Caution For Refrigerant Leaks - Daikin VRV II RX5MY1 Installation Manual

9.

CAUTION FOR REFRIGERANT LEAKS

(Points to note in connection with refrigerant leaks)
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 R22 as
refrigerant. R22 itself is an entirely safe non-toxic, non-combustible
refrigerant. Nevertheless care must be taken to ensure that air con-
ditioning 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.
Maximum concentration level
The maximum charge of refrigerant and the calculation of the maxi-
mum 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
kg of the refrigerant gas in 1m volume of the occupied space).
Compliance to the local applicable regulations and standards for the
maximum allowable concentration level is required.
In Japan the maximum allowed concentration level of refrigerant to a
humanly space for R22 is limited to 0.3 kg/m
1. direction of the refrigerant flow
2. room where refrigerant leak has occurred (outflow of all
the refrigerant from the system)
Pay a special attention to the place, such as a basement, etc.
where refrigerant can stay, since refrigerant is heavier than air.
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.
amount of refriger- additional charging
+
ant in a single unit amount (amount of
system (amount of refrigerant added
refrigerant with locally in accordance
which the system with the length or
is charged before diameter of the refrig-
leaving the factory) erant piping)
Note
• Where a single refrigerant facility is divided into 2 entirely inde-
pendent refrigerant systems then use the amount of refrigerant
with which each separate system is charged.
2.
Calculate the smallest room volume (m
Incase like the following, calculate the volume of (A), (B) as a sin-
gle room or as the smallest room.
A.
Where there are no smaller room divisions
English
3
( the weight in
3
.
1
2
total amount
=
of refriger-
ant (kg) in
the system
3
)
B.
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 calcu-
lations in steps 1 and 2 above.
total volume of refrigerant in the
refrigerant system
3
size (m ) of smallest room in which
there is an indoor unit installed
If the result of the above calculation exceeds the maximum con-
centration level then make similar calculations for the second then
third smallest room and so until the result falls short of the maxi-
mum concentration.
4.
Dealing with the situations where the result exceeds the maxi-
mum concentration level.
Where the installation of a facility results in a concentration in
excess of the maximum concentration level then it will be neces-
sary to revise the system.
Please consult your Daikin supplier.
1
2
≤
maximum concen-
3
tration level (kg/m )
16