Daikin VRV II Series Instruction manual

technical data
Systems
VRVII & VRV-WII Features

• Systems • VRVII & VRV-WII features 1
• VRVII & VRV-WII features
VRVII & VRV-WII features
Table of contents
1 Creating maximum comfort
Inverter technology - VRVII & VRV-WII .................................................................................................3
Smart control brings comfort - VRVII & VRV-WII ...........................................................................4
Less frequent start/stop cycle - VRVII & VRV-WII...........................................................................4
PID control................................................................................................................................................................5
Operation control of small capacity indoor units...........................................................................5
Control flow ............................................................................................................................................................5
2 Energy efficient solution
Low running costs - VRVII & VRV-WII ....................................................................................................6
Most advanced reluctance brushless DC compressor technology -
VRVII & VRV-WII....................................................................................................................................................6
HRV - Heat Reclaim Ventilation System - VRVII & VRV-WII.....................................................6
Auto restart capability - VRVII & VRV-WII ...........................................................................................6
Low operation sound level - VRVII ..........................................................................................................7
Operation range of outdoor temperature - VRVII........................................................................8
3 High reliability
Nr. 1 anti-corrosion treatment - VRVII...................................................................................................9
Double back-up function - VRVII............................................................................................................10
Duty cycling - VRVII & VRV-WII................................................................................................................10
Special oil equalising technology............................................................................................................10
4 Eco friendly
Lowest refrigerant amount in the total system - VRVII..........................................................11
Dramatic reduction in initial refrigerant charge - VRVII..........................................................11
Optimised R-410A design - VRVII & VRV-WII.................................................................................11
Less waste and improved re-cycling - VRVII ...................................................................................11
Refrigerant recovery function - VRVII & VRV-WII .......................................................................11
5 Easy and flexible design
Total room layout flexibility - VRVII & VRV-WII ............................................................................12
Complete flexibility - VRVII & VRV-WII ...............................................................................................12
Year round cooling and/or heating......................................................................................................12
Longest refrigerant piping run ................................................................................................................13
VRV Pro selection programme ................................................................................................................14
VRV Xpress............................................................................................................................................................14

• VRVII & VRV-WII features
• Systems • VRVII & VRV-WII features
2
VRVII & VRV-WII features
Table of contents
6 Simple and rapid installation
Short installation time - VRVII & VRV-WII......................................................................................... 15
Dramatic reduction in installation space........................................................................................... 15
Modular & lightweight ................................................................................................................................. 16
No structural reinforcement necessary - VRVII............................................................................. 16
Unified REFNET piping - VRVII ................................................................................................................. 17
Increased installation flexibility - VRVII............................................................................................... 17
High external static pressure : 6mm H2O - VRVII........................................................................ 17
4-way piping connection - VRVII & VRV-WII.................................................................................. 17
Downsizing refrigerant piping................................................................................................................. 18
Sequential start - VRVII & VRV-WII ....................................................................................................... 19
Self diagnosis - VRVII & VRV-WII ............................................................................................................ 19
Crosswiring check - VRVII & VRV-WII.................................................................................................. 19
Simplified wiring - VRVII & VRV-WII..................................................................................................... 19
“Super Wiring” system - VRVII & VRV-WII.........................................................................................19
4-way wiring connection - VRVII & VRV-WII.................................................................................. 20
Auto address setting function - VRVII & VRV-WII...................................................................... 20

