Mitsubishi Electric CITY MULTI PUMY-P200YKM3, Руководство по обслуживанию

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OCH791 _107
12 REFRIGERANT PIPING TASKS
12-1. Refrigerant piping system
Refer to installation manual “Pipe length and height difference” for refrigerant piping system.
12-2. PRECAUTIONS AGAINST REFRIGERANT LEAKAGE
12-2-1. Introduction
R410A refrigerant of this air conditioner is non-toxic and non-flammable but leaking of large amount from an indoor unit
into the room where the unit is installed may be deleterious. To prevent possible injury, the rooms should be large enough
to keep the R410A concentration specified by ISO 5149-1 as follows.
■ Maximum concentration of R410A: 0.44 kg/m 3 [0.027 lbs/ft 3 ] (ISO 5149-1).
Maximum refrigerant concentration of R410A of a room is 0.44kg/m
3
[0.027 lbs/ft
3
] in accordance with ISO 5149-1.
To facilitate calculation, the maximum concentration is expressed in units of kg/m
3
[lbs/ft
3
] (kg [lbs] of R410A per m
3
[ft
3
])
Indoor unit
All refrigerant of this system will leak out to this
room if there is leakage at this indoor unit.
Direction of refrigerant flow
Outdoor unit
Branch box
12-2-2. Confirming procedure of R410A concentration
Follow 1 to 3 to confirm the R410A concentration and take appropriate treatment, if necessary.
1. Calculate total refrigerant amount by each refrigerant system. Total refrigerant amount is precharged refrigerant be-
fore shipment plus additional charged amount at field installation.
Note:
• When the air conditioning system consists of several independent refrigerant system, figure out the total refrigerant
amount by each independent refrigerant system.
2. Calculate room volumes (m 3 ) and find the room with the smallest volume.
The part with represents the room with the smallest volume.
2-1. Situation in which there are no partitions
Indoor unit
Branch box
Outdoor unit
2-2. There are partitions, but there are openings that allow the effective mixing of air.
Indoor unit
Branch box
Opening
Wall
Outdoor unit
Situation in which there are no door openings or
in which there are openings above and below
doors that occupy at least 0.15% of the floor area
2-3. If the smallest room has mechanical ventilation apparatus that is linked to a household gas detection and alarm
device, the calculations should be performed for the second smallest room.
Indoor unit
The
smallest
room
The second
smallest
room
Outdoor unit
Ventilation apparatus
Branch box
3. Use the results of calculations 1 and 2 to calculate the refrigerant concentration.
Total refrigerant in the refrigerating unit (kg [lbs])
Maximum concentration (kg/m
3
[lbs/ft
3
])*
The smallest room in which an indoor
unit has been installed (m
3
[ft
3
])
≤
*Maximum concentration of R410A: 0.44kg/m
3
[0.027lbs/ft
3
]
3-1. If the calculation results do not exceed the maximum concentration, perform the same calculation for larger rooms
until it has been determined that nowhere exceeds the maximum concentration.