2 - 328
R2 (HIGH
COP)
8. CAPACITY TABLES
YKB/YLM 2nd
MEE15K022
8-1. Selection of Cooling/Heating Units
Indoor Temperature [°CW.B.]
Ratio of cooling capacity
15
16
17
18
19
20
21
22
23
24
0.8
0.9
1.0
1.1
1.2
1.2
1.0
0.9
0.8
0.7
0.6
1.1
1.3
Ratio of cooling capacity
-5
23
0
32
5
41
10
50
15
59
20
68
25
77
30
86
35
95
40
104
45
113
°CD.B.
°FD.B.
Indoor Temperature
Outdoor Temperature
19°CW.B.
66°FW.B.
<Cooling>
Design Condition
Outdoor Design Dry Bulb Temperature
43 ºC
T
otal Cooling Load
18.0 kW
Room1
Indoor Design Dry Bulb Temperature
27 ºC
Indoor Design Wet Bulb Temperature
20 ºC
Cooling Load
8.0 kW
Room2
Indoor Design Dry Bulb Temperature
24 ºC
Indoor Design Wet Bulb Temperature
17 ºC
Cooling Load
10.0 kW
<Other>
Indoor/Outdoor Equivalent Piping Length
50 m
1. Cooling Calculation
(1) Temporary Selection of Indoor Units
Room1
PEFY-P80
9 kW (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
PUHY-P200
22.4 kW
(4) Total Indoor Units Capacity Correction Calculation
Room1
Indoor Design Wet Bulb Temperature Correction (20ºC)
1.04 (Refer to Fig.1)
Fig.1
Indoor unit temperature correction
T
o be used to correct indoor unit only
Fig.2
Outdoor unit temperature correction
T
o be used to correct outdoor unit only
Fig.3
Correction of refrigerant piping length
Room2
Indoor Design Wet Bulb Temperature Correction (17ºC)
0.95 (Refer to Fig.1)
CT
i
=
Σ
(
I
n
d
o
o
r
U
n
i
t
R
a
t
i
n
g
×
I
n
d
o
o
r
D
e
s
i
g
n
Temperature Correction)
= 9.0 × 1.04 + 1
1.2 × 0.95
= 20.0 kW
(5) Outdoor Unit Correction Calculation
Outdoor Design Dry Bulb Temperature Correction (43ºC)
0.94 (Refer to Fig.2)
Piping Length Correction (50 m)
0.94 (Refer to Fig.3)
T
otal Outdoor Unit Capacity (CTo)
T
otal Indoor Units Capacity (CTi)
CT
o = Outdoor Rating × Outdoor Design Temperature Correction × Piping Length Correction
= 22.4 × 0.94 × 0.94
= 19.9 kW
(6) Determination of Maximum System Capacity (CTx)
Comparison of Capacity between Total Indoor Units Capacity (CTi) and T
otal Outdoor Unit Capacity (CTo)
CTi = 20.0 > CTo = 19.9, thus, select CT
o.
CTx = CTo = 19.9 kW
(7) Comparison with Essential Load
Against the essential load 18.0kW, the maximum system capacity is 19.9kW: 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 T
emperature Correction
= 19.9 × (9.0 × 1.04)/(9.0 × 1.04 + 1
1.2 × 0.95)
= 9.3 kW
OK: fulfills the load 8.0kW
Room2
Maximum Capacity × Room2 Capacity after the Temperature Correction/(Room1,2T
otal Capacity after the Temperature Correction)
= 19.9 × (11.20 × 0.95)/(9.0 × 1.04 + 11.2 × 0.95)
= 10.6 kW
OK: fulfills the load 10.0kW
Go on to the heating trial calculation since the selected units fulfill the cooling loads of Room 1, 2.
Piping equivalent length (m)
1
0.90
0.80
0.95
0.85
0.75
0.65
0.70
Cooling capacity correction factor
0
20
40
60
80
100
120
140
160
180
T
otal capacity of indoor unit
100
150
200
260