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1
• Systems • VRVII & VRV-WII features 3
• VRVII & VRV-WII features
1 Creating maximum comfort
1-1 Inverter technology - VRVII & VRV-WII
The linear VRV system makes use of a variable Proportional Integral (PI) control system which uses refrigerant pressure sensors to give added control
over inverter and ON/OFF control compressors in order to abbreviate control steps into smaller units to provide precise control in both small and larger
areas.
This in turn enables individual control of up to 40 indoor units of different capacity and type at a ratio of 50~130 % in comparison with outdoor units
capacity. 5 HP outdoor units use inverter control compressors only.
5HP Outdoor Unit
Large Load Small
100%
24%
Inverter
Control
210Hz~52Hz
20 Steps
Compressor Capacity Control
14,16HP Outdoor Unit
Large Load Small
100%
10%
Nr. 1
Compressor
Inverter Control
Nr. 1
Compressor
Inverter Control
Nr. 1
Compressor
Inverter Control
Inverter Control
210Hz~52Hz 20 steps
Nr. 3
Compressor
100% Operation
Nr. 2
Compressor
100% Operation
Nr. 2
Compressor
100% Operation
210Hz~52Hz
+ Nr. 2 + Nr. 3
Compressor
35 Steps
Compressor Capacity Control
8,10,12HP Outdoor Unit
Large Load Small
100%
14%
Nr. 1
Compressor
Inverter Control
Nr. 1
Compressor
Inverter Control
Nr. 2
Compressor
100% Operation
210Hz~52Hz
+ Nr. 2 Compressor
29 Steps
Compressor Capacity Control

• VRVII & VRV-WII features
1
• Systems • VRVII & VRV-WII features
4
1 Creating maximum comfort
1-2 Smart control brings comfort - VRVII & VRV-WII
An electronic expansion valve, using PID control, continuously adjusts the refrigerant volume in respond to load variations of the indoor units. The VRV
system thus maintains comfortable room temperatures at a virtually constant level, without the temperature variations typical of conventional ON/OFF
control systems.
The thermostat can control stable room temperature at ±0.5°C from set point.
1-3 Less frequent start/stop cycle - VRVII & VRV-WII
• The technique adopted by Daikin, of regulating the capacity using multiple compressors clearly results in minimum switching losses and power surges
because of the overlap in capacity and frequency
• Since Daikin utilises small 5HP inverter compressors, the influence of harmonics is less than that generated by a single large compressor
• The use of multiple compressors by Daikin also ensures a 50 % standby facility
• Smaller compressors are cheaper and faster to replace
Cooling
NOTE
1 the graph shows the data, measured in a test room assuming actual heating load.
Repeats hot and cold cycles
Start-up time reduced by
about 1/3
Large temperature
difference
Inverter AC
Non inverter AC
Set point
Slow start-up
Keeps temperature stable
Smaller
temperature
difference
VRV series (Daikin PID controls)
On/off controlled air conditioner (2.5HP)
Time
Suction air temp.
Frequency
30 116 30+on 116+on
Capacity
50%
60%
55%
65%

1
• Systems • VRVII & VRV-WII features 5
• VRVII & VRV-WII features
1 Creating maximum comfort
1-4 PID control
Proportional Integral Derivative control with an automatic capacity balancing circuit:
– enables the use of lengthy piping up to 100 meters (actual length)
– consists of two control systems:
1Oil control system that controls the refrigerant oil volume to prevent it from raising or backing up in the pipes
2Refrigerant flow stabilization mechanism: prevents refrigerant drift, caused by level difference of indoor units in the same system.
1-5 Operation control of small capacity indoor units
If the operating frequency is minimal, the refrigerant pressure and outdoor temperature are detected, the number of control steps are calculated, and
capacity of outdoor unit heat exchanger (refrigerant accumulates in coils) and air flow of outdoor unit fans (controls pole change of the two fans) are
controlled.
If operating a small-capacity indoor unit, the bypass valve is controlled (ON/OFF), with capacity control being executed at a minimum of 14% for a 5HP
outdoor unit (when operating one 20-class indoor unit), or a minimum of 8% for 8 and 10HP outdoor units (when operating one 20-class indoor unit.
1-6 Control flow
Minimum Frequency
(5HP Outdoor Unit: 30Hz)
(8/10HP Outdoor Unit: 30Hz)
No
Are you operating a
small-capacity indoor unit?
Yes
Detection of Refrigerant Pressure and Outdoor
Temperature
Step Control Calculation
Bypass Valve On/Off Control
Capacity Control of Outdoor Unit
Heat Exchangers
Air Flow Control of Outdoor
Unit Fans
Deviation (difference between
sensed pressure and desired value)
No Yes
Frequency Alteration of Inverter Compressor
On/Off of ON/OFF Compressor
Outdoor Coil Capacity
Control Air Volume
Control by Outdoor
Unit Fan
Step Control
Calculation
Detection of
Refrigerant Pressure
and Outdoor
Temperature
Sampling Timer Count
Operating Pressure Detection by Pressure Sensors
Calculation of Constant for Integral Control
Total capacity Decision by Multi-Variable P-Control
Optimal Load Decision
Minimum Frequency
Every T Seconds

