Installation and operation manual
42
10T8Y1B
VRV-W IV System Air Conditioner
4P399208-1 – 2015.01
18.3. Check of normal operation
After the check operation is completed, operate the unit normally.
(Heating is not possible if the outdoor temperature is 24°C or higher.)
Check the below items.
Make sure the indoor and outdoor units are operating normally
(If a knocking sound can be heard in the liquid compression of
the compressor, stop the unit immediately and then energize the
heater for a sufficient length of time before restarting the
operation.)
Run each indoor unit one at a time and make sure the
corresponding outdoor unit is also running.
Check if cold (or hot) air is coming out of the indoor unit.
Press the fan direction and fan strength buttons on the indoor
unit to check if they operate properly.
19. Caution for refrigerant leaks
Points to note in connection with refrigerant leaks
19.1. Introduction
The installer and system specialist shall secure safety against
leakage according to local regulations or standards. The following
standards may be applicable if local regulations are not available.
The VRV System, like other air conditioning systems, uses R410A as
refrigerant. R410A itself is an entirely safe non-toxic,
non-combustible refrigerant. Nevertheless care must be taken to
ensure that air conditioning facilities are installed in a room which is
sufficiently large. This assures that the maximum concentration level
of refrigerant gas is not exceeded, in the unlikely event of major leak
in the system and this in accordance to the local applicable
regulations and standards.
19.2. Maximum concentration level
The maximum charge of refrigerant and the calculation of the
maximum concentration of refrigerant is directly related to the
humanly occupied space in to which it could leak.
The unit of measurement of the concentration is kg/m
3
(the weight in
kg of the refrigerant gas in 1 m
3
volume of the occupied space).
Compliance to the local applicable regulations and standards for the
maximum allowable concentration level is required.
In Australia the maximum allowed concentration level of refrigerant to
a humanly space is limited to 0.35 kg/m
3
for R407C and 0.44 kg/m
3
for R410A.
1
Direction of the refrigerant flow
2
Room where refrigerant leak has occurred (outflow of all
the refrigerant from the system)
Pay special attention to places, such as a basement, etc., where
refrigerant can stay, since refrigerant is heavier than air.
19.3. Procedure for checking maximum concentration
Check the maximum concentration level in accordance with steps 1
to 4 below and take whatever action is necessary to comply.
1.
Calculate the amount of refrigerant (kg) charged to each system
separately.
2.
Calculate the smallest room volume (m
3
)
In the following cases, calculate the volume of (A), (B) as a
single room or as the smallest room.
Where there are no smaller room divisions
Where there is a room division but there is an opening
between the rooms sufficiently large to permit a free flow of
air back and forth.
1
Opening between rooms
2
Partition
(Where there is an opening without a door or where there are
openings above and below the door which are each
equivalent in size to 0.15% or more of the floor area.)
3.
Calculating the refrigerant density using the results of the
calculations in steps 1 and 2 above.
If the result of the above calculation exceeds the maximum
concentration level then make similar calculations for the second
then third smallest room and so until the result falls short of the
maximum concentration.
4.
Dealing with the situations where the result exceeds the
maximum concentration level.
Where the installation of a facility results in a concentration in
excess of the maximum concentration level then it will be
necessary to revise the system. Please consult your Daikin
supplier.
2
1
amount of refrigerant
in a single unit system
(amount of refrigerant
with which the system
is charged before
leaving the factory)
+
additional charging
amount (amount of
refrigerant added locally
in accordance with the
length or diameter of the
refrigerant piping)
=
total amount of
refrigerant (kg)
in the system
NOTICE
Where a single refrigerant facility is divided into 2 entirely
independent refrigerant systems, use the amount of
refrigerant with which each separate system is charged.
total volume of refrigerant in the
refrigerant system
≤
maximum concentration
level (kg/m
3
)
size (m
3
) of smallest room in which there
is an indoor unit installed
1
2
