2. MODEL SELECTION
Fig 4

(X
1
, Y
1
)
(X
2
, Y
2
)
(X, Y)
x
y
i)   .    n 
1
and Y
2
using X
1
and X
2
.
ii) Calculate capacity of outdoor unit using
following equation:
Y=(Y
2
-Y
1
) / (X
2
-X
1
)

(X-X1) + Y
1
Capacity ratio of indoor units to outdoor unit, X (%)
Capacity of outdoor unit, Y (kW )
Indoor unit
connecting
capacity (%)
Outdoor
temperature
Indoor temperature
DB WB
16.0°C DB 18.0°C DB 20.0°C DB 24.0°C DB
°C °C
TC IP TC IP TC IP TC IP
120
-15.0 -16.0 11.4 5.57 11.0 5.58 10.6 5.60 10.2 5.62
-10.0 -11.0 14.5 5.62 14.3 5.64 14.0 5.66 13.7 5.68
-5.0 -7.0 15.6 5.71 15.4 5.74 15.1 5.77 14.9 5.79
0.0 -2.0 16.8 5.80 16.5 5.82 16.3 5.86 16.1 5.88
5.0 3.0 17.8 5.92 17.6 5.93 17.4 5.95 17.2 5.96
7.0 6.0 18.7 5.98 18.5 5.98 18.2 5.98 18.0 5.98
10.0 8.0 19.4 5.98 19.1 5.98 18.9 5.98 18.7 5.98
15.0 10.0 20.1 5.10 19.9 5.22 19.6 5.45 19.4 5.84
20.0 15.0 20.4 4.37 20.2 4.44 20.1 4.73 19.9 5.05

         
         
100
-15.0 -16.0 10.5 5.55 10.0 5.52 9.6 5.50 9.2 5.48
-10.0 -11.0 12.8 5.60 12.2 5.61 11.8 5.62 11.3 5.64
-5.0 -7.0 14.4 5.70 13.8 5.78 13.3 5.75 12.9 5.72
0.0 -2.0 15.7 5.76 15.1 5.78 14.5 5.74 13.8 5.68
5.0 3.0 17.0 5.76 16.2 5.61 15.0 5.23 14.0 4.92
7.0 6.0 18.5 5.70 17.4 5.35 16.0 5.07 14.5 4.55
10.0 8.0 18.6 5.56 17. 5 5.25 16.2 4.80 14.7 4.53
15.0 10.0 18.8 5.19 17.6 4.80 16.4 4.61 15.0 4.33
20.0 15.0 19.0 4.63 17.8 4.45 16.7 4.36 15.4 4.08
X
2
X
1
Y
2
Y
1
Capacity ratio of indoor units to outdoor unit X1 = 100 % X = 120 % X2 = 120 %
Capacity of outdoor units (kW) Y1 = 16.0 Y Y2 = 18.2
Y= (18.2-16.0) / (120-100)

(120-100) +16.0 = 18.2 (kW)
- (02 - 12) -
MODEL
SELECTION
MODEL
SELECTION