• VRVII & VRV-WII features
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• Systems • VRVII & VRV-WII features
6
2 Energy efficient solution
2-1 Low running costs - VRVII & VRV-WII
• VRV systems have low running costs because it permits each zone to be controlled individually. That is, only those rooms that require air conditioning
will be heated or cooled, while the system can be shut down completely in rooms where no air conditioning is required.
• VRV units have the highest COP/EER in the market in the most common operating area
2-2 Most advanced reluctance brushless DC compressor technology - VRVII & VRV-WII
The scroll compressor is driven by the newly developed motor, enabling better performance, higher enery efficiency resulting in higher energy cost
savings.
2-3 HRV - Heat Reclaim Ventilation System - VRVII & VRV-WII
• Heat and humidity are exchanged between supply and exhaust air, which
-brings outdoor air close to indoor air conditions
- recovers energy loss
- realises considerable reduction of air conditioning capacity
• The heat exchanger modulates the humidity and temperature of incoming fresh air to match indoor conditions.
• The balance achieved between indoor and outdoor ambients, enables the cooling/heating load placed on the air conditioning system to be reduced.
(heat and humidity are exchanged)
• Most energy saving solution as smaller indoor units can be selected:
-size down of indoor units down to 40 %
-payback total VAM system: ±2.5 years*
*conditions: outside cooling conditions: 30°C / outside heating conditions: - 8°C
inside cooling conditions: 24°C / inside heating conditions: 22°C
ventilation per room: 150m3/h
• Ideal modular concept to cope with the fresh air requirements
2-4 Auto restart capability - VRVII & VRV-WII
Even after exceptionally long power failures, the built-in auto restart capability ensures automatic system start up. Since the preset memory is not erased
by interruptions in power supply, no programme resetting is necessary.

2
• Systems • VRVII & VRV-WII features 7
• VRVII & VRV-WII features
2 Energy efficient solution
2-5 Low operation sound level - VRVII
• Continuous research by Daikin into reducing operation sound levels has resulted in the development of a purpose designed inverter scroll compressor
and fan.
• The new grille and fan offer low noise, high volume airflow and are housed in a compact casing together with the associated compressor
components. The use of this new technology assembly enables a 16hp unit to be housed in a single casing.
Aero spiral fan:
Bending the fan blade edge reduces turbulence, resulting in less pressure loss
Aero fitting grille:
New shape promotes spiral discharge airflow, resulting in reduced pressure loss
• Night quiet function (max. -8dBA)
During night time, sound level of the outdoor unit can be reduced for a certain period : starting time and ending time can be input
VRV-WII
Water-cooled air conditioning can be acceptable in certain critical areas in which the operating sound of air-cooled air conditioning could be a little
intrusive. This results from:
• the low operating sound level of the condensing unit
• indoor installation capabilities of the unit
• custom engineered sound level of the dry cooler
VRVII & VRV-WII
• Daikin indoor units have very low sound operation levels, down to 25 dBA.
NOTES
1 This function is available in setting at site.
2 The relationship of outdoor temperature (load) and time shown in the graph is just an example.
dB(A) Perceived loudness Sound
0 Treshold of hearing -
20 Extremely soft Rustling leaves
40 Very soft Quiet room
60 Moderately loud Normal conversation
80 Very loud City traffic noise
100 Extremely loud Symphonic orchestra
120 Threshold of feeling Jet taking off
50
8:00 12:00 16:00 20:00 0:00 4:00 8:00
50
100
Capability %
Load %
Night mode starts
58
0
external signal input
to outdoor PCB
Night-mode
Max. -8 dBa (10HP)
Night mo
d
ends
Operation
sound dBA
Daikin indoor units

