Daikin VRV IV Installer And User Reference Manual page 70

18 | Piping installation
D: Piping between refrigerant branch kits
E: Piping between refrigerant branch kit and indoor unit
Installer and user reference guide
70
Outdoor unit capacity
type (HP)
8
10
12~16
18~22
24
26~34
36~42
Choose from the following table in accordance with the indoor unit total capacity
type, connected downstream. Do not let the connection piping exceed the
refrigerant piping size chosen by the general system model name.
Indoor unit capacity index
<150
150≤x<200
200≤x<290
290≤x<420
420≤x<640
640≤x<920
≥920
Example:
▪ Downstream capacity for E=capacity index of unit 1
▪ Downstream capacity for D=capacity index of unit 1+capacity index of unit 2
Pipe size for direct connection to indoor unit must be the same as the connection
size of the indoor unit (in case indoor unit is VRV DX indoor or Hydrobox).
Indoor unit capacity index
15~50
63~140
200
250
▪ When the equivalent pipe length between outdoor and indoor units is 90 m or
more, the size of the main pipes (both gas side and liquid side) must be
increased. Depending on the length of the piping, the capacity may drop, but
even in such a case the size of the main pipes has to be increased. More
specifications can be found in the technical engineering data book.
Piping outer diameter size (mm)
Gas pipe
19.1
22.2
28.6
28.6
34.9
34.9
41.3
Piping outer diameter size (mm)
Gas pipe
15.9
19.1
22.2
28.6
34.9
41.3
Piping outer diameter size (mm)
Gas pipe
12.7
15.9
19.1
22.2
Liquid pipe
9.5
9.5
12.7
15.9
15.9
19.1
19.1
Liquid pipe
9.5
12.7
15.9
19.1
Liquid pipe
6.4
9.5
RXMLQ8 + RXYLQ10~14T7Y1B*
VRV IV system air conditioner
4P543427-1A – 2020.10