1. VRV III Product Selection Piping selection

2. Selection Considerations
Cooling Load calculations
Heating Load calculations
Internal and Ambient temp
Building layout drawings
Orientation
Room Usage
Fresh Air Requirements
Air and temperature distribution
Noise Levels
Pipe Runs
Unit Dimensions
Aesthetics
Planning Restrictions
Possible future site expansion
Total or sensible capacity selection ?

3. Outdoor and Indoor Unit selection is based on using the capacity index
Indoor unit size
Capacity index 20 25 32
31.25 40 50 63
62.5 80
100
125
140
200
250
To select indoor unit and
unit combinations,
to size pipe work and refnet joints, we use ‘Index’ numbers:
For example the index no of FXZQ20M7V1B is 20

4. Maximum Number of Indoor Units Connected to One Outdoor Unit
Outdoor untis
Indoor units
I.U combination index
Cooling only
Heat pump
Heat recovery
Maximal connectable
Mininum
Maximum
VRV III
VRV II
For VRVIII
For VRVII -
RXYSQ4P7V3B 6 50
130
RXQ5P7W1B
RXYSQ5P7V3B 8
62,5
162,5
RXYSQ6P7V3B 9 70
182
RXQ8P7W1B
RXYQ8P7W1(B)
REYQ8M7W1B 22 13
100
260
RXQ10P7W1B
RXYQ10P7W1(B)
REYQ10M7W1B 25 16
125
325
RXQ12P7W1B
RXYQ12P7W1(B)
REYQ12M7W1B 30 19
150
390
RXQ14P7W1B
RXYQ14P7W1(B)
REYQ14M7W1B 36 20
175
455
RXQ16P7W1B
RXYQ16P7W1(B)
REYQ16M7W1B 40
200
520
RXQ18P7W1B
RXYQ18P7W1(B)
REYQ18M7W1B 44
225
585
RXYQ20P7W1(B)
REYQ20M7W1B 42
250
650
RXYQ22P7W1(B)
REYQ22M7W1B 47
275
715
RXYQ24P7W1(B)
REYQ24M7W1B 51
300
780
RXYQ26P7W1(B)
REYQ26M7W1B 53 32
845
RXYQ28P7W1(B)
REYQ28M7W1B 56
350
910
RXYQ30P7W1(B)
REYQ30M7W1B 60
375
975
RXYQ32P7W1(B)
REYQ32M7W1B 64
400
1040
RXYQ34P7W1(B)
REYQ34M7W1B
425
1105
RXYQ36P7W1(B)
REYQ36M7W1B 34
450
1170
RXYQ38P7W1B
REYQ38M7W1B
475
1235
RXYQ40P7W1B
REYQ40M7W1B 38
500
1300
RXYQ42P7W1B
REYQ42M7W1B
525
1365
RXYQ44P7W1B
REYQ44M7W1B
550
1430
RXYQ46P7W1B
REYQ46M7W1B
575
1495
RXYQ48P7W1B
REYQ48M7W1B
600
1560
RXYQ50P7W1B
625
1625
RXYQ52P7W1B
1690
RXYQ54P7W1B
675
1755

5. Size 50 is the smallest to be connected
Maximum Number of Indoor Units Connected to BS Boxes (required for Heat Recovery Systems)
Branch selector box
Total index
No of indoor units connectable
System type
No of BS boxes connectable
R410a
REYQ8M 13
REYQ10M 16
BSVQ100MVE
Min – Max 8
REYQ12 – 20M 20
REYQ22M 22
BSVQ160MVE
REYQ24 – 32M 32
REYQ34M 34
BSVQ250MVE
160 – 250 5
Size 50 is the smallest to be connected
REYQ35M 36
REYQ38M 38
REYQ40 – 48M 40

6. Indoor unit Selection FXCQ Based on High Fan Speed
For “Low Fan” Speed, capacity
reduction is not published, but the
correction factors from next slide
may be used.

