11
Table 11 Necessary Amount of Additional Refrigerant Charge Per Outdoor Unit
Further charge a certain amount listed below in addition to the amount of refrigerant charge.
Combination number of outdoor unit
1
2
3
Additional amount
oz (
g
)
70.5 (2,000)
141.0 (4,000)
212 (6,000)
Necessary Amount of Additional Refrigerant Charge for All Indoor Unit Cooling Capacity
Charge a refrigerant amount calculated in the following formula according to the total amount of indoor unit cooling capacity.
Additional refrigerant amount when cooling capacity is BTU/h = Cooling capacity (BTU/h) × 1.034 × 0.001 + 10.6 (oz)
or Additional refrigerant amount when cooling capacity is kW = Cooling capacity (kW) × 1000 × 0.1 + 300 (
g
)
Table 12 Necessary Amount of Additional Refrigerant Charge Per ft. (or per meter), According to Discharge Tubing Size
Discharge tubing size
inch
ø1/2"
ø5/8"
ø3/4"
ø7/8"
ø1-1/8"
ø1-3/8"
(mm)
(ø12.7)
(ø15.88)
(ø19.05)
(ø22.22)
(ø28.58)
(ø34.92)
Additional amount
oz/ft.
0.129
0.226
0.333
0.441
0.763
1.118
(
g
/m)
(12)
(21)
(31)
(41)
(71)
(104)
1-9. System Limitations
Table 13 System Limitations
Max. No. allowable connected outdoor units
3 *
2
Max. capacity allowable connected outdoor
units
360,000 BTU/h
(30 ton, 105.5 kW)
Max. connectable indoor units
52 *
1
Max. allowable indoor/outdoor capacity ratio
50 – 150 % *
3
*1: In the case of 20 ton (70.3kW) or smaller units, the number is
limited by the total capacity of the connected indoor units.
*2: Up to 3 units can be connected if the system has been extended.
*3: It is strongly recommended that you choose the unit so the load
can become between 50 and 130%.
Table 14 System Limitations of Total Refrigerant Amount
Combination number of outdoor unit
1
2
3
Upper limit
oz (
g
)
1,763 (50,000)
2,821 (80,000)
3,703 (105,000)
Make sure the values calculated using the following formula should not exceed the maximum allowable values (Table 14).
Total refrigerant amount = Refrigerant charge amount at shipment (for outdoor unit)
+
Necessary amount of additional refrigerant charge per ft. (or per meter) according to liquid tubing size
+
Necessary amount of additional refrigerant charge per outdoor unit
+
Necessary amount of additional refrigerant charge for all indoor unit cooling capacity
+
Necessary amount of additional refrigerant charge per ft. (or per meter) according to discharge tubing size
Maximum number of connectable indoor units
when connected with minimum capacity
Total system
tonnage
Number of
indoor units
Total system
tonnage
Number of
indoor units
6
14
16
38
8
19
18
43
10
24
20
48
12
28
22~30
52
14
33
* Additional refrigerant charge amount of discharge tubing should be less than 317 oz
(9,000
g
).
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2018/7/4 13:30:27