Daikin SV1A25AJV1B - Page 55

13 | Special requirements for R32 units
Installer and user reference guide
55
SV1A25AJV1B+SV4~8A14AJV1B
VRV 5 safety valve unit
4P749917-1 – 2023.09
-
38.01
115
P
INTERNAL
[Pa]
-300
-250
-200
-150
-100
0
0
50
100
150
200
250
300
-50
AFR
OUT
[m³/h]
Note: These curves present the internal pressure of the SV unit compared to an
ambient pressure of 101325Pa.
Use the curve of the outlet pressure (P
OUT
) in function of the airflow rate (AFR
OUT
)
for the SV unit. With an airflow rate of 115 m³/h, the resulting pressure drop
generated by the SV unit is 38.3Pa.
-300
-250
-200
-150
-100
0
0
50
100
150
200
250
300
-50
P
OUT
[Pa]
AFR
OUT
[m³/h]
-
38.33
115
Use the curves, with instructions how to read them, of the manufacturer of the
components to find the pressure drop generated by all components in the
ductwork. A conversion of units might be required. Beware that for ducting, the
pressure drop from the manufacturer might be given per unit length of ducting
(units are for example Pa/m). Multiply this value by the duct length to find the total
pressure drop.
AFR [m³/h]
AFR [m³/h]
ΔP
[Pa/m]
ΔP
[Pa]
115
1
115
8
Ducting Bends
EXAMPLE
Write down the pressure drop of each component in an overview table. Sum up
the pressure drops.
Nº Indication Type AFR [m³/h] Length [m] ∆P [Pa/m] ∆P [Pa]
1 a SV unit 115 - - 38.3
2 b Duct “ 5 1 5
3 c Bend “ - - 8
4 b Duct “ 10 1 10
5 c Bend “ - - 8
6 b Duct “ 2 1 2
7 d Expander “ - - 4
8 e Duct “ 6 0.5 3
9 f Reducer “ - - 6
10 b Duct “ 2 1 2
11 b Duct “ 1 1 1
12 g Non-return valve “ - - 11
13 b Duct “ 1 1 1
14 h Wall grill “ - - 15
Total pressure drop (sum of rows 1 to 14) 114.3
Select a fan with the required flow of 115 m³/h and a total pressure rise of
114.3Pa.
Note: For ease of installation, we recommend to use in-line duct fans.