8. Select indoor units for room layout provided
Indoor Unit Selection
Select indoor units for room layout provided
“Example (FXCQ) of where information can be found”
Starting from Engineering data book EEDE06-2 page 795:
Noise Levels details Engineering data book EEDE06-2 page 815
Unit Dimensions Engineering data book EEDE06-2 page 798
Air Distribution Engineering data book EEDE06-2 page 818
Make a record of Model, Fan speed, Total and Sensible Cooling duties

9. Indoor Unit Selection 18 m Room A 8.0kw Sensible Cooling N 6 m 3 m 3 m
Room E
1.65 kw
Sensible
Room D
2.5 kw
Sensible
Room C
2.1 kw
Sensible
Room B
4.2 kw Sensible
3 m
6 m
Room A - General Office
Room B - Meeting Room
Room C - Manager
Room D - Small office
Room E - Reception
3 m
6 m
Rooms A, B and E 400mm ceiling void
Room C 200 mm ceiling void
Room D no void (restricted floor space)
Ceiling Height 2.7m
Internal design 23 deg C db
16 deg C wb
Ambient design 29 deg C db

10. Indoor Unit Selection Possible Solution Note:
Internal design 23 deg C db
16 deg C wb
Ambient design 29 deg C db
Required Sensible
Total
Sensible
Room A
3 x FXFQ40M
8.0 kW
High Speed
10.8 kW
9.0 kW
Room B
1 x FXSQ80M
4.2 kW
Low Speed
5.97 kW
4.73 kW
Room C
1 x FXLQ40M
2.1 kW
3.06 kW
2.3 kW
Room D
1 x FXAQ40M
2.5 kW
3.60 kW
3.31 kW
Room E
1 x FXSQ32M
1.65 kW
2.31 kW
1.88 kW
Note:
The low speed duties were calculated based on the correction factors shown in the previous table.

11. Condensing Unit Selection Considerations
Remember the maximum index connectable
Remember the maximum number of indoor units
Cooling Only, Heat Pump or Heat Recovery
Positioning
Noise levels
Service Access space required

12. Condensing Unit Selection
18 m
Room A
6 m
FXFQ40M
FXFQ40M
FXFQ40M
Room E
Room D
Room C
Room B
3 m
FXAQ40M
FXSQ32M
6 m
FXLQ40M
FXSQ80M
Condensing Unit Base
3 m
6 m

13. Indoor Unit Combination Index
Condensing Unit Selection
Example: using Inverter 2 pipe Heat Pump
Room A 3 x FXFQ40M
Room B 1 x FXSQ80M 80
Room C 1 x FXLQ40M 40
Room D 1 x FXAQ40M 40
Room E 1 x FXSQ32M 31.25
Total Index
Suitable Condensing Unit
RXYQ10P7W1
Outdoor
Unit
Indoor Unit Combination Index
Minimum
Maximum
RXYQ5P7W1
RXYQ8P7W1/REYQ8M
RXYQ10P7W1/REYQ10M
62.5
100
125
162.5
260
325

14. Condensing Unit Selection
Example: using Inverter 2 pipe heat pump
Room A 3 x FXFQ40M
Room B 1 x FXSQ80M 80
Room C 1 x FXLQ40M 40
Room D 1 x FXAQ40M 40
Room E 1 x FXSQ32M 31.25
Total Index
Suitable Condensing Unit
RXYQ10P7W1
Look up condensing unit duty from EEDE06–2 page 196
At indoor temperature of 16 deg C wb and outdoor temp 29 deg C db
Total Cooling with index of 308 = 24,8 kW
Total Cooling at index of 336 = 27.0 kW
Index connected = 336 – = 24.75
27,0 kW – 24,8 = 2.2 kW
336 – 308 = 28
2.2 kW/28 = kW
24.75 x = kW
27.0 kW – kW
= kW

