2 Specific installer safety instructions
Installation and operation manual
7
EKVDX32~100A2VEB
VRV system air conditioner
4P555815-1A – 2021.08
2.1.2
To determine the charge limitations
Overview
R32 charge limitations
Case 1: VAM+EKVDX and indoor unit
Lowest underground floor +
other floors
Case 2: VAM+EKVDX only
Other floors only
Lowest underground floor +
other floors
Other floors only
For A2: see
installation and
operation manual of
outdoor unit
For A1 and A2: see
installation and
operation manual of
outdoor unit
For A3: use
curve (b)
For A3: use
curve (a)
For A4: use curve (a)
For A4: use curve (b)
Of all applicable scenarios, choose the LOWEST refrigerant charge value
Graph and table for EKVDX
When total floor area A
3
is determined, use the graph or table (see
2] at the beginning of this manual) to determine the total
refrigerant charge limit in the system. For A
1
and A
2
, use the graph
or table from the outdoor unit installation manual.
m
Total refrigerant charge limit in the system
A
tot
Total room area
(a)
All other floors (=All other floors)
(b)
Lowest underground floor (=Lowest underground floor)
m
Total refrigerant charge limit in the system
A
tot
Total room area
(a)
All other floors (=All other floors)
(b)
Lowest underground floor (=Lowest underground floor)
Note:
When multiple outdoor units are servicing the same space,
use calculations on the room area based on the outdoor unit with the
largest refrigerant charge.
Note:
The factory charge depends on the outdoor unit in the system.
The examples used below consider a VRV 5-S R32 outdoor unit.
Note:
Make sure the total refrigerant charge amount is lower than:
▪ 15.96 kg x the total number of connected indoor units and EKVDX
units.
▪ 63.84 kg.
Case 1: VAM+EKVDX and indoor unit(s) combined
Step 1
– determine:
▪ A
1
– the area of the smallest room in the lowest underground floor
in which an indoor unit is present (if applicable). See outdoor unit
installation manual.
▪ A
2
– the area of the smallest room not in the lowest underground
floor, in which an indoor unit is present. See outdoor unit
installation manual.
▪ A
3
– the total area of all the rooms which the EKVDX is
discharging air into. See
Note:
The EKVDX can be discharging into the same room as a
normal indoor unit. The area of this room must also be taken into
account for A
3
.
Note:
For VAM+EKVDX, only consider rooms that are
continuously served. E.g. In case of zonal dampers in the duct
between EKVDX and a room, this room cannot be considered as
part of the total room area. Only exception are zonal dampers only
used for fire safety.
Use A
1
, A
2
and A
3
in the following steps to determine the maximum
allowable total charge of the system.
Step 2
– see the installation manual of the outdoor unit for choosing
the correct curve depending on the installation height of the indoor
unit. For EKVDX units, installation height should always be ≥2.2 m.
Step 3
– in case there are underground floors, determine the
maximum allowable charge limit in the system for each area (A
1
, A
2
and A
3
):
▪ For the room with the smallest area containing an indoor unit not
on the lowest underground floor/on the lowest underground floor:
see the outdoor unit installation manual on R32 charge limitations.
▪ For the total room area for the VAM+EKVDX system when it
contains:
▪ no room in the lowest underground floor, refer to curve (a).
▪ at least one room in the lowest underground floor, refer to curve
(b).
Once the maximum allowable charge has been calculated for all
applicable scenarios, use the lowest value as the upper limit.
