17 Commissioning
Installation and operation manual
39
BS4~12A14AJV1B
VRV 5 branch selector unit
4P670163-1 – 2022.02
NOTICE
It is very important that all refrigerant piping work is done
before the units (outdoor, BS or indoor) are powered on.
When the units are powered on, the expansion valves will
initialise. This means that the valves will close.
If any part of the system has already been powered on,
setting [2-21] on the outdoor unit has to be activated to
open the expansion valves.
17.1.2
About airflow requirements
When a ventilated enclosure is required, the following requirements
apply:
▪ pressure inside the BS unit has to be more than 20 Pa below the
ambient pressure,
▪ minimum airflow rate:
Model
Minimum airflow rate [m³/h]
BS4A
90
BS6~8A
87
BS10~12A
77
Example
A BS12A unit with an airflow rate during the test run of 115 m³/h.
The pressure drop graph shows that this results in an internal
pressure which is 42.9 Pa below the ambient pressure. Both
requirements are met if:
▪ The pressure inside the BS unit is more than 20 Pa below the
ambient pressure (42.9 Pa).
▪ The airflow rate is higher than 77 m³/h (115 m³/h).
0
-100
-150
-200
-250
-300
0
50
100
150
200
250
300
Y
X
115
-42.9
-50
X
Airflow rate [m³/h]
Y
Internal pressure below ambient pressure [Pa]
See the latest version of the technical engineering data for the BS
unit's pressure drop curves.
17.1.3
About measuring the airflow rate
It is up to the installer to measure the airflow rate and provide correct
data. We advise two ways in the sections below, but the installer is
entirely free on how to perform the measurement.
About measuring with a vane anemometer
▪ Where: Measure the airflow rate at the air inlet (damper) of the BS
unit.
▪ Tip: Use the duct connection kit (EKBSDCK) and an anemometer
with a funnel to conduct the entire airflow through the
anemometer.
▪ Postrequisite: Remove the kit once the measurement is finished.
b
a
a
Vane anemometer
b
Duct connection kit (EKBSDCK)
About measuring with a hot wire probe anemometer
▪ Attention: In case you need to drill holes in the ducting, choose a
location without thermal insulation.
▪ Where: Measure the airflow rate in the duct connected to the air
outlet of the BS unit.
▪ Postrequisite: Close the holes properly once the measurement is
finished.
a
d
b
c
a
BS unit
b
Air outlet duct
c
Direction airflow
d
Hot wire probe anemometer
17.1.4
Prerequisite checklist
Check the following items before starting the BS unit test run.
You read the complete installation and operation
instructions, as described in the
installer and user
reference guide
.
The
BS unit
is properly mounted.
The
field wiring
has been carried out according to the
instructions described in this document, according to the
wiring diagram and according to the applicable legislation.
Make sure
drain piping
is properly installed, insulated
and drainage flows smoothly. Check for water leaks.
Possible consequence:
Condensate water might drip.
There are NO
missing phases
or
reversed phases
.
The system is properly
earthed
and the earth terminals
are tightened.
The
fuses
or locally installed protection devices are
installed according to this document, and have NOT been
bypassed.
The
power supply voltage
matches the voltage on the
identification label of the unit.
There are NO
loose connections
or damaged electrical
components in the switch box.
In case no safety measures are required, the following
measures are correctly applied:
▪ No safety measures are attached.
▪ The correct field settings are made.