15. Condensing Unit Selection
Example: using Inverter 2 pipe heat pump (Back to the original data selected at high speed)
Corrected
Index
Total
Sensible
Room A
= 3 x FXFQ40M
(high speed)
120
10.80kW
9.0kW
9,66kW
8,04kW
Room B
= 1 x FXSQ80M
(low speed) 80
5.97 kW
4.73 kW
5,60 kW
4.44kW
Room C
= 1 x FXLQ40M 40
3.06 kW
2.3kW
2.73 kW
2.05kW
Room D
= 1 x FXAQ40M
3.6kW
3.3Kw
3.22Kw
2.96Kw
Room E
= 1 x FXSQ32M
31.25
2.37kW
1.88kW
2.08kW
1.69 kW
Total index
311.25
Calculate corrected indoor unit capacity
RXYQ10M total cooling = 25.05kW
FXFQ40M = (40 x 25.05) = 3.22 kW total
Reduce sensible by the same proportion prior to correction calculation
Don’t forget to apply correction for low speed when necessary:
FXSQ80 = (80 x 25.05) x 0.87 = 5,60 kW total
311.25
FXSQ80 = 4.73 x 5,60 = 4.44 kW sensible
5.97

16. Condensing Unit Selection
Example: using Inverter 2 pipe heat pump
Required
Sensible
Corrected
Total
Room A
= 3 x FXFQ40M
8.0 kW
High Speed
9,66kW
8,04kW
Room B
= 1 x FXSQ63M
4.2 kW
Low Speed
5,60 kW
4.44kW
Room C
= 1 x FXLQ40M
2.1 kW
2.73 kW
2.05kW
Room D
= 1 x FXAQ40M
2.5 kW
3.22Kw
2.96Kw
Room E
= 1 x FXSQ25M
1.65 kW
2.08kW
1.69 kW
Not yet ?
Are we finished ?

17. Pipe Length Correction
Example: using Inverter 2 pipe heat pump
Look up capacity correction ratio on page 294 of EEDE06-2
Table RXYQ10P
For Room B FXSQ80M
Run = 20m
Level difference = Outdoor unit 3m below indoor unit
Capacity reduction factor = 0.98

18. Pipe Length Correction
18 m
Room A
6 m
FXFQ40M
FXFQ40M
FXFQ40M
Room E
Room D
Room C
Room B
3 m
FXAQ40M
FXSQ32M
6 m
FXLQ40M
FXSQ80M
Condensing Unit Base
3 m
6 m

19. Pipe Length Correction
(Change in Cooling Capacity)
(H=m)
0.90
0.87
0.85
Outdoor situated
above
Indoor units 50
0.92 40 30
0.95
0.98 20
1.0 10 10 20 30 40 50 60 70 80 90
100
110
……..190 m
Example:
Outdoor unit
3m below
Indoor unit 10
1.0 20
0.98 30
Outdoor situated
below
Indoor units 40
0.95
0.92
0.90
0.87
0.85
(H=m)

20. Pipe Length Correction
Example: using Inverter 2 pipe heat pump
Corrected
Pipe length
Correction factor required
Pipe length corrected
Total
Sensible
Room A
= 1 x FXFQ40M
9,66kW
8,04kW
15M
11M 7M
0.99
3,18kW
2.66kW
Room B
= 1 x FXSQ80M
5,60 kW
4.44kW
20M
0.98
5,49kW
4.35kW
Room C
= 1 x FXLQ40M
2.73 kW
2.05kW
16M
2,68kW
2.02kW
Room D
= 1 x FXAQ40M
3.22Kw
2.96Kw
10M
3.18kW
2,93kW
Room E
= 1x FXSQ32M
2.08kW
1.69 kW 4M
1.00
2.06kW
1.67kW

