Mitsubishi Electric CITY MULTI PUMY-SP140YKM User Manual

136
OCH668B
10-3. PRECAUTIONS AGAINST REFRIGERANT LEAKAGE
Indoor unit
The smallest
room
The second
smallest room
Outdoor unit
Ventilation apparatus
Branch box
Indoor unit
Branch box
Opening
Wall
Outdoor unit
(Situation in which there
are no door openings or
in which there are open-
ings above and below
doors that occupy at
least 0.15% of the floor
area)
Indoor unit
Branch box
Outdoor unit
10-3-1. 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.
Note:
Whensinglerefrigerationsystemconsistsofseveralinde-
pendentrefrigerationcircuit,figureoutthetotalrefrigerant
amountbyeachindependentrefrigerantcircuit.
Follow(1)to(3)toconfirmtheR410Aconcentrationandtakeappropriatetreatment,ifnecessary.
(1) Calculate total refrigerant amount by each refrig-
erant system. Total refrigerant amount is pre-
charged refrigerant at ex-factory plus additional
charged amount at field installation.
(2) Calculate room volumes (m
3
) and find the room with the smallest volume
Thepartwithrepresentstheroomwiththesmallestvolume.
Ifthecalculationresultsdonotexceedthemaximumcon-
centration,performthesamecalculationsforthelargersec-
ond and third room, etc., until it has been determined that
nowherethemaximumconcentrationwillbeexceeded.
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
Maximumconcentration
MaximumrefrigerantconcentrationofR410Aofaroom
is 0.44kg/KaccordancewithISO5149-1.
Tofacilitatecalculation,themaximumconcentrationis
expressedinunitsofkg/K(kgofR410AperK)
(ISO5149-1)
MaximumconcentrationofR410A:0.44kg/K
10-3-2. Confirming procedure of R410A concentration
(b) There are partitions, but there are openings that allow
the effective mixing of air.
(c) 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.
Total refrigerant in the refrigerating unit (kg)
[Maximumconcentration(kg/
K )
Thesmallestroominwhichanindoor
unit has been installed ( K )
MaximumconcentrationofR410A:0.44kg/
K
(a) Situation in which there are no partitions
(3) Use the results of calculations (1) and (2) to calculate the refrigerant concentration:

Mitsubishi Electric CITY MULTI PUMY-SP140YKM Specifications

General

Brand	Mitsubishi Electric
Model	CITY MULTI PUMY-SP140YKM
Category	Air Conditioner
Language	English