Daikin VRV 5-S Series - To Determine the Charge Limit

16 | Special requirements for R32 units
Installer and user reference guide
65
RXYSA4~6A7V/Y1B
VRV 5-S system air conditioner
4P600330-1D – 2023.02
16.3 To determine the charge limit
Step 1 – In order to derive the total refrigerant charge limit in the system,
determine the area:
▪ of the rooms where an indoor unit is installed.
▪ AND of the rooms served by a ducted indoor unit installed in a different room.
The room area can be determined by projecting the walls, doors and partitions to
the floor and calculate the enclosed area. The area of the smallest room being
served by the system is used in the next step to determine the maximum allowable
total charge of the system.
Spaces connected by only false ceilings, ductwork, or similar connections shall not
be considered a single space.
If the partition between two rooms on the same floor meets certain requirements,
then the rooms are considered as one room and the areas of the rooms may be
added up. In this way it is possible to increase the A
min
value used to calculate the
maximum allowed charge.
One of the following two requirements must be met to add up room areas:
▪ Rooms on the same floor that are connected with a permanent opening that
extends to the floor and is intended for people to walk through can be
considered as one room.
▪ Rooms on the same floor connected with openings that fulfil following
requirements can be considered as a single room. The opening must consist out
of two parts to allow for air circulation.
A
nvmin
≥ 20 mm
≥ 50% A
nvmin
≤ 100 mm
1500
mm
300
mm
200
mm
≥ 20 mm
A
nvmin
Minimal natural ventilation area
For the lower opening:
- It is not an opening to the outside
- The opening cannot be closed
- The opening must be ≥0.012m² (A
nvmin
)
- The area of any openings above 300mm from the floor does not count when
determining A
nvmin
- At least 50% of A
nvmin
is less than 200mm above the floor
- The bottom of the lower opening is ≤100mm from the floor
- The height of the opening is ≥20mm