21. Additional correction due to Defrost operation
Defrost operation protects the outdoor unit coil against freezing:
Happens in heating mode
Performs once max every 2 hours
Duration: between 4 and 8 min
During defrost: outdoor/indoor units’ fans are stopped
No heating is delivered during defrost
Limited cooling is delivered (heat recovery models)
Capacity tables do not take account of this capacity reduction
The heating capacity should be ammended by a correction factor:

22. Summary of selection after corrections
Example: using Inverter 2 pipe heat pump
Required sensible
Result total
Result sensible
Room A
= 3 x FXFQ40M
8.0 kW
High Speed
10,66kW
8,04kW
Room B
= 1 x FXSQ80M
4.2 kW
Low Speed
5,49kW
4.35kW
Room C
= 1 x FXLQ40M
2.1 kW
2,68kW
2.02kW
Room D
= 1 x FXAQ40M
2.5 kW
3.18kW
2,93kW
Room E
= 1 x FXSQ32M
1.65 kW
2.06kW
1.67kW
If selected fan coil unit corrected duty is too low, then that unit has to be re-selected and the complete procedure repeated

23. Would this suit Heat Recovery?
Room A
FXFQ40M
FXFQ40M
FXFQ40M
Room E
Room D
Room C
Room B
FXAQ40M
FXSQ32M
FXLQ40M
FXSQ80M
Meeting Room

24. VRVII Heat Recovery: selection of BS Boxes
Room A
BSVQ160MVE
Min – Max
FXFQ40M
FXFQ40M
FXFQ40M
Room E
Room D
Room C
Room B
FXAQ40M
FXSQ32M
Condensing Unit Base
with REYQ10M
FXLQ40M
FXSQ80M
BS Box
BSVQ100MVE
Min – Max

25. VRV III “P7” Series Selection by VRV Express

26. VRV Selection Software
VRV Express
VRV Selection Software

27. VRV Express

28. VRV Express

29. VRV Express

30. VRV Express

31. VRV Express

32. VRV Express Material list Model Qty Description REYQ12M 1
Heat recovery VRV M R410A
REYQ8M
BSVQ100M 4
Branch selector unit R410A
BSVQ160M 3
FXAQ40M
A - Wall mounted unit
FXFQ50M 2
F - 4-way blow ceiling mounted cassette
FXFQ80M
FXSQ40M
S - Concealed ceiling mounted
FXSQ80M
KHRQ22M20T7
REFNET branch piping kit
KHRQ23M29T7
KHRQ23M64T7
DCS601A51
I controller
BRC1D517 8
Wired remote control
BYC125KJW1
Decoration panel

33. VRV Express Indoor unit details Name Model Tmp C Rq TC Av TC Rq SC
Av SC
Tmp H
Rq HC
Av HC
Airflow
Sound
MCA
WxHxD
Wght °C kW
l/s
dBA A mm kg
First Floor - Room 101
FXFQ50M
22.0
4.0
4.9
3.5
3.8
21.0
2.0
4.5
27-32
0.3
840x246x840 24
First Floor - Room 102
First Floor - Room 103
FXFQ80M
5.5
7.8
3.2
7.1
31-36
0.5 25
First Floor - Room 104
First Floor - Room 105
FXSQ80M
6.2
37-43
1.4
1400x300x800 51
First Floor - Room 106
FXSQ40M
3.0
3.9
2.5
2.9
32-38
0.6
700x300x800 30
Second Floor - Room 201
3.7
2.8
3.6
Second Floor - Room 203
6.0
7.5
5.2
7.2
Second Floor -Room 204
Second Floor - Room 205
FXAQ40M
1.8
34-39
0.4
1050x290x230 14

34. VRV III “P” Series Field Pipe work - Application

35. NEVER install a joint after a header !
VRV refrigerant piping system is based on REFNETS
Advantages of REFNET system: Short dimensioning time
Short installation time
REFNET joint
REFNET header
The VRV system has realized the REFNET piping system to facilitate simple piping construction through original refrigerant control. As a result, not only piping design is drastically simplified but also piping extending in a building is drastically curtained. Dedicated joints and headers are prepared for branch portions where construction is said difficult. Both design and construction are simplified to realize easiness of level same as that of water piping in a central air conditioning system.
Further, sue of the DAIKIN piping/wiring distribution diagram preparation software will enable simple check of piping diagrams.
NEVER install a joint after a header ! ● ● ● ● ●

