11
OCH634C
Outdoor Intake
Temperature (W.B.°C)
6
4
2
0
−2 −4 −6 −8 −10 −15 −20
Correction factor
1.0 0.98 0.89 0.88 0.89 0.9 0.95 0.95 0.95 0.95 0.95
Capacity of indoor unit
(kW)
P•FY Series
Model Number
for indoor unit
Model
15
Model
20
Model
25
Model
32
Model
40
Model
50
Model
63
Model
71
Model
80
Model
100
Model
125
Model
140
Model
200
Model Capacity
1.9
2.5
3.2
4.0
5.0
6.3
8.0
9.0
10.0
12.5
16.0
18.0
25.0
M,S,P Series
Model Number
for indoor unit
Model
15
Model
20
Model
22
Model
25
Model
35
Model
42
Model
50
Model
60
Model
71
Model
100
-
-
-
Model Capacity
1.7
2.3
2.5
2.9
4.0
4.8
5.7
6.9
8.1
11.2
-
-
-
<Heating>
Design Condition
Outdoor Design Wet Bulb Temperature
2ºC
Total Heating Load
20.5 kW
Room1
Indoor Design Dry Bulb Temperature
21ºC
Heating Load
9.5 kW
Room2
Indoor Design Dry Bulb Temperature
23ºC
Heating Load
11.0 kW
<Other>
Indoor/Outdoor Equivalent Piping Length
50 m
1. Heating Calculation
(1) Temporary Selection of Indoor Units
Room1
PEFY-P80
10.0kW (Rated)
Room2
PEFY-P100
12.5 kW (Rated)
(2) Total Indoor Units Capacity
P80 + P100 = P180
(3) Selection of Outdoor Unit
The P200 outdoor unit is selected as total indoor units capacity is P180
PUMY-P200
25.0 kW
(4) Total Indoor Units Capacity Correction Calculation
Room1
Indoor Design Dry Bulb Temperature Correction (21ºC)
0.96 (Refer to Figure 4)
Room2
Indoor Design Dry Bulb Temperature Correction (23ºC)
0.89 (Refer to Figure 4)
Total Indoor Units Capacity (CTi)
CTi = Σ (Indoor Unit Rating × Indoor Design Temperature Correction)
= 10.0 × 0.96 + 12.5 × 0.89
= 20.7 kW
(5) Outdoor Unit Correction Calculation
Outdoor Design Wet Bulb Temperature Correction (2ºC)
1.0 (Refer to Figure 5)
Piping Length Correction (30 m)
0.93 (Refer to Figure 6)
Defrost Correction
0.97 (Refer to Table 1)
Total Outdoor Unit Capacity (CTo)
CTo = Outdoor Unit Rating × Outdoor Design Temperature Correction × Piping Length
Correction × Defrost Correction
= 25.0 × 1.0 × 0.93 × 0.97
= 22.6 kW
(6) Determination of Maximum System Capacity
Comparison of Capacity between Total Indoor Units Capacity (CTi) and Total Outdoor Unit Capacity (CTo)
CTi = 20.7 < CTo = 22.6, thus, select CTi.
CTx = CTi = 20.7 kW
(7) Comparison with Essential Load
Against the essential load 20.5kW, the maximum system capacity is 20.7 kW: Proper outdoor units have been selected.
(8) Calculation of Maximum Indoor Unit Capacity of Each Room
CTx = CTi, thus, calculate by the calculation below
Room1
Indoor Unit Rating × Indoor Design Temperature Correction
= 10.0 × 0.96
= 9.6 kW
OK: fulfills the load 9.5 kW
Room2
Indoor Unit Rating × Indoor Design Temperature Correction
= 12.5 × 0.89
= 11.1 kW
OK: fulfills the load 11.0 kW
Note: If CTx = CTo, please refer to the <Cooling> section to calculate the Maximum Indoor Unit Capacity of Each Room.
Completed selecting units since the selected units fulfill the heating loads of Room 1, 2.
15
16
17
18
19
20
21
22
23
24
25
26
27
0.6
0.7
0.8
0.9
1.0
1.1
1.2
Ratio of heating capacity
Indoor Temperature [°CD.B.]
Ratio of heating capacity
°CW.B.
Indoor
Temperature
Outdoor Temperature
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
−
20
−
15
−
10
−
5
0
5
10
15
20°C D.B.
Heating capacity correction factor
Piping equivalent length (m)
1.0
0.95
0.9
0.85
0.8
0.75
0.70
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
Figure 4
Indoor unit temperature correction
To be used to correct indoor unit only
Figure 5
Outdoor unit temperature correction
To be used to correct outdoor unit
only
Figure 6
Correction of refrigerant piping length
