31
MULTI V S Outdoor Unit
Special Guide
1. Caution For Refrigerant Leaks
The installer and system specialist shall secure safety against leakage according to local regulations or standards.
The following standards may be applicable if local regulations are not available.
1.1 Introduction
The R410A refrigerant itself is harmless and nonflammable, but even if the refrigerant gas leaks into the room, the
space for installing the air conditioner should be large enough that the refrigerant gas does not exceed the limit
concentration.
1.1.1 Limiting concentration
1.2 Checking procedure of limiting concentration
Check limiting concentration along following steps and take appropriate measure depending on the situation.
1.2.1 Calculate amount of all the replenished refrigerant (kg) per each
refrigerant system.
Calculate amount of all the replenished refrigerant (kg) per each refrigerant system.
In case one refrigerant facility is divided into 2 or more refrigerant systems and each system is independent,
amount of replenished refrigerant of each system shall be adopted.
1.2.2 Calculate minimum room volume
Calculate room volume by regarding a portion as one room or the smaller room.
1. Without partition
Limiting concentration is the limit of Freon gas concentration where immediate measures can be taken without
hurting human body when refrigerant leaks in the air. The limiting concentration shall be described in the unit of
kg/m3 (Freon gas weight per unit air volume) for facilitating calculation.
Limiting concentration: 0.44kg/m
3
(R410A)
Amount of replenished refrigerant
per one outside unit system
+
Amount of additional replenished
refrigerant
=
Total amount of replenished
refrigerant in refrigerant facility
(kg)
Amount of replenished refrigerant
at factory shipment
Amount of additionally replenished
refrigerant depending on piping
length or piping diameter at
customer
Outdoor Unit
(No.1 system)
Flow of
refrigerant
Indoor unit
Room where refrigerant leaks
(Refrigerant of the whole No.1
system flows out.)
Indoor unit
Outdoor Unit