Selection Of Refrigerant Branch Kits - Daikin RWEYQ8T8Y1B Installation And Operation Manual

In case of heat pump system (or 2 pipe):
For the gas piping size: select the size of suction gas piping.
Example:
Downstream capacity for E=capacity index of unit 1
Downstream capacity for D=capacity index of unit 1+capacity index
of unit 2
Piping between BS unit or refrigerant branch kit and indoor
unit: E, G, I
Pipe size for direct connection to indoor unit must be the same as the
connection size of the indoor unit.
Indoor unit capacity index
15, 20, 25, 32, 40, 50
63, 80, 100, 125
200
250
When the equivalent pipe length between outdoor and indoor

units is 80 m or more, the size of the main liquid pipe must be
increased. Depending on the length of the piping, the capacity
may drop, but even in such a case it is possible to increase the
size of the main pipe.
1
1 Outdoor unit
2 Main pipes
3 Increase only liquid pipe size
4 First refrigerant branch kit
5 Indoor unit
HP Class
8+10
16
18+20+24
26+30
Never increase suction gas pipe and HP/LP gas pipe.
The pipe thickness of the refrigerant piping shall comply with the

applicable legislation. The minimal pipe thickness for R410A
piping must be in accordance with the table below.
Pipe Ø (mm)
6.4
9.5
12.7
15.9
19.1
22.2
28.6
34.9
41.3
In case the required pipe sizes (inch sizes) are not available, it is

also allowed to use other diameters (mm sizes), taken the
following into account:
- Select the pipe size nearest to the required size.
- Use the suitable adapters for the change-over from inch
to mm pipes (field supply).
In this case, the additional refrigerant calculation has to be
adjusted as mentioned in
refrigerant charge" on page
RWEYQ8+10T8Y1B
VRV-W IV System Air Conditioner
4P399208-1 – 2015.01
Piping outer diameter size (mm)
Suction gas pipe Liquid pipe
12.7 6.4
15.9
19.1 9.5
22.2
2 3 5
4
Size up
Liquid size (mm)
→
9.5 12.7
→
12.7 15.9
→
15.9 19.1
→
19.1 22.2
Minimal thickness t (mm)
0.80
0.99
0.80
0.99
1.21
1.43
"16.3. Calculating the additional
31.
9.4.

Selection of refrigerant branch kits

Refrigerant Refnets
For piping example, refer to
page 10.
 When using Refnet joints at the first branch counted from the
outdoor unit side, choose from the following table in accordance
with the capacity of the outdoor unit (e.g. Refnet joint a).
Outdoor unit capacity
type (HP)
8+10 KHRQ22M29T9
16+18+20 KHRQ22M64T
24+26+30 KHRQ22M75T
For Refnet joints other than the first branch (e.g. Refnet joint b),

select the proper branch kit model based on the total capacity
index of all indoor units connected after the refrigerant branch.
Indoor unit capacity
index
<200 KHRQ22M20T
200≤x<290 KHRQ22M29T9
290≤x<640 KHRQ22M64T
≥640 KHRQ22M75T
Concerning Refnet headers, choose from the following table in

accordance with the total capacity of all the indoor units
connected below the Refnet header.
Indoor unit capacity
index
<200 KHRQ22M29H
200≤x<290 KHRQ22M29H
290≤x<640 KHRQ22M64H
≥640 KHRQ22M75H
(a) If the pipe size above the Refnet header is Ø34.9 or more, KHRQ22M75H/
KHRQ23M75H is required.
INFORMATION
Maximum 8 branches can be connected to a header.
How to choose a multi outdoor unit connection piping kit

(needed if the outdoor unit capacity type is 16 HP or more).
Choose from the following table in accordance with the number
of outdoor units.
Number of outdoor
units
Heat pump system BHFQ22P1007
Heat recovery system BHFQ23P907
NOTICE
Refrigerant branch kits can only be used with R410A.
"9.3. Selection of piping size" on
2 pipes 3 pipes
KHRQ23M29T9
KHRQ23M64T
KHRQ23M75T
2 pipes 3 pipes
KHRQ23M20T
KHRQ23M29T9
KHRQ23M64T
KHRQ23M75T
2 pipes 3 pipes
KHRQ23M29H
KHRQ23M29H
(a)
KHRQ23M64H
KHRQ23M75H
Multi outdoor unit connection kit
2 3
BHFQ22P1517
BHFQ23P1357
Installation and operation manual
(a)
11