12 Special requirements for R32 units
Installation and operation manual
19
BS4~12A14AJV1B
VRV 5 branch selector unit
4P670163-1 – 2022.02
Multiple BS units in series – one extraction fan
In this configuration, multiple BS units are connected in series to a
single extraction fan. The air flows through every BS unit to the
extraction fan. In case of a refrigerant leak in any BS unit, the
dampers of all BS units will open and allow air evacuation to the
extraction fan.
a
a
a
d
b
c
c
b
b
a
BS unit
b
Ductwork
c
EKBSDCK
d
Extraction fan
It is sufficient to connect the extraction fan circuit to only 1 BS unit of
the cluster (see
"15.5 To connect the external outputs"
34]). It is
not allowed to have BS units in the same series cluster that belong
to different outdoor unit systems.
Example
a
a
a
f
c
e
c
e
d
e
A
e
a
b
b
f
d
e
c
e
d
e
A
e
B
e
a
BS unit belonging to outdoor unit A
b
BS unit belonging to outdoor unit B
c
Extraction fan output terminal – NOT connected
d
Extraction fan output terminal – connected
e
Transmission wiring terminal
f
Extraction fan
A
Outdoor unit A
B
Outdoor unit B
Transmission wiring
Extraction fan output wiring
Allowed
NOT allowed
The option kit EKBSDCK is required each time a duct is connected
to the air inlet (damper side) of the BS unit.
An online tool (
) is available to find the required pressure
capacity for selecting the correct fan size. Only use this online tool
for the calculation.
BS unit test run
Before BS unit operation, it is required to perform a test run that
simulates a refrigerant leak. See
38] for
more details.
Field settings
Multiple BS units in series – one extraction fan
Code
Description
Value
[2-0]
Cluster indication
1: enable
[2-1]
Cluster number
#
(a)
[2-2]
Cluster configuration
1: series
[2-4]
Safety measures
1 (default): enable
[2-7]
Ventilated enclosure
1 (default): enable
(a)
Assign a unique cluster number to each cluster in the system. All
BS units in the same cluster MUST have the same cluster
number.
Note:
Some field settings need to be made on all main PCB's (A1P,
A2P and A3P) of the same BS unit. For more information, see
34].
12.5
Combinations of ventilated
enclosure configurations
It is possible to combine different ventilated enclosure configurations
(clusters) in the same system. To do this, assign a unique cluster
value to each cluster. All the BS units in the same cluster need to be
assigned the same cluster number.
Example
a
d
b
b
b
d
d
e
e
c
c
c
e
a
Outdoor unit
b
BS unit belonging to cluster 1
c
BS unit belonging to cluster 2
d
BS unit belonging to cluster 3
e
Extraction fan
Transmission wiring
Field settings
Code
Description
Value
Cluster
1
2
3
[2-0]
Cluster indication
1: enable
[2-1]
Cluster number
1
2
3
[2-2]
Cluster configuration
0 (default): parallel 1: series
[2-4]
Safety measures
1 (default): enable
[2-7]
Ventilated enclosure
1 (default): enable
Note:
Some field settings need to be made on all main PCB's (A1P,
A2P and A3P) of the same BS unit. For more information, see
34].
Example
It is not allowed to combine series and parallel configurations within
the same cluster.
a
B
A
a
a
b
a
BS unit
b
Extraction fan
A
Parallel configuration
B
Series configuration
NOT allowed
