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Check of Density Limit

The room in which the air conditioner is to be installed requires a design that in the event of refrig- erant gas leaking out, its density will not exceed a set limit.

The refrigerant (R410A), which is used in the air condition- er, is safe, without the toxicity or combustibility of ammonia, and is not restricted by laws imposed to protect the ozone layer. However, since it contains more than air, it poses the risk of suffocation if its density should rise excessively. Suf- focation from leakage of refrigerant is almost non-existent. With the recent increase in the number of high density buildings, however, the installation of multi air conditioner systems is on the increase because of the need for effec- tive use of floor space, individual control, energy conserva- tion by curtailing heat and carrying power, etc.

Most importantly, the multi air conditioner system is able to replenish a large amount of refrigerant compared to conventional individual air conditioners. If a single unit of the multi air conditioner system is to be installed in a small room, select a suitable model and installation pro- cedure so that if the refrigerant accidentally leaks out, its density 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 density may exceed the limit, create an opening with adjacent rooms, or install mechanical ventilation combined with a gas leak detection device. The density is as given below.

Total amount of refrigerant (lbs)

Min. volume of the indoor unit installed room (ft.3)

<Density limit (oz/ft.3)

The density limit of refrigerant which is used in multi air condi- tioners is 0.3 oz/ft.3 (ISO 5149).

NOTE

1.If there are 2 or more refrigerating systems in a single refrigerating device, the amount of refrigerant should be as charged in each independent device.

For the amount of charge in this example:

Outdoor unit

e.g., charged

e.g., charged

2.The standards for minimum room volume are as fol- lows.

(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).

Outdoor unit

Refrigerant tubing

Indoor unit

(3)If an indoor unit is installed in each partitioned room and the refrigerant tubing is interconnected, the small- est room of course becomes the object. But when 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 small- est room becomes the object.

 

 

Refrigerant tubing

 

 

Outdoor unit

Very

 

 

small

 

Indoor unit

room

 

 

 

Small

Medium

Large room

room

room

 

Mechanical ventilation device – Gas leak detector

3.The minimum indoor floor space compared with the amount of refrigerant is roughly as follows: (When the ceiling is 8.8 ft. high)

ft.3

ft.2

4000

 

 

 

 

454

 

 

 

 

 

 

 

 

 

 

amount (353 oz)

amount (529 oz)

Indoor unit

Room A Room B Room C Room D Room E Room F

The possible amount of leaked refrigerant gas in rooms A, B and C is 353 oz.

The possible amount of leaked refrigerant gas in rooms D, E and F is 529 oz.

Min. indoor volume

3500

 

Range below

 

 

 

 

 

 

 

 

 

3000

 

the density limit of

 

 

 

0.3 oz/ft.3

 

 

 

 

 

 

 

 

 

2500

 

(countermeasures

 

 

 

not needed)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2000

 

 

 

 

 

 

 

 

 

1500

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Range above

 

 

 

 

 

 

1000

 

 

 

 

 

the density limit of

 

 

 

 

 

500

 

 

 

 

 

0.3 oz/ft.3

 

 

 

 

 

 

(countermeasures

 

 

 

 

 

0

 

 

 

 

 

needed)

 

 

 

 

 

 

 

 

 

 

0

200

400

600

800

1000

 

 

Total amount of refrigerant

398

 

h)

 

 

area

g

341

ft.8. hi

 

 

284

doorn floor

ceiling is 8

170

227

 

 

 

114

Min. i

n the

 

 

57

 

(whe

 

 

0

 

 

1200

 

 

 

oz

 

 

3

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Sanyo 85464359982001 installation instructions Check of Density Limit