36. + 30° Joints are to be mounted …. Refnet installation recommendations
Vertically
…..Horizontally +
30°

37. Select refnets according to the capacity according to the capacity
REFNET piping system
Select refnets according to the capacity
Adjust the pipe size
according to the capacity
prototypes
Possibly
match pipe and refnet
using adaptors

38. Refrigerant Pipe Work Maximum “Actual” Piping Limitations
Can become 90 m in certain conditions A
For level differences
above 50m;
One size up of
main liquid pipe
Option kit
40M
15M
90M
165M
Total piping length = 1000M
No Oil traps
No Liquid traps
No Solenoid valves
No Sight glasses
No Driers
No Additional oil
Max pressure test 38.5 bar
190M
Max
EQUIVALENT
LENGTH

39. Field Piping Limitations VRV III P series (Heat pump Inverter)
“Longest” – “shortest” branch = b+c+d+e+l-f <=40m
f, g,h, j, k, l, m, n <= 40m
Pipes b, c, d, e between first and last kit are sized up
For the total piping calculation the actual length of b, c, d, e is counted double if
90m
RXYQ…P
Can be
40m
165m a b c d e
90m
NEVER
INSTALL A
JOINT AFTER
A HEADER j k f h g l n
FXHQ….M
FXCQ….M
FXCQ….M
FXSQ….M
FXAQ….M m
15m
FXLQ….M
FXLQ….M
FXLQ….M

40. VRVII “M” Series Field Piping Limitations (Heat Recovery)
REYQ….M
150m
40M
50m
BSVQ. .M
BSVQ. .M
BSVQ. .M
BSVQ. .M
BSVQ. .M
BSVQ. .M
BSVQ. .M
FXHQ….M
FXCQ….M
FXCQ….M
FXSQ….M
BSVQ. .M
BSVQ. .M
15m
FXLQ….M
FXLQ….M
FXLQ….M
FXLQ….M
FXLQ….M

41. Piping joints required at the first branch
Refnet joints for 2 pipe
Outdoor system type
KHRQ22M20T
RX(Y)Q5
KHRQ22M29T9
RX(Y)Q8~10
KHRQ22M64T
RX(Y)Q12~18 + RXYQ20~22
KHRQ22M75T
RXYQ24~54
Refnet joints for 3 pipe
KHRQ23M29T7
REQY8 – 10
KHRQ23M64T7
REYQ12 – 22
KHRQ23M75T7
REYQ24>
VRV III
VRV II H/R

42. Piping Joints other than the first branch
Refnet joints for 2 pipe
Connectable index
KHRQ22M20T
<200
KHRQ22M29T9
200 - <290
KHRQ22M64T
290 - <640
KHRQ22M75T
>640
Refnet joints for 3 pipe
KHRQ23M20T7
KHRQ23M29T7
KHRQ23M64T7
KHRQ23M75T7
640>
VRV III
VRV II H/R

43. Do NOT increase the size !
Selection of Piping Joints
1st joint corresponds to outdoor unit
2nd Joint according to class total
Possibly, this results into a bigger joint than the 1st joint !
Do NOT increase the size !

