Panasonic U-72MF1U9 Technical Data Manual page 28

1. Model Selecting and Capacity Calculator
Graph of indoor unit capacity characteristics (2 – (2))
Indoor unit cooling capacity characteristics
120
110
100
90
80
Graph of capacity change characteristics resulting from tubing length and elevation difference (1 / 2 – (3))
<Cooling>
1
Base capacity
change rate
164
131
94
98
96
2
98
66
100
33
%
0
-33
3
-66
-98
-131
0 33 66 98
4
The positive side for the elevation difference indicates that the outdoor unit is installed at a higher position than the indoor units.
The negative side indicates the opposite.
The capacity loss that is caused by the tubing length can be reduced by increasing the sizes of the discharge tubes and suc-
tion tubes. Refer to Table 2-9 and make the appropriate changes. However be sure that the total length does not exceed the
5
maximum.
* The only sizes which can be increased are the LM (main tube with the largest diameter) gas tubes, and the changes are
limited to those shown in Table 2-9.
In addition, note that the additional refrigerant charge is determined only by the narrow-tube size.
6
Table 2-9 Equivalent Length Correction Coeffi cient when the Size of the Discharge Tubes and Suction Tubes (LM)
is Increased
Standard tubing diameter
(gas tube, in.(mm))
Tubing diameter after change
7
(gas tube,in.(mm))
Equivalent length correction
coefficient
* If the size of the discharge tubes and suction tubes (LM) have been increased, apply the correction coeffi cient from Table
8
2-9 and calculate the equivalent length of the LM section.
Equivalent length of tubing after size increase
= Standard tubing equivalent length × Equivalent length correction coeffi cient
indicates the rating point.
57 59 60 62 64 66 68 69 71 73 75 77
Indoor air intake temp. ( °F WB)
92 90 88 86 84 82 80
*1
131 164 197 230 262 295 328 361 394 427 459 492
Equiv alent length (ft)
ø5/8"
ø1/2"
(ø15.88)
(ø12.7)
ø5/8" ø3/4"
(ø15.88) (ø19.05)
0.4
Indoor unit heating capacity characteristics
110
105
100
95
90
59 60 62 64 66 68 69 71 73 75 77 78 80
Indoor air intake temp. ( °F DB)
<Heating>
Base capacity
change rate
78 76
164
131
98
66
33
0
-33
-66
-98
-131
0 33 66
ø3/4" ø7/8"
(ø19.05) (ø22.22)
ø7/8" ø1-1/8"
(ø22.22) (ø28.58)
0.5
2 - 14
Design of 3WAY VRF SYSTEM
indicates the rating point.
98 131 164 197 230 262 295 328 361 394 427 459 492
Equivalent length (ft)
ø1-1/8"
(ø28.58)
ø1-3/8"
(ø34.92)
0.6