Ka
ysun Amaz
on Unit
ario T
op Dischar
ge Engineering Da
ta Book
Amazon Unitario Top Discharge
150
4.5 Refrigerant Piping Selection Example
The example below illustrates the piping selection procedure for a system consisting of one outdoor unit (16HP) and 10 indoor
units. The system’s equivalent length of all liquid pipes is in excess of 90m; the piping between the farthest indoor unit and
the first indoor branch joint is less than 40m in length; and each indoor auxiliary pipe (from each indoor unit to its nearest
branch joint) is less than 10m in length.
Figure 3-4.4: Refrigerant piping selection example
Step 1: Select indoor auxiliary pipes
Indoor units N
1
to N
5
, and N
8
are of capacity 5.6kW and their indoor auxiliary pipes are less than 10m in length. Refer
to Table 3-4.6. Indoor auxiliary pipes a to e, and h are Φ15.9 / Φ9.53.
Indoor units N
6
, N
7
, N
9
and N
10
are of capacity less than 4.5kW and their indoor auxiliary pipes are less than 10m in
length. Refer to Table 3-4.6. Indoor auxiliary pipes f, KAYF, i and j are Φ12.7 / Φ6.35.
Step 2: Select indoor main pipes and indoor branch joints B to I
The indoor units (N
1
and N
2
) downstream of indoor branch joint C have total capacity of 5.6 + 5.6 = 11.2kW. Refer to
Table 3-4.4. Indoor main pipe L
3
is Φ15.9 / Φ9.53. Indoor branch joint C is KCMI112.
The indoor units (N
1
to N
4
) downstream of indoor branch joint B have total capacity of 5.6 x 4 = 22.4kW. Refer to Table
3-4.4. Indoor main pipe L
2
is
Φ19.1 / Φ9.53. Indoor branch joint B is KCMI112.
The other indoor main pipes and indoor branch joints are selected in the same fashion.
Step 3: Select main pipe and indoor branch joint A
The indoor units (N
1
to N
10
) downstream of indoor branch joint A have total capacity of 5.6 x 6 + 2.8 x 4 = 44.8kW. The
system’s equivalent length of all liquid pipes is in excess of 90m. The capacity of the outdoor unit is 16HP. Refer to
Tables 3-4.4 and 3-4.5. Main pipe L
1
is the larger of
Φ28.6 / Φ12.7 and Φ34.9 / Φ15.9, hence Φ34.9 / Φ15.9. Indoor
branch joint A is KCMI412.
Legend
L
1
Main pipe
L
2
to L
9
Indoor main pipes
a to j
Indoor auxiliary pipes
A to I
Indoor branch joints
Figures in parentheses indicate indoor unit
capacity indexes.