• VRVII & VRV-WII features
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• Systems • VRVII & VRV-WII features
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2 Energy efficient solution
2-6 Operation range of outdoor temperature - VRVII
Standard operation down to -20°C outdoor ambient temperature
Advanced PI control of the outdoor unit enables VRVII heat recovery and Inverter cooling only/heat pump series to operate at outdoor ambients down
to -5°C in cooling mode and down to -20°C in heating mode.
VRV-WII
Wide operating range of the water-cooled units between 10 C & 45 C, both in cooling and heating.
VRV II heat pump
-20 CWB
-5 CDB
Heating
15.5 CWB
Cooling
43 CDB
50
40
30
20
10
-5
-10
-15
-20
VRVII heat recovery
-20 CWB
-5 CDB
Heating
15.5 CWB
-5 CWB
Heating
15.5 CWB
Cooling
43 CDB
50
40
30
20
10
-5
-10
-15
-20
50
40
30
20
10
0
10°C 10°C
Heating
45°C
Cooling
45°C

3
• Systems • VRVII & VRV-WII features 9
• VRVII & VRV-WII features
3 High reliability
3-1 Nr. 1 anti-corrosion treatment - VRVII
• Special anti corrosion treatment of the heat exchanger provides 5 to 6 times greater resistance against acid rain and salt corrosion. The provision of
rust proof steel sheet on the underside of the unit gives additional protection.
Improvement in corrosion resistance
Performed tests
contents of 1 cycle (7 days):
• 24 hours salt spray test SS DIN 50021
• 96 hours humidity cycle test KFW DIN 50017
• 48 hours room temperature & room humidity
testing period : 5 cycles
contents of 1 cycle (48 hours):
according to DIN50018 (0.21)
testing period : 40 cycles
Corrosion resistance rating
Non-treated Anti-corrosion treated
Salt corrosion 1 5 to 6
Acid rain 1 5 to 6
An anti-corrosion heat exchanger cutaway view
Hydrophilic film
Aluminium
Corrosion-resistant Acrylic resin
Heat exchanger
1 VDA Wechseltest
8
6
4
2
0
Corrosion resistance
Cycle
1 2 3 4 5
Daikin P.E.
Bare aluminium
2 Kesternich test (SO2)
10
9
8
7
6
5
4
3
2
1
0
Corrosion resistance
Cycle
1 2 3 4 5 6 10 20 30 40
Daikin P.E.
Bare aluminium

• VRVII & VRV-WII features
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• Systems • VRVII & VRV-WII features
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3 High reliability
3-2 Double back-up function - VRVII
In the event of a compressor malfunction, the remotely controlled or field set back-up function in the outdoor unit in question (and also between
different outdoor units) will allow emergency operation of another compressor in order to maintain 8 hour maximum interim capacity
3-3 Duty cycling - VRVII & VRV-WII
The cyclical start-up sequence of multiple outdoor unit systems equalises compressor duty and extends operating life.
3-4 Special oil equalising technology
The incorporation of this technology ensures that the optimum quantity of oil is contained in each outdoor unit module in order to maintain compressor
reliability. Automatic checks are carried out every 6 minutes on the number of compressors in operation and also to ascertain that there is enough oil to
keep them running.
Each compressor in a VRVII outdoor unit is equipped with an internal oil equalising circuit, comprising an oil separator and oil return circuit. This ensures
that the maximum quantity of oil is returned to the compressor case before entering the REFNET piping network.

