tools for R22 and for R410A.
A
LC
LB
LA
1
2
48 model
48 model
Distribution joint tubing
Outdoor side
A = 7 ft.
B = 7 ft.
(d) : Liquid tubing
Total length of ø1/2" (ft.)
(e) : Liquid tubing
Total length of ø3/8" (ft.)
( f ) : Liquid tubing
Total length of ø1/4" (ft.)
Balance tube
Use a flathead screwdriver and
open by turning the part with the
screw groove to the right,
from "–" to "|".
Liquid tube
Use a hex wrench (width 5/32 inch)
and turn to the left to open.
3
4
48 model
36 model
Indoor side
1 = 98 ft.
2 = 16 ft.
3 = 16 ft.
4 = 65 ft.
14
Gas tube
Use a flathead screwdriver and
open by turning the part with the
screw groove to the right,
from "–" to "|".
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