44. Piping Headers PLEASE NOTE : Class 250 CANNOT be connected to a header
Refnet header for 2 pipe
Connectable index
KHRQ22M29H
<290
KHRQ22M64H
290 - <640
KHRQ22M75H
640>
Refnet header for 3 pipe
KHRQ23M29H7
<200
200 - <290
KHRQ23M64H7
KHRQ23M75H7
PLEASE NOTE :
Class 250 CANNOT
be connected
to a header

45. Pipe Size connections to the outdoor units Heat Pump model
Outdoor model
Gas pipe
Liquid pipe
RX(Y)Q5
15.9mm
9.5mm
RX(Y)Q8
19.1mm
RX(Y)Q10
22.2mm
RX(Y)Q12, 14, 16
28.6mm
12.7mm
RX(Y)Q18 +RXYQ20-22
RXYQ24
34.9mm
RXYQ26-34
RXYQ36-54
41.3mm

46. Pipe Sizing between refnet branch kits for heat pump models
Piping
Total unit capacity
Gas
(outer diameter)
Liquid
<150
15.9mm
9.5mm
150-->200
19.1mm
200 - >290
22.2mm
290 - <420
28.6mm
12.7mm
420 - <640
640 - <920
34.9mm
>920
41.3mm
Adjust the pipe size
according to the capacity
Possibly, this results into a bigger pipe than the one coming from the outdoor unit !
Do NOT increase the size !

47. Refrigerant pipe Size Connections to Indoor Units
The pipe size of
the indoor unit
Total indoor unit capacity
Gas
Liquid
20, 25, 32, 40, 50
12.7mm
6.4mm
63, 80, 100, 125
15.9mm
9.5mm
200
19.1mm
250
22.2mm
Please note: all the above connections are flared other than the gas pipe connection on the 200 an 250 models being brazed style

48. Pipe Size connections to the outdoor units for Heat recovery
Outdoor model
Gas pipe
Liquid pipe
Discharge pipe
REYQ8
19.1mm
9.5mm
15.9mm
REYQ10
22.2mm
REYQ12
28.6mm
12.7mm
REYQ14, 16
Pipe Sizing between refnet branch kits for Heat recovery
Total unit capacity
Gas
Discharge
Liquid
<63
12.7mm
9.5mm
6.4mm
63 - <200
15.9mm
200 - <290
22.2mm
19.1mm
290 - <420
28.6mm
420 - <640
640 - <920
34.9mm
>920
41.3mm

49. Overall Equivalent length =
Equivalent length = a reference for a pressure drop of an component in the pipe work = length of linear pipes + allowances for fittings
Branch selector box
= 4m
Refnet header
= 1m
Refnet joint
= 0.5m
41.3mm
1 – 5/5 bend
= 0.7m
34.9mm
1 – 3/8 bend
= 0.66m
28.mm
1 – 1/8 bend
22.2mm
7/8 bend
= 0.4m
19.1mm
3/4 bend
= 0.25m
12.7mm
1/2 bend
= 0.22m
9.5mm
3/8 bend
= 0.18m
The following allowances should be allocated to the following components:
Overall Equivalent length =
=(Equivalent length of main pipe work x 0.5) + Equivalent length of branch pipe work

50. Increase only liquid for
What happens when the overall equivalent length from the condensing unit to any indoor unit exceeds 90 m ?
Increase diameter of the Liquid
AND the Gas pipes between
the condenser and the first refnet
BUT ! !
Increase only gas for
RX(Y)Q5P7
Increase only liquid for
RXYQ12,14,24, 36~54 P
REYQ :
The WHOLE RANGE

51. Equivalent length: example of calculation
E. Length
40m
(80m x 0.5)
Overall Equivalent length = = 80m
40m
(No increase in pipe size required)
Section to be
increased in size
Equivalent length
110m
E. Length
40m
(110m x 0.5)
Overall Equivalent length = = 95m
40m
(An increase in main pipe work size is required)
Section to be
increased in size

