Mitsubishi Electric PUMY-HP36NKMU1, Техническое и сервисное руководство, Страница: 15 / 156

15
OCH733
0 50 100 150 200 250 300 350 400 450 500 550 600
0.70
0.75
0.80
0.85
0.90
0.95
1.00
<Heating>
Design Condition
Outdoor Design Wet Bulb Temperature 35.6ºF (2.0ºC)
Total Heating Load 34.4 kBtu/h
Room1
Indoor Design Dry Bulb Temperature 69.8ºF (21.0ºC)
Heating Load
16.3 kBtu/h
Room2
Indoor Design Dry Bulb Temperature 73.4ºF (23.0ºC)
Heating Load 18.1 kBtu/h
<Other>
Indoor/Outdoor Equivalent Piping Length 328 ft
2. Heating Calculation
(1) Temporary Selection of Indoor Units
Room1
PEFY-P15 17.0 kBtu/h (Rated)
20.0 kBtu/h (Rated)
Room2
PEFY-P18
(2) Total Indoor Units Capacity
P15 + P18 = P33
(3) Selection of Outdoor Unit
The P36 outdoor unit is selected as total indoor units capacity is P33
PUMY-P36NKMU3
42.0 kBtu/h
(4) Total Indoor Units Capacity Correction Calculation
Room1
Indoor Design Dry Bulb Temperature Correction (69.8ºF) 1.00 (Refer to Figure 4)
Room2
Indoor Design Dry Bulb Temperature Correction (73.4ºF) 0.92 (Refer to Figure 4)
CT i = Σ (Indoor Unit Rating × Indoor Design Temperature Correction)
= 17.0 × 1.00 + 20.0 × 0.92
= 35.4 kBtu/h
(5) Outdoor Unit Correction Calculation
Outdoor Design Wet Bulb Temperature Correction (35.6ºF) 1.0 (Refer to Figure 5)
Piping Length Correction (328 ft)
Defrost Correction
0.94 (Refer to Figure 6)
0.89 (Refer to Table 1)
Total Outdoor Unit Capacity (CTo)
Total Indoor Units Capacity (CTi)
CTo = Outdoor Unit Rating × G(CTi)
*1
× Outdoor Design Temperature Correction
× Piping Length Correction × Defrost Correction
= 42.0 × 1.0 × 0.94 × 0.89
= 35.1 kBtu/h
(6) Determination of Maximum System Capacity
Comparison of Capacity between Total Indoor Units Capacity (CTi) and Total Outdoor Unit Capacity (CTo)
CTi = 35.4 > CTo = 35.1, thus, select CTo.
CTx = CTo = 35.1 kBtu/h
(7) Comparison with Essential Load
Against the essential load 34.4 kBtu/h, the maximum system capacity is 35.1 kBtu/h: 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
= 35.1 × (17.0 × 1.00) / (17.0 × 1.00 + 20.0 × 0.92)
= 16.9 kBtu/h OK: fulfills the load 16.3 kBtu/h
Room2
Maximum Capacity × Room1 Capacity after the Temperature Correction/(Room1,2 Total Capacity after the Temperature Correction
= 35.1 × (20.0 × 0.92) / (17.0 × 1.00 + 20.0 × 0.92)
= 18.2 kBtu/h OK: fulfills the load 18.1 kBtu/h
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
59 60.8 62.6 64.4 66.2 68 69.8 71.6 73.4 75.2 77 78.8 80.6
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
Ratio of heating capacity
Indoor Temperature
[°C D.B.]
[°F D.B.]
Indoor
Temperature
-25
-20 -15 -10 -5 0 5 10
15
-13 -4 5 14 23 32 41 50 59
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
Ratio of heating capacity
Outdoor Temperature
[°C W.B.]
[°F W.B.]
21.1°C (70.0°F) D.B.
*1 G(CTi) is used only when greater than 100% indoor model size are connected in total,
refer to STANDARD CAPACITY DIAGRAM.
Capacity ratio
Piping equivalent length (ft)
Total capacity of indoor unit
Table 1 Table of correction factor at frost and defrost
Outdoor Intake temperature <W.B.°F (°C)> 43(6) 37(4) 36(2) 32(0) 28(−2) 25(−4) 21(−6) 18(−8) 14(−10) 5(−15) −4(−20) −13(−25)
Correction factor 1.0 0.98 0.89 0.88 0.89 0.9 0.95 0.95 0.95 0.95 0.95 0.95
Capacity of indoor unit
(kBtu/h)
Model Number
for indoor unit
Model 04 Model 05 Model 06 Model 08 Model 12 Model 15 Model 18 Model 24 Model 27 Model 30 Model 36 Model 48 Model 54
Model
Capacity
4.5 5.6 6.7 9.0 13.5 17.0 20.0 27.0 30.0 34.0 40.0 54.0 60.0