13
OCH668G
<Heating>
Design Condition
Outdoor Design Wet Bulb Temperature
2ºC
Total Heating Load
13.2 kW
Room1
Indoor Design Dry Bulb Temperature
23ºC
Heating Load
5.4 kW
Room2
Indoor Design Dry Bulb Temperature
23ºC
Heating Load
7.8 kW
<Other>
Indoor/Outdoor Equivalent Piping Length
60 m
2. Heating Calculation
(1) Temporary Selection of Indoor Units
Room1
PEFY-P50
6.3 kW (Rated)
Room2
PEFY-P71
9.0 kW (Rated)
(2) Total Indoor Units Capacity
P50 + P71 = P121
(3) Selection of Outdoor Unit
The SP125 outdoor unit is selected as total indoor units capacity is P121
PUMY-SP125
16.0 kW
(4) Total Indoor Units Capacity Correction Calculation
Room1
Indoor Design Dry Bulb Temperature Correction (23ºC)
0.88 (Refer to Figure 4)
Room2
Indoor Design Dry Bulb Temperature Correction (23ºC)
0.88 (Refer to Figure 4)
CT
i = Σ (Indoor Unit Rating × Indoor Design Temperature Correction)
= 6.3 × 0.88 + 9.0 × 0.88
= 13.5 kW
(5) Outdoor Unit Correction Calculation
Outdoor Design Wet Bulb Temperature Correction (2ºC)
1.00 (Refer to Figure 5)
Piping Length Correction (60 m)
Defrost Correction
0.96 (Refer to Figure 6)
0.89 (Refer to Table 1)
Total Outdoor Unit Capacity (CTo)
Total Indoor Units Capacity (CTi)
CTo = Outdoor Unit Rating
×
Outdoor Design Temperature Correction
×
Piping Length
Correction
×
Defrost Correction
= 16.0 × 1.00 × 0.96 × 0.89
= 13.7 kW
(6) Determination of Maximum System Capacity
Comparison of Capacity between Total Indoor Units Capacity (CTi) and Total Outdoor Unit Capacity (CTo)
CTi = 13.5 < CTo = 13.7, thus, select CTi.
CTx = CTi = 13.5 kW
(7) Comparison with Essential Load
Against the essential load 13.2kW, the maximum system capacity is 13.5 kW: Proper indoor 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
= 6.3 × 0.88
= 5.5 kW
OK: fulfills the load 5.4 kW
Room2
Indoor Unit Rating
×
Indoor Design Temperature Correction
= 9.0× 0.88
= 7.9 kW
OK: fulfills the load 7.8 kW
Completed selecting units since the selected units fulfill the heating loads of Room 1, 2.
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
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.]
−20
−15
−10
−5
0
5
10
15
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
Ratio of heating capacity
Outdoor Temperature [°C W.B.]
20°C D.B
Note: If CTx = CTo, please refer to the <Cooling> section to calculate the Maximum Indoor Unit Capacity of Each Room.
0
20
40
60
80
0.50
0.55
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
Capacity ratio
Piping equivalent length (m)
Capacity of indoor unit
P•FY
Series
Model Number
for indoor unit
(kW type)
Model 10 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 Capacity
1.4
1.9
2.5
3.2
4.0
5.0
6.3
8.0
9.0
10.0
12.5
16.0
18.0
M Series
S Series
P Series
Model Number
for indoor unit
(kW type)
Model 15 Model 18 Model 20 Model 22 Model 25 Model 35 Model 42 Model 50 Model 60 Model 71 Model 80 Model 100
-
Model Capacity
1.7
2.1
2.3
2.5
2.9
4.0
4.8
5.7
6.9
8.1
9.3
11.2
-
Table 1 Table of correction factor at frost and defrost
Outdoor Intake Temperature
(°C W.B.)
6
4
2
0 -2 -4 -6 -8 -10 -15 -20
Correction factor
1.00
0.98 0.89
0.88
0.89 0.90 0.95 0.95 0.95 0.95 0.95