52. Equivalent length > 90 m
Increase diameter in case of Heat Pump
SYSTEM
REFERENCE
UP TO 90 METERS
OVER 90 METERS
GAS
LIQUID
GAS
LIQUID
RXYQ5P
15.9mm
9.5mm
19.1mm
9.5mm
RXYQ8P
19.1mm
9.5mm
22.2mm
12.7mm
RXYQ10P
22.2mm
9.5mm
22.2mm
12.7mm
RXYQ12P
28.6mm
12.7mm
28.6mm
15.9mm
RXYQ14P
28.6mm
12.7mm
28.6mm
15.9mm
RXYQ16P
28.6mm
12.7mm
28.6mm
15.9mm
RXYQ18P
28.6mm
15.9mm
28.6mm
19.1mm
RXYQ20P
28.6mm
15.9mm
28.6mm
19.1mm
RXYQ22P
28.6mm
15.9mm
28.6mm
19.1mm
RXYQ24P
34.9mm
15.9mm
34.9mm
19.1mm
RXYQ26P
34.9mm
19.1mm
34.9mm
22.2mm
RXYQ28P
34.9mm
19.1mm
34.9mm
22.2mm
RXYQ30P
34.9mm
19.1mm
34.9mm
22.2mm
RXYQ32P
34.9mm
19.1mm
34.9mm
22.2mm
RXYQ34P
34.9mm
19.1mm
34.9mm
22.2mm
RXYQ36P
41.3mm
19.1mm
41.3mm
22.2mm
22.2mm
RXYQ38P
41.3mm
19.1mm
41.3mm
22.2mm
RXYQ40P
41.3mm
19.1mm
41.3mm
22.2mm
RXYQ42P
41.3mm
19.1mm
41.3mm
22.2mm
…….
41.3mm
19.1mm
41.3mm
22.2mm
RXYQ52P
41.3mm
19.1mm
41.3mm
22.2mm
RXYQ54P
41.3mm
19.1mm
41.3mm
22.2mm

53. Equivalent length > 90 m
Increase diameter in case of Heat Recovery
SYSTEM
REFERENCE
UP TO 90 METERS
GAS
DISCHARGE
LIQUID
19.1mm
22.2mm
28.6mm
34.9mm
41.3mm
9.5mm
12.7mm
15.9mm
REYQ8M
REYQ10M
REYQ12M
REYQ14M
REYQ16M
REYQ18M
REYQ20M
REYQ22M
REYQ24M
REYQ26M
REYQ28M
REYQ30M
REYQ32M
REYQ34M
REYQ36M
REYQ38M
REYQ40M
REYQ42M
REYQ44M
REYQ46M
REYQ48M
OVER 90 METERS

54. Piping Between modules forming a Condensing unit Heat pump (P7 series)
To indoor units
No oil equalization line required for P7 models
= Liquid Line
= Gas Line

55. Piping Between modules forming a Condensing unit Heat recovery (M series)
To indoor units
= ¼” (6.4mm) Oil Equalising Line (only for REYQ18 or more)
= Liquid Line
= Gas Line
= Discharge Line

56. Pipe limitations between modules forming a Condensing unit
Branch
Maximum pipe length
10m (13 m equiv.) or less A B C

57. Pipe Sizing Between Outdoor Units
Heat pump branch kit
Two unit connection kit
BHFQ22P1007
Three unit connection kit
BHFQ22M1517
Heat recovery branch kit
KHFQ23M907
BHFQ23M1357

58. Pipe Sizing Between Outdoor Units VRVIII
h m
<
~ 54

59. Pipe Sizing Between Outdoor Units VRVII H/R
h m
<

60. Additional Refrigerant Charge Calculation for VRVIII
takes in consideration the total lengths of liquid piping (m)
TOTAL 22.2 = x 0.37 = +
TOTAL 19.1 = x 0.26 =
TOTAL 15.9 = x 0.18 =
TOTAL = x 0.12 =
TOTAL 9.5 = x =
TOTAL = x =
= R (additional kg R410)
R should be rounded off in units of 0,1 kg

61. Additional Refrigerant Charge Calculation for VRVII H/R
takes in consideration the total lengths of liquid piping (m)
TOTAL 22.2 = x 0.35 = +
TOTAL 19.1 = x 0.25 =
TOTAL 15.9 = x 0.17 =
TOTAL = x 0.11 =
TOTAL 9.5 = x =
TOTAL = x =
0 kg (8-16 HP)
3 kg (18-32 HP)
6 kg (34-48 HP) R=
x 1.15

