Daikin VRV EMERION RXYQ-AATJA, Руководство по конструкции

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RXYQ-AATJA / RXYQ-AAYDA EDUS342305-D
-Confirm capacity correction factor by piping length and level difference (K1)
120
200
0.94 (K1) = 0.94
-Calculate capacity correction factor by piping heat loss (K2)
(K2) = 1 + (heat loss factor per feet of piping × (equivalent piping length – 25 ft.)) / 100
In cooling mode, heat loss factor per feet at 93°F is calculated as below.
(R) Heat loss factor per feet = 0.072*
2
+ (0.098*
1
– 0.072*
2
) × (93*
3
– 86*
4
) / (95*
5
– 86*
4
) = 0.0922
Using “Equivalent piping length = 200 ft” and “Heat loss factor per feet = 0.0922”,
(K2) = 1 + (0.0922 × (200 – 25)) / 100 = 1.161
Cooling Ambient temperature
Heat loss factor per feet
of piping (%)
Heating Ambient temperature
Heat loss factor per feet
of piping (%)
5°F 14°F 23°F 32°F 41°F 50°F 59°F 68°F
0.328 0.305 0.282 0.256 0.233 0.210 0.187 0.161
41°F
0.000
50°F
0.000
59°F
0.013
68°F
0.030
77°F
0.046
86°F
*4
0.072
*2
93°F
*3
(R)
95°F
*5
0.098
*1
104°F
0.125
-Calculate the corrected capacity of RXYQ192AAYDA (C) by using (K1) and (K2).
Corrected capacity of RXYQ192AAYDA (C) = (B) × (K1) / (K2) (add defrost correction factor for heating capacity)
Therefore (C) = 204.25 × 0.94 / 1.161 = 165.5 MBH
If the corrected capacity (C) is the same or greater than the required total heat load (A), selection is complete.
If (C) < (A), return to Procedure [3]–2 and provisionally select a larger outdoor unit.
In this example, 165.5 MBH (C) < 173.0 MBH (A), so need to select a larger outdoor unit.
The capacity of RXYQ216AAYDA at the same condition is 177.54 MBH, which is more than the heat load (A): 173.0 MBH.
So the selection is complete.