Mitsubishi Electric PUMY-P200YKM1, Техническое и сервисное руководство

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10
OCH634C
4-1. SELECTION OF COOLING/HEATING UNITS
4
DATA
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 1.7 2.2 2.8 3.6 4.5 5.6 7.1 8.0 9.0 11.2 14.0 16.0 22.4
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 1.5 2.0 2.2 2.5 3.5 4.2 5.0 6.0 7.1 10.0 - - -
1. Cooling Calculation
(1) Temporary Selection of Indoor Units
Room1
PEFY-P80 9.0kW (Rated)
Room2
PEFY-P100 11.2 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 22.4 kW
(4) Total Indoor Units Capacity Correction Calculation
Room1
Indoor Design Wet Bulb Temperature Correction (20ºC) 1.03 (Refer to Figure 1)
Room2
Indoor Design Wet Bulb Temperature Correction (18ºC) 0.90 (Refer to Figure 1)
Total Indoor Units Capacity (CTi)
CTi = Σ (Indoor Unit Rating × Indoor Design Temperature Correction)
= 9.0 × 1.03 + 11.2 × 0.90
= 19.4 kW
(5) Outdoor Unit Correction Calculation
Outdoor Design Dry Bulb Temperature Correction (38ºC) 0.93 (Refer to Figure 2)
Piping Length Correction (40 m) 0.90 (Refer to Figure 3)
Total Outdoor Unit Capacity (CTo)
CTo = Outdoor Rating × Outdoor Design Temperature Correction × Piping Length Correction
= 22.4 × 0.93 × 0.90
= 18.7 kW
(6) Determination of Maximum System Capacity
Comparison of Capacity between Total Indoor Units Capacity (CTi) and Total Outdoor Unit Capacity (CTo)
CTi = 19.4 > CTo = 18.7, thus, select CTo.
CTx = CTo = 18.7 kW
(7) Comparison with Essential Load
Against the essential load 18.0kW, the maximum system capacity is 18.7 kW: Proper outdoor units have been selected.
(8) Calculation of Maximum Indoor Unit Capacity of Each Room
CTx = CTo, thus, calculate by the calculation below
Room1
Maximum Capacity × Room1 Capacity after the Temperature Correction/(Room1,2 Total Capacity after the Temperature Correction)
= 18.7 × (9.0 × 1.03)/(9.0 × 1.03 + 11.2 × 0.90)
= 9.0 kW OK: fulfills the load 8.0 kW
Room2
Maximum Capacity × Room2 Capacity after the Temperature Correction/(Room1,2 Total Capacity after the Temperature Correction)
= 18.7 × (11.20 × 0.90)/(9.0 × 1.03 + 11.2 × 0.90)
= 9.7 kW OK: fulfills the load 9.5 kW
Note: If CTx = CTi, please refer to the <Heating> section to calculate the Maximum Indoor Unit Capacity of Each Room.
Go on to the heating trial calculation since the selected units fulfill the cooling loads of Room 1, 2.
Figure 1 Indoor unit temperature correction
To be used to correct indoor unit only
Figure 2 Outdoor unit temperature correction
To be used to correct outdoor unit
only
Figure 3 Correction of refrigerant piping length
<Cooling>
Design Condition
Outdoor Design Dry Bulb Temperature 38ºC
Total Cooling Load 18.0 kW
Room1
Indoor Design Dry Bulb Temperature 27ºC
Indoor Design Wet Bulb Temperature 20ºC
Cooling Load 8.0 kW
Room2
Indoor Design Dry Bulb Temperature 24ºC
Indoor Design Wet Bulb Temperature 18ºC
Cooling Load 9.5 kW
<Other>
Indoor/Outdoor Equivalent Piping Length 40 m
Indoor Temperature [°CW.B.]
Ratio of cooling capacity
15 16 17 18 19 20 21 22 23 24
0.4
0.6
0.8
1.0
1.2
Ratio of cooling capacity
Outdoor Temperature [°C D.B.]
-5.0 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
Indoor Temperature
19°C W.B
Total capacity of indoor unit
Cooling capacity correction factor
Piping equivalent length (m)
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
11.2
16.8
22.4
29.1
0.70
0.75
0.80
0.85
0.90
0.95
1.00