62. ADDITIONAL REFRIGERANT CHARGE CALCULATION
Field Pipe sizing & Additional “Refrigerant” Charging
Example of centralizing table
BRANCH
SELECTOR BOX
SUCTION
DISCHARGE
LIQUID
SUCTION
LIQUID
JOINT
HEADER A A L 1 U B M 2 V C N 3 W D O 4 X
R_____ M E P 5 Y F Q 6 Z G R
ADDITIONAL REFRIGERANT CHARGE CALCULATION H S
TOTAL = X = +
TOTAL = X =
TOTAL = X = I T A 15 5 B J K 10 10 6 6 6 Z C D E 6 L L U V G W H 4 X Y I 4 F K K 6 J 1 1 2 3 4 5 1 1 M N 1 O 1 P 6 Q 1 32 40 25 80 40 40 2 2 2
15m R S T T 40 40 40
No additional oil required!

63. EN378-2 (2000 Version) Piping material “The material, wall thickness,
R-410A
material
Minimum thickness
Size
t(mm)
C1220-
EN378-2 (2000 Version) ø
6,4 O
0,80 ø
9,5 O
0,80
“The material, wall thickness,
tensile strength, ductility,
corrosion resistance, forming
and testing methods shall be
suitable for the refrigerant
used and withstand the
pressure and stresses which
may occur”
ø12,7 O
0,8
ø15,9 O
0,99
ø19,1
1/2H
0,80
ø22,2
1/2H
0,80
ø28,6
1/2H
0,99
ø34,9
1/2H
1,21
ø41,3
1/2H
1,43
O : Annealed
½ H: Half Hard
For half hard pipes the maximum allowed tensile stress is 61N/mm²
for this reason, the 0.2% proof strength of the half hard pipe shall be
minimum 61N/mm²
The bending radius is more or equal to 3 times the diameter of the pipe
The same requirements are valid
for refnet headers and joints
The maximum working pressure for R-410A VRV P-series is 38 bar

64. Piping Between Outdoor Units: possible patterns
Piping installation recommendations
Piping Between Outdoor Units: possible patterns
Unit A
Unit B
Unit C
To indoor
units
To indoor
units
Unit A
Unit B
Unit C

65. Piping Between Outdoor Units: non recommended patterns
Piping installation recommendations
Piping Between Outdoor Units: non recommended patterns
Unit A
To indoor
units
Unit B
Unit C
Unit A
Unit B
Unit C
To indoor
units
When there is a downward inclination, the oil remains in the pipework

66. Piping installation recommendations
Piping Between Outdoor Units: non recommended patterns
To indoor
units
Unit A
Unit B
Unit C
To indoor
units
Unit A
Unit B
Unit C
Oil collects in the outdoor unit that has stopped operating

67. Piping Between Outdoor Units: non recommended patterns
Piping installation recommendations
Piping Between Outdoor Units: non recommended patterns
Unit A
Unit B
Unit C
To indoor
units
Unit A
Unit B
Unit C
To indoor
units
Oil collects in unit C when the system stops

68. Piping Between Outdoor Units installed at different levels
Piping installation recommendations
Piping Between Outdoor Units installed at different levels
Unit A
Unit B
Max. height
difference
= 5m
To indoor
units
Unit C
Rising height: 200mm or more

69. Piping Between Outdoor Units in case of connections longer than 2m
Piping installation recommendations
Piping Between Outdoor Units in case of connections longer than 2m
Rising height:
200mm or more
Unit A
Unit B
Unit C
To indoor
units
2m or less
2m or more
Rising height:
200mm or more
Rising height:
200mm or more
Unit A
Unit B
Unit C
To indoor
units
2m or less
2m or less