Panasonic U-72MF1U9 Technical Data Manual page 33

2. System Design
Indoor unit changes
The indoor unit in room 4, where the corrected indoor unit capacity is less than the maximum load, is increased by one rank.
Selected model
Load (cooling/heating) (BTU/h)
Rated capacity (cooling/heating) (BTU/h)
(5) Corrected capacity (cooling/heating) (BTU/h)
(7) Actual capacity (cooling/heating) (BTU/h)
Total corrected capacity of indoor units (cooling/heating) = 149,008.00/167,398.40
Ruc = 149,008.00/168,609.06 = 0.884 < 1
For both cooling and heating in all rooms, actual capacity is now greater than or equal to the maximum load. Selection is completed.
(2) Calculate the final selection results according to the capacity calculation procedure.
[From calculation of the correction coefficient to calculation of actual capacity]
Rated capacity (BTU/h)
(1) Model
(2) Temp. condition
(3) Tubing length, elevation difference
Distribution ratio
(4) Frosting/defrosting
Result of (2) × (3)
Correction coefficient applied to indoor unit *1
(5) Corrected capacity (BTU/h) *2
(6) Correction coefficient for corrected capacity ratio
(7) Actual capacity (BTU/h)
*1: This varies depending on the values of (2) and (2) × (Distribution ratio in (3)).
*2: Corrected outdoor unit capacity = Rated outdoor unit capacity × (1) × (2) × (3) × (4)
The actual capacity is calculated as shown below.
Cooling: Ruc = (54,600.00 + 35,781.01 + 34,941.99 + 23,684.99) / 168,609.06 = 0884 < 1
Therefore,
Actual cooling capacity of each indoor unit = Corrected cooling capacity of each indoor unit
(In other words, the correction coefficient (6) for the corrected capacity ratio is 1.)
Heating: Ruh = (61,768.40 + 39,234.00 + 39,234.00 + 27,162.00) / 173,189.02 = 0.967 < 1
Therefore,
Actual heating capacity of each indoor unit = Corrected heating capacity of each indoor unit
(In other words, the correction coefficient (6) for the corrected capacity ratio is 1.)
Room 1
Outdoor unit
(indoor unit 1)
Type
Type 54
96 + 96
50,000 /
55,000
192,000 / 54,600 /
216,000 61,400
168,609.06 / 54,600.00 /
173,189.02 61,768.40
54,600.00 /
61,400.00
Ruh = 167,398.40/173,189.02 = 0.967 < 1
Room 1
Outdoor unit
(indoor unit 1)
192,000 / 54,600 /
216,000 61,400
1.0000 /
1.0000
1.0203 / 0.9474 /
1.0000 1.0060
0.8607 / 0.9240 /
0.9009 0.9461
0.8900
1.0171 /
1.0565
1.0000 /
1.0000
168,609.06 / 54,600.00 /
173,189.02 61,768.40
1.0000 /
1.0000
54,600.00 /
61,400.00
2 - 19
Design of 3WAY VRF SYSTEM
Room 2 Room 3 Room 4
(indoor unit 2) (indoor unit 3) (indoor unit 4)
Type 36 Type 36
30,000 / 30,000 /
35,000 35,000
36,000 / 36,000 /
39,000 39,000
35,781.01 / 34,941.99 /
39,234.00 39,234.00
35,781.01 / 34,941.99 /
39,000.00 39,000.00
(Cooling/heating)
Room 2 Room 3 Room 4
(indoor unit 2) (indoor unit 3) (indoor unit 4)
36,000 / 36,000 /
39,000 39,000
0.9474 / 0.9474 /
1.0060 1.0060
0.9030 / 0.8818 /
0.9311 0.9159
1.0491 / 1.0245 /
1.0335 1.0167
0.9939 / 0.9706 /
1.0397 1.0228
0.9939 / 0.9706 /
1.0000 1.0000
35,781.01 / 34,941.99 /
39,234.00 39,234.00
1.0000 / 1.0000 /
1.0000 1.0000
35,781.01 / 34,941.99 /
39,000.00 39,000.00
Type 24
18,500 /
20,000
25,000 /
27,000
23,684.99 /
27,162.00
23,684.99 /
27,000.00
1
2
25,000 /
27,000
0.9474 /
1.0060
3
0.8607 /
0.9009
1.0000 /
1.0000
4
0.9474 /
1.0060
0.9474 /
1.0000
5
23,684.99 /
27,162.00
1.0000 /
1.0000
23,684.99 /
6
27,000.00
7
8