4
• Systems • VRVII & VRV-WII features 11
• VRVII & VRV-WII features
4 Eco friendly
4-1 Lowest refrigerant amount in the total system - VRVII
4-2 Dramatic reduction in initial refrigerant charge - VRVII
4-3 Optimised R-410A design - VRVII & VRV-WII
Daikin Europe has achieved a quantum leap forward in commercial air conditioning technology by the introduction of its VRVII, the world’s first R-410A
operated variable refrigerant flow system. Available in cooling only, heat pump and heat recovery versions, the new system, which represents a
considerable advance over earlier VRV systems, demonstrates Daikin’s innovative application of new technology and the latest HFC refrigerants to its
VRV product programmes.
4-4 Less waste and improved re-cycling - VRVII
The lead free, soldered PCB obviates environmental contamination, whilst the re-cyclable galbarium steel bottom plate is designed to last around 6 times
longer than the traditional galvanised base.
4-5 Refrigerant recovery function - VRVII & VRV-WII
The refrigerant recovery function enables all expansion valves to be opened. In this way the refrigerant can be drained from the piping system and
stored in the receiver and the condenser.
18 HP Comparable VRF system
Total refrigerant amount in the system* 100 % 160 %
NOTE
* based on average installation
16 HP R-22
VRV-K series
R-407C
VRV-K series
R-410A
series
Refrigerant charge 100 % 85.6 % 79.5 %
Reduction
of 20.5 %

• VRVII & VRV-WII features
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• Systems • VRVII & VRV-WII features
12
5 Easy and flexible design
5-1 Total room layout flexibility - VRVII & VRV-WII
• VRVII systems are easily adaptable to changes in room layout : extra indoor units can be added to a VRV outdoor unit up to a capacity level of 130%.
• Also, since VRVII heat recovery systems offer simultaneous cooling and heating, existing indoor and outdoor units can continue to provide year round
air conditioning from their existing locations, even if office layouts are altered or extended.
5-2 Complete flexibility - VRVII & VRV-WII
•The VRVII /VRV-WII system enables different floors or even rooms to be rented to different customers, because each room has independent control of its air
conditioning.
• Thanks to inverter technology, as many as 40 indoor units (32 indoor units for VRV-WII ) with different types and capacities can be installed in one
system. This system automatically and effectively controls each unit to provide individual rooms of different sizes with a comfortable working or
living environment.
5-3 Year round cooling and/or heating
VRVII & VRV-WII
• Designed to provide simultaneous year round cooling and/or heating, VRVII heat reovery systems are modular in concept and are therefore, ideal
for use in rooms or zones that generate varying thermal loads according to building orientation or local cold or hot spots.
VRVII & VRV-WII
• It is possible for the same meeting room to give rise to differing thermal loads depending on the time of day, number of occupants present, location
and usage pattern of lighting and electronic office equipment.
VRVII & VRV-WII
• Until the advent of the VRV, a complex 4-pipe fan coil was needed to meet this requirement. The VRV however, is easier to design and install an in
its heat recovery format, can conserve energy in two or more rooms at the same time.
VRV-WII
• The colder it is outside, the warmer it needs to be indoors, which means that the capacity of the air-cooled outdoor unit drops. Water-cooled air
conditioners are not subject to this problem. The boiler ensures that sufficient enough additional heat is always available indoors.
Room layout change
Indoor unit
addition
Office
Reception room
Stock room
Office
Meeting room
Meeting room
Meeting room
Meeting room

5
• Systems • VRVII & VRV-WII features 13
• VRVII & VRV-WII features
5 Easy and flexible design
5-4 Longest refrigerant piping run
VRVII
The ability to sustain refrigerant piping in lengths up to 150m (175m equivalent), allows systems to be designed with level differences of 50m between
indoor and outdoor units and 15m between individual indoor units. Thus, even with installations in 15 storey buildings, all outdoor units can be located
at rooftop level.
VRV-WII
• The water-cooled
VRV-WII , uses water as its heat source and since there are no limitations on water piping length, is eminently suitable for application
to tall multi storey or large buildings. Considerable flexibility is available within the refrigerant circuit since up to 120m actual piping length and 50m*
(if the
VRV-WII is above the indoor units) in height can exist between the VRV-WII and indoor units. Water piping does not intrude on the occupied
spaces, so there are no leakage problems.
• * 40m if the
VRV-WII is below the indoor units.
NOTES
1 In this case the outdoor unit is located above the indoor unit. If the outdoor unit is located underneath the indoor
unit the level difference is a maximum of 40m.
Actual piping
length 150 m
Equivalent piping
length 175 m
Actual piping
length
*1
Level difference
between indoor and
outdoor units
Level difference
between indoor
units Piping length
between first
branch and furthest
indoor units
Actual piping
length 120 m
Equivalent piping
length 140 m
Actual piping length
between the VRV-WII and indoor units: 120m
(Equivalent piping length: 140m)
Water piping
Refrigerant piping
Level difference
between indoor units: 15m
Level difference between the VRV-WII
and indoor units:
50m if the VRV-WII is above
40m if the VRV-WII is below
Indoor installation
VRV-WII
Water piping length depends on the heat source equipment

