
8.6 MAXIMUM PERMISSIBLE CONCENTRATION OF HYDROFLUOROCARBON (HCF)
REFRIGERANT
• Caution on Refrigerant Leakage
Specifiers/installers have responsibility to follow local codes
and regulation which specify safety requirements against
refrigerant leakage
• Maximum Permissible Concentration of HCFC/HFC Gas
The refrigerant R410A, charged in the SET-FREE system,
is an incombustible and non-toxic gas. However, if leakage
occurs and gas fills a room, it may cause suffocation.
The maximum permissible concentration of HCFC/HFC gas,
R410A in air is 0.44 kg/m³, according to EN378-1.
Therefore, some effective measure must be taken to lower
the R410A concentration in air below 0.44 kg/m³, in case of
leakage.
• Calculation of Refrigerant Concentration
1
Calculate the total quantity of refrigerant R (kg) charged in
the system connecting all the indoor units of rooms to be
air-conditioned.
2
Calculate the room Volume V (m³) of each room.
3
Calculate the refrigerant concentration C (kg/m³) of the room
according to the following equation:
R
V =C
R: Total quantity of charged refrigerant (kg)
V: Room volume (m
3
)
C: Refrigerant concentration 0.44 kg/m
3
for R410A
9 DRAIN PIPING
Outdoor Unit Drain-Kit (DBS-26) (Optional
Accessory)
In the case that drain water from the heat exchanger of the
outdoor unit is required to be collected, use the Drain Kit.
However, it is not recommended to use it in a snow fall area. If
the drain water is required to be collected completely, provide a
field-supplied drain pan under the outdoor unit.
Ø32
43 mm
Outdoor unit
HP
Drain kit
quantity
(units)
8 to 12 HP
DBS-26 x 2
10 ELECTRICAL WIRING
!
C A U T I O N
• Turn OFF the main power switch of the indoor unit and the outdoor
unit and wait for more than 3 minutes before electrical wiring work or
a periodical check is performed.
• Check to ensure that the indoor fan and the outdoor fan have stopped
before electrical wiring work or a periodical check is performed.
• Protect the wires, electrical parts, etc. from rats or other small animals.
If not protected, rats may gnaw at unprotected parts and which may
lead to a fire.
• Avoid the wirings from touching the refrigerant pipes, plate edges and
electrical parts inside the unit. If not do, the wires will be damaged
and at the worst, a fire will occur.
• Use a medium sensing speed type ELB (Electric Leakage Breaker,
activation speed of 0.1 sec. or less). If not used, it will cause an
electric shock or a fire.
• Fix the cables securely. External forces on the terminals could lead
to a fire.
• Check the item below before turning ON the main switch.In case that
the power source for outdoor unit is 415V (nominal voltage), change
CN2 (connector) to CN1 of transformer (TF) in the electrical control
box as shown in the figure below.
Connector
for 220V
Connector
for 240V
• Tightly secure the power source cable using the cord clamp inside
the unit.
?
N O T E
Fix the rubber bushes with adhesive when conduit tubes to the outdoor
unit are not used.
DRAIN PIPING
PMML0390B REV.0 - 11/2015 - P5416649
16