Daikin VRV IV-S Series, Engineering Data

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Selection Procedure EDMT331529A
22 General Information
-Confirm capacity correction factor for piping length and level difference (K1)
-Calculate capacity correction factor for piping heat loss (K2)
(K2) = 1 + (heat loss factor per meter of piping × (equivalent piping length – 7.5m)) / 100
Heat loss factor per meter at 33ºC is calculated as below.
Heat loss factor per meter = 0.022 + (0.030 – 0.022) × (33 – 30) / (35 – 30) = 0.0268
Using “Equivalent piping length = 30m” and “Heat loss factor per meter = 0.0268”,
(K2) = 1 + (0.0268 × (30 – 7.5)) / 100 = 1.006
-Calculate the corrected capacity of RXYMQ8AY1 (C) by using (K1) and (K2).
Corrected capacity of RXYMQ8AY1 (C) = (B) × (K1) / (K2) (add defrost correction factor for heating capacity)
17.7 × 0.95 / 1.006 = 16.7 (kW)
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, 16.7 kW (C)
≥
15.0 kW (A), so the selection is complete.
Cooling Ambient temperature
Heat loss factor per
meter of piping (%)
5°C 10°C 15°C 20°C 25°C 30°C 35°C 40°C
0.000 0.000 0.004 0.009 0.014 0.022 0.030 0.038
Heating Ambient temperature
Heat loss factor per
meter of piping (%)
-15°C -10°C -5°C 0°C 5°C 10°C 15°C 20°C
0.100 0.093 0.086 0.078 0.071 0.064 0.057 0.049
(K1) = 0.95
0.95