• VRVII & VRV-WII features
5
• Systems • VRVII & VRV-WII features
14
5 Easy and flexible design
5-5 VRV Pro selection programme
A simple to use, Daikin Hi-VRV air conditioning computerised selection programme, designed for use with Windows 95®, Windows 98®and WindowsNT®
systems, enables consulting engineers, design and build contractors, property developers and architects etc. to plan a Daikin air conditioning project on
a step by step basis, complete with detailed drawings, bills of quantities and costs.
The programme thus enables VRV air conditioning systems to be engineered precisely and economically (without over-sizing units), thereby ensuring
optimum operating cycles and maximum energy efficiency.
Features
• The VRV Pro selection programme offers 3 separate modes to accommodate different design formats according to customer requirements. Multi
languages are possible.
1. Expert mode
Once the cooling and heating loads in the different rooms have been calculated, the software will select the most appropriate system plus an
estimate of the power consumption
2. Quick mode
Based on calculated system loads, the software will select the most appropriate system
3. Drawing mode
Selecting the indoor and outdoor units from a list enables the user to design a system in no time at all
•AutoCAD and scanned drawings can be used to help draw up a floor plan
•Piping diameters can be automatically calculated
•Indoor and outdoor units, headers and joints etc can be automatically selected
Windows95®, Windows98®and WindowsNT®are registered trademarks of Microsoft corporation.
5-6 VRV Xpress
This new super rapid response VRV selection tool is easy to understand, easy to use and enables automated piping and wiring diagrams of up to 3MB
to be transmitted via e mail. The package comes complete with single file software and update, requires no installation or drawings and is available in
multi language options.

3
6
• Systems • VRVII & VRV-WII features 15
• VRVII & VRV-WII features
6 Simple and rapid installation
6-1 Short installation time - VRVII & VRV-WII
• Thanks to small bore refrigerant pipes and REFNET piping options, the VRVII/VRV-WII piping system can be installed very easily and quickly.
• Installation of the VRVII/VRV-WII system can also be implemented floor by floor, so that sections of the building can be put into use very quickly, or
enabling the air conditioning system to be commissioned and operated in stages, rather than on final completion of the project.
6-2 Dramatic reduction in installation space
VRVII
VRVII features a dramatic reduction in installation space - for example, the 16hp outdoor unit is housed in a single casing outdoor unit, providing a 50 %
reduction in required installation space.
VRV-WII
The adoption of a new water heat exchanger and optimization of the refrigerant control circuit has resulted in the industry’s most compact and
lightweight design. The unit weight of 150kg and height of 1,000mm makes installation easy. Stacked configuration is also possible, contributing further
to space savings.
Installation space (16 HP)
3.56 m2→1.88 m2
RSXYP
➧
Approx.
50 %
reduction
Stacked configuration is possible.
3200mm
or higher
Ceiling height)
(Floor level)
(100-300mm)

