Example Of Connection - Daikin VRV III-S RXYMQ6PV4A Service Manual

SiME34-608

4. Example of Connection

Example of connection
(Connection of 8 indoor units
Heat pump system)
Maximum
allowable Between outdoor and indoor units
length
Allowable
Between outdoor and indoor units
height
length Between indoor and indoor units
Allowable length after the branch
Refrigerant branch kit selection
Refrigerant branch kits can only be
used with R-410A.
Pipe size selection
〈Caution on selecting connection pipes〉
• When the equivalent piping length between the outdoor unit and the indoor unit is
90 m or more, make sure to use a thicker pipe as the main pipe on the gas side.
When the air-conditioning ability is reduced due to the refrigerant piping distance,
a thicker pipe may be used also as the main pipe.
[Gas side]
RXYMQ6 type φ19.1 → φ 22.2
Main pipe
Outdoor unit
Enlarge
Caution) In brazing connection in the size increase area in the piping, use a different-
diameter joint for connection. (The different-diameter joint should be arranged
in the local field.)
The connection area is located near the outdoor unit (usually after the first
bending outside the unit).
How to calculate the additional refrigerant to be charged
Additional refrigerant to be charged R (Kg)
R should be rounded off in units of 0.1Kg.
Appendix
Branch with refnet joint
Outdoor unit
a b c d e
A B C D
h i j k
1 2 3 4
Indoor units (1-8)
Pipe length between outdoor and indoor units ≤ 150m
Actual pipe length
Example unit 8: a + b + c + d + e + f + g + p ≤ 150m
Equivalent pipe length between outdoor and indoor units ≤ 175m (assume equivalent pipe length of refnet joint to be 0.5m, that of refnet header to be 1m, calculation purposes)
Equivalent length
Total piping length from outdoor unit to all indoor units ≥10m, ≤ 300m
Total extension length
Difference in height between outdoor and indoor units (H1) ≤ 50m
Difference in height
Difference in height between adjacent indoor units (H2) ≤ 15m
Difference in height
Pipe length from first refrigerant branch kit (either refnet joint or refnet header ) to indoor unit ≤ 40m
Actual pipe length
Example unit 8: b + c + d + e + f + g + p ≤ 40m
Use refnet joint from the following table.
Outdoor unit capacity type
RXYMQ6 type
Piping between outdoor unit and refrigerant branch kit
• Match to the size of the connection piping on the outdoor unit.
Outdoor unit connection pipe size
Outdoor unit
(outer diameter × minimum thickness)
capacity type
Gas pipe
φ 19.1
RXYMQ6
φ 22.2
type
The first refrigerant
branching kit
Indoor unit
 
Total length (m)
R=  
of liquid piping ×0.054
 
size at φ9.5
Branch with refnet joint and refnet header
REFNET joint (A-G)
Outdoor unit
a
A
f g
b
H1 Refnet header
E F G H1
P
l m n
c d e
5 6 7
H2
1 2 3
8
Indoor units (1-8)
Example unit 6: a + b + h ≤ 120m, unit 8: a + i + k ≤ 150m
(Max 40m if the outdoor unit is below)
Example unit 6: b + h ≤ 40m, unit 8:i + k ≤ 40m
Refrigerant branch kit name
KHRP26M22T
Piping between refrigerant branch kits
• Use the pipe size from the following table.
Connection pipe size
(Unit: mm)
Piping size
Piping size (outer diameter × minimum thickness)
Gas pipe
Liquid pipe
φ 15.9
× 1.0 × 1.0
φ 9.5
× 0.8
× 1.0 *
* When the size is larger
 
Total length (m)
+  
of liquid piping ×0.022
 
size at φ6.4
Branch with refnet header
REFNET joint (A • B) Outdoor unit
i
a
B
k
j
7 8
H2
g b c d e
f h
1 2 3 4
4 5 6
Indoor units (1-8)
Example unit 8: a + i ≤ 150m
Example unit 8: i ≤ 40m
How to select the refnet header
• Choose from the following table below the REFNET header according
to the number of units on the system.
Outdoor unit capacity type Refrigerant branch kit name
KHRP26M22H (Max. 4 branch)
RXYMQ6 type
KHRP26M33H (Max. 8 branch)
Between refrigerant branch kit and indoor unit
• Pipe size for direct connection to indoor unit must be the
same as the connection size of indoor unit.
(Unit: mm) Indoor unit connection pipe size
Indoor unit
(outer diameter × minimum thickness)
capacity type
Gas pipe
Liquid pipe
φ 9.5
× 0.8
20 · 25 · 32 ·
φ 12.7
× 0.8
40 · 50 type
63 · 80 · 100 ·
φ 15.9
× 1.0
125 type
Example for refrigerant branch using refnet joint and refnet header
The piping
a: 9.5 × 30m d: 9.5 × 13m g: 16.4 × 10m
lengths are as
b: × 10m e: 6.4 × 10m h: 16.4 × 20m
9.5
at right
c: 09.5 × 10m f : 6.4 × 10m i :
R= 73 0.054 + 69 0.022 = 5.46
5.5
a+b+c+d+i e+f+g+h+j+k
Example of Connection
Refnet header
H1
f g h i
5 6 7
H2
8
(Unit: mm)
Piping size
Liquid pipe
φ 6.4
× 0.8
φ 9.5
× 0.8
j : 16.4 × 10m
k: 16.4 × 19m
9.5 × 10m
227