6 Installation
Installer and user reference guide
21
5TMV1B
VRV IV-S system air conditioner
4P404224-1 – 2015.03
▪ Reinforce the insulation on the refrigerant piping according to the
installation environment.
Ambient
temperature
Humidity
Minimum thickness
≤30°C
75% to 80% RH
15 mm
>30°C
≥80% RH
20 mm
Condensation might form on the surface of the insulation.
▪ If there is a possibility that condensation on the stop valve might
drip down into the indoor unit through gaps in the insulation and
piping because the outdoor unit is located higher than the indoor
unit, this must be prevented by sealing up the connections. See
below figure.
b
a
a
Insulation material
b
Caulking etc.
6.7
Charging refrigerant
6.7.1
About charging refrigerant
The outdoor unit is factory charged with refrigerant, but depending
on the field piping you have to charge additional refrigerant.
Before charging refrigerant
Make sure the outdoor unit's
external
refrigerant piping is checked
(leak test, vacuum drying).
Typical workflow
Charging additional refrigerant typically consists of the following
stages:
1
Determining how much you have to charge additionally.
2
Charging additional refrigerant (pre-charging and/or charging).
3
Filling in the fluorinated greenhouse gases label, and fixing it to
the inside of the outdoor unit.
6.7.2
Precautions when charging refrigerant
INFORMATION
Also read the precautions and requirements in the
following chapters:
▪ General safety precautions
▪ Preparation
WARNING
▪ Only use R410A as refrigerant. Other substances may
cause explosions and accidents.
▪ R410A contains fluorinated greenhouse gases. Its
global warming potential value is 2087.5. Do NOT vent
these gases into the atmosphere.
▪ When charging refrigerant, always use protective
gloves and safety glasses.
NOTICE
If the power of some units is turned off, the charging
procedure cannot be finished properly.
NOTICE
Be sure to turn on the power 6 hours before operation in
order to have power running to the crankcase heater and
to protect the compressor.
NOTICE
If operation is performed within 12 minutes after the indoor
and outdoor units are turned on, the compressor will not
operate before the communication is established in a
correct way between outdoor unit(s) and indoor units.
NOTICE
Before starting charging procedures, check if the 7‑LEDs
display is as normal (see
"7.2.4 To access mode 1 or 2" on
page 27
), and there is no malfunction code on the user
interface of the indoor unit. If a malfunction code is
present, see
"11.3 Solving problems based on error
codes" on page 36
.
NOTICE
Make sure all connected indoor units are recognised
(setting [1‑5]).
NOTICE
Close the front panel before any refrigerant charge
operation is executed. Without the front panel attached the
unit cannot judge correctly whether it is operating properly
or not.
NOTICE
In case of maintenance and the system (outdoor unit+field
indoor units) does not contain any refrigerant any
more (e.g., after refrigerant reclaim operation), the unit has
to be charged with its original amount of refrigerant (refer
to the nameplate on the unit) and the determined additional
refrigerant amount.
6.7.3
To determine the additional refrigerant
amount
INFORMATION
For final charge adjustment in a test laboratory, contact
your dealer.
Additional refrigerant to be charged=R (kg). R should be rounded off
in units of 0.1 kg.
R=[(X
1
×
Ø9.5
)×0.059+(X
2
×
Ø6.4
)×0.022]
X
1...2
=Total length (m) of liquid piping size at
Øa
INFORMATION
Piping length is considered the distance from the outdoor
unit to the farthest indoor unit.
When using metric piping, please take into account following table
concerning the weight factor to be allocated. It should be substituted
in the formula for R.
Inch piping
Metric piping
size (Ø) (mm)
Weight factor
size (Ø) (mm)
Weight factor
6.4
0.022
6
0.018
9.5
0.059
10
0.065
When selecting indoor unit, following table with connection ratio
limitation has to be respected. More detailed information can be
found in technical engineering data.