• VRVII & VRV-WII features
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• Systems • VRVII & VRV-WII features
16
6 Simple and rapid installation
6-3 Modular & lightweight
• Modular design enables units to be joined together in rows with an outstanding degree of uniformity.
• The design of the outdoor units is sufficiently compact to allow them to be taken up to the top of a building in a commercial elevator, overcoming
site transportation problem, particularly when outdoor units need to be installed on each floor.
6-4 No structural reinforcement necessary - VRVII
• The galbarium steel allows the use of block foundations. Earlier VRVK and L systems required full beam foundations.
• Thanks to the lightweight and vibration-free construction of the outdoor units, floors do not need to be reinforced, reducing the overall cost of the
building.
10HP
WEIGHT REDUCTION 100 % 84 % 58 %
Reduction
of 42%

6
• Systems • VRVII & VRV-WII features 17
• VRVII & VRV-WII features
6 Simple and rapid installation
6-5 Unified REFNET piping - VRVII
• The unified Daikin REFNET piping system is especially designed for simple installation
• The use of REFNET piping in combination with electronic expansion valves, results in a dramatic reduction in imbalance in refrigerant flowing between
indoor units, despite the small diameter of the piping.
• REFNET joints and headers (both accessories) can cut down on installation work and increase system reliability.
• Compared to regular T-joints, where refrigerant distribution is far from optimal, the Daikin REFNET joints have specifically been designed to optimise
refrigerant flow.
6-6 Increased installation flexibility - VRVII
Outdoor units can be installed far back from former location.
6-7 High external static pressure : 6mm H2O - VRVII
Daikin now offers high external static pressure as standard to meet requirements of indoor installation.
6-8 4-way piping connection - VRVII & VRV-WII
VRVII series not only offer the possibility to run piping from the front, but also from the left, right or bottom, thus providing greater freedom of layout.
REFNET joint Attached insulators for REFNET joint REFNET header Attached insulators for REFNET header REFNET joint T-joint
DuctDuct
current
Front
Left
Bottom
Right

• VRVII & VRV-WII features
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• Systems • VRVII & VRV-WII features
18
6 Simple and rapid installation
6-9 Downsizing refrigerant piping
• Reduced piping diameters
Use of high efficiency R-410A enables the VRVII to operate on a smaller refrigerant charge to be used, leading to a reduction in liquid and gas pipe diameters.
• Reduced piping costs thanks to modular design
Smaller diameter liquid and gas piping contributes to a reduction in installation space and installation costs.
based on a 240HP installation
VRV
0.51 m20.29 m2
VRVII
1,700 x 300 950 x 300
System
Outdoor unit
Standard VRV System
Outdoor unit Indoor units (max. 16 units)
Indoor units (max. 40 units)
Around 30% reduction
in installation costs for
refrigerant piping.
System
R-410A
H2O
Indoor units (max. 32 units)

6
• Systems • VRVII & VRV-WII features 19
• VRVII & VRV-WII features
6 Simple and rapid installation
6-10 Sequential start - VRVII & VRV-WII
Up to 3 outdoor units can be connected to 1 power supply and can be turned on sequentially. This allows the number of breakers and their capacities
to remain small and simplifies wiring (for models of 10Hp or less).
6-11 Self diagnosis - VRVII & VRV-WII
Detects malfunctions in major locations of the system and displays the type of malfunction and location, which in turn allows servicing and maintenance
to be performed more efficiently.
6-12 Crosswiring check - VRVII & VRV-WII
The cross wiring check facility available on the VRVII is the first of its type in the industy to warn operatives of connection errors in interunit wiring and
piping. This function identifies and alerts system errors by means of on/off LEDs on the outdoor unit’s PC boards.
6-13 Simplified wiring - VRVII & VRV-WII
• A simple 2-wire non-shielded multiplex transmission system links each outdoor unit to multiple indoor units using one 2-core wire, thus simplifying
the wiring operation.
• Furthermore, outdoor units have power connection outlets on side and front, resulting in easier installation and maintenance and saving space when
rows of units are connected together.
6-14 “Super Wiring” system - VRVII & VRV-WII
• A Super Wiring system is used to enable the shared use of wiring between indoor units, outdoor units and the centralised remote control.
• This system makes it easy for the user to retrofit the existing system with a centralised remote control, simply by connecting it to the outdoor units.
• Thanks to a non polarity wiring system, incorrect connections become impossible and installation time is reduced.