Mitsubishi Electric CITY MULTI PURY-HP72TNU-A Data Book page 35

8. CAPACITY TABLES
<Heating>
Outdoor Design Wet Bulb Temperature
Total Heating Load
Room1
Indoor Design Dry Bulb Temperature
Heating Load
Room2
Indoor Design Dry Bulb Temperature
Heating Load
<Other>
Indoor/Outdoor Equivalent Piping Length
2. Heating Calculation
(1) Temporary Selection of Indoor Units
Room1
PEFY-P36
Room2
PEFY-P36
(2) Total Indoor Units Capacity
P36 + P36 = P72
(3) Selection of Outdoor Unit
The P72 outdoor unit is selected as total indoor units capacity is P72
PUHY-P72
(4) Total Indoor Units Capacity Correction Calculation
Room1
Indoor Design Dry Bulb Temperature Correction (25ºC)
Room2
Indoor Design Dry Bulb Temperature Correction (25ºC)
Total Indoor Units Capacity (CTi)
CTi = Σ (Indoor Unit Rating × Indoor Design Temperature Correction)
= 11.7 × 0.80 + 11.7 × 0.80
= 18.7 kW
(5) Outdoor Unit Correction Calculation
Outdoor Design Wet Bulb Temperature Correction (2ºC)
Piping Length Correction (30 m)
Defrost Correction
Total Outdoor Unit Capacity (CTo)
CTo = Outdoor Unit Rating × Outdoor Design Temperature Correction × Piping Length
Correction × Defrost Correction
= 23.4 × 0.98 × 0.98 × 0.84
= 18.8 kW
(6) Determination of Maximum System Capacity (CTx)
Comparison of Capacity between Total Indoor Units Capacity (CTi) and Total Outdoor Unit Capacity (CTo)
CTi = 18.7 < CTo = 18.8, thus, select CTi.
CTx = CTi = 18.7 kW
(7) Comparison with Essential Load
Against the essential load 18.2kW, the maximum system capacity is 18.7kW: 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
= 11.7 × 0.80
= 9.4 kW
Room2
Indoor Unit Rating × Indoor Design Temperature Correction
= 11.7 × 0.80
= 9.4 kW
Completed selecting units since the selected units fulfill the heating loads of Room 1, 2.
MEES19K180
Design Condition
Tbl.1 Table of correction factor at frost and defrost
Outdoor inlet air temp. °CWB
Outdoor inlet air temp. °FWB
OK: fulfills the load 9.2kW
PUHY-P72
PUHY-P96
PUHY-P120
PUHY-P144
PUHY-P168
OK: fulfills the load 9.0kW
2 ºC
18.2 kW
25 ºC
9.2 kW
25 ºC
9.0 kW
30 m
11.7 kW (Rated)
0.8
11.7 kW (Rated)
Fig.4 Indoor unit temperature correction
To be used to correct indoor unit only
23.4 kW
0.98
0.80 (Refer to Fig.4)
0.80 (Refer to Fig.4)
Fig.5 Outdoor unit temperature correction
To be used to correct outdoor unit only
0.98
0.98 (Refer to Fig.5)
0.98 (Refer to Fig.6)
0.84 (Refer to Tbl.1)
Fig.6 Correction of refrigerant piping length
6 4 2 1
43 39 36 34
1.00 0.95 0.84 0.83
1.00 0.95 0.84 0.83
1.00 0.93 0.82 0.80
1.00 0.93 0.82 0.80
1.00 0.93 0.82 0.80
Hyper Heating Inverter R2-Series
25
Indoor Temperature [°CD.B.]
2
Outdoor Temperature [°CW.B.]
30
Piping equivalent length (m)
0 -2 -4 -6 -8 -10 -20
32 28 25 21 18 14
0.83 0.87 0.90 0.95 0.95 0.95 0.95
0.83 0.87 0.90 0.95 0.95 0.95 0.95
0.82 0.86 0.90 0.90 0.95 0.95 0.95
0.82 0.86 0.90 0.90 0.95 0.95 0.95
0.82 0.86 0.90 0.90 0.95 0.95 0.95
-4
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