Checking Concentration Limit - Fujitsu Airstage J-II Series Design & Technical Manual

1-2. CHECKING CONCENTRATION LIMIT

Check concentration limit following steps  , and take appropriate measures depending on
the situation.
 Calculate amount of refrigerant [lbs. (kg)] per refrigerant system.
Amount of refrigerant per
refrigerant system
Amount of factory
charged refrigerant
 Smallest room volume.
Calculate room volume by regarding
(a) Without partition
(c) With partition and without
opening which serve as
passage of air to adjoining
room.
Indoor unit
Smallest
room
 Calculate refrigerant concentration from the results of  and 
Total amount of refrigerant in
refrigerant system (lbs,kg)
Capacity of smallest
room where indoor unit is
3
installed [cf (m
Amount of additional
+
refrigerant
Amount of refrigerant
added to system based
on pipe length, pipe size
and indoor units.
Outdoor unit
Indoor unit
Outdoor unit
≤ Refrigerant concentration [lbs./Mcf
(R410A)
)]
=
portion as one room or the smallest room.
(b) When there are partitions,
but there is an effective
opening for ventilation between
the rooms.
Opening
Indoor unit
Partition
When the result of calculation
exceeds the limiting
concentration,perform the same
(kg/m 3 )]
calculations by shifting to the
second smallest,and the third
smallest rooms until the final result
is below the limiting concentration.
- (09-02) -
Total amount of refrigerant in
system (lbs, kg)
Note : When one refrigerant
system is divided into 2 or more
refrigerant systems and each
system is independent, total
amount of refrigerant of each
system shall be adopted.
Outdoor unit