Warnings On Refrigerant Leakage; Concentration Limit Check; Concentration Limit - Toshiba Carrier MCY-MAP0367HS-UL Installation Manual

Warnings on refrigerant leakage

Concentration Limit Check

The room in which the air conditioner is to be
installed requires a design that in the event of a
refrigerant gas leak, its concentration will not exceed
a set limit.
The refrigerant R410A which is used in the air
conditioner is safe, without the toxicity or combustibility
of ammonia, and is not restricted by laws to be imposed
which protect the ozone layer. However, since it contains
more than air, it poses the risk of suffocation if its
concentration should rise excessively. Suffocation from
leakage of R410A is almost non-existent. With the recent
increase in the number of high concentration buildings,
however, the installation of multi air conditioner systems
is on the increase because of the need for effective use
of floor space, individual control, energy conservation by
curtailing heat and carrying power etc.
Most importantly, the multi air conditioner system is able
to replenish a large amount of refrigerant compared with
conventional individual air conditioners. If a single unit of
the multi conditioner system is to be installed in a small
room, select a suitable model and installation procedure
so that if the refrigerant accidentally leaks out, its
concentration does not reach the limit (and in the event
of an emergency, measures can be made before injury
can occur).
In a room where the concentration may exceed the limit,
create an opening with adjacent rooms, or install
mechanical ventilation combined with a gas leak
detection device.
Use the following calculation to determine the correct
amount.
Total amount of refrigerant (lbs (kg))
Min. volume of the indoor unit installed room (ft
3
≤ Concentration limit (lbs/ft
(kg/m

Concentration limit

Compliance to the local applicable regulations and
standards for the concentration limit is required.
NOTE 1 :
If there are 2 or more refrigerating systems in a single
refrigerating device, the amounts of refrigerant should be
as charged in each independent device
.
Outdoor unit
e.g.,
e.g.,
charged amount
charged amount
(22 lbs (10 kg))
(33 lbs (15 kg))
Room A Room B Room C Room D Room E Room F
Indoor unit
For the amount of charge in this example:
The possible amount of leaked refrigerant gas in
rooms A, B and C is 22 lbs (10 kg).
The possible amount of leaked refrigerant gas in
rooms D, E and F is 33 lbs (15 kg).
EN-53
Important
NOTE 2 :
The standards for minimum room volume are as follows.
(1) No partition (shaded portion)
(2) When there is an effective opening with the adjacent
room for ventilation of leaking refrigerant gas
(opening without a door, or an opening 0.15% or
larger than the respective floor spaces at the top or
bottom of the door).
(3) If an indoor unit is installed in each partitioned room
and the refrigerant piping is interconnected, the
smallest room becomes the object. However when a
mechanical ventilation is installed interlocked with a
gas leakage detector in the smallest room where the
density limit is exceeded, the volume of the next
smallest room becomes the object.
Very
3 3
(m )) small
Small Medium
room
3
))
room room
Mechanical ventilation device - Gas leak detector
– 27 –
Outdoor unit
Refrigerant piping
Indoor unit
Refrigerant piping
Outdoor unit
Indoor unit
Large room
Installation Manual
EN-54