Otec BSCF-D ULTIMA Series User manual

1
CONTENTS
Part 1 General Information............................................................................ 3
Part 2 Outdoor Unit Engineering Data ....................................................... 13
Part 3 System Design and Installation........................................................ 69

3
Part 1
General Information
1 Indoor and Outdoor Unit Capacities........................................................ 4
2 External Appearance............................................................................... 5
3 Nomenclature......................................................................................... 6
4 Combination Ratio .................................................................................. 7
5 Selection Procedure ................................................................................ 8

4
1Indoor and Outdoor Unit Capacities
1.1 Indoor Units
Table 1-1.1: Indoor unit abbreviation codes
Abbreviation code
Type
BECW
One-way Cassette
BECM
Compact Four-way Cassette
BECS
Four-way Cassette
BEMP
Medium Static Pressure Duct
BEWM
Wall-mounted
Table 1-1.2: Indoor unit capacity range
Capacity
Capacity
index
BECW BECM BECS BEMPBEWM
kBtu/h
kW
HP
6
1.8
0.6
6
6
—
—
—
—
7
2.2
0.8
7
7
7
—
7
7
9
2.8
1
9
9
9
9
9
9
12
3.6
1.25
12
12
12
12
12
12
15
4.5
1.6
15
15
15
15
15
15
18
5.6
2
18
18
—
18
18
18
24
7.1
2.5
24
24
—
24
24
24
28
8.0
3
28
—
—
28
28
28
32
9.0
3.2
32
—
—
32
32
32
36
10.0
3.6
36
—
—
36
—
—
40
11.2
4
40
—
—
40
40
—
48
14.0
5
48
—
—
48
48
—
56
16.0
6
56
—
—
—
56
—
Notes:
1. ULTIMA series indoor units could connect to ULTIMA series outdoor units.
1.2 Outdoor Units
Table 1-1.3: Outdoor unit capacity range
Nominal Cooling Capacity (kBtu/h)
Model Name
30.7 BCSF030N0A4-DTM090
37.5 BCSF040N0A6-DTM115
47.8 BCSF050N0A7-DTM140
54.6 BCSF060N0A8-DTM160
64.8 BCSF070N0A9-DTM190
Notes:
1. ULTIMA series outdoor units could not be combined.

5
2External Appearance
2.1 Indoor Units
Table 1-2.1: Indoor unit appearance
2.2 Outdoor Units
Table 1-2.2: Outdoor unit appearance
30/40/50 Models 60/70 Models
One-way
Cassette
Four-way Cassette
Compact Four-way Cassette Wall-mounted
Medium Static Pressure Duct

7
4Combination Ratio
Table 1-4.1: Indoor and outdoor unit combination ratio limitations
Type
Minimum combination ratio
Maximum combination ratio
ULTIMA Series outdoor units
45%
130%
Table 1-4.2: Combinations of Indoor and outdoor units
Outdoor unit capacity
Sum of capacity indexes of
connected indoor units (standard
indoor units only)
Number of connected
indoor units
kBtu/h
Capacity
index
30.7
28
12.6 to 36.4
1-4
37.5
36
16.2 to 46.8
1-6
47.8
42
18.9 to 54.6
1-7
54.6
48
21.6 to 62.4
1-8
64.8
56
25.2 to 72.8
1-9
Combination ratio =
Sum of capacity indexes of the indoor units
Capacity index of the outdoor unit

8
5Selection Procedure
5.1 Procedure
Step 1: Establish design conditions
Step 2: Select indoor units
Step 3: Select outdoor unit
Notes:
1. If the indoor design temperature falls between two temperatures listed in the indoor unit's capacity table, calculate the corrected capacity by interpolation.
If the indoor unit selection is to be based on total heat load and sensible heat load, select indoor units which satisfy not only the total heat load requirements
of each room but also the sensible heat load requirements of each room. As with total heat capacity, the sensible heat capacity of indoor units should be
corrected for indoor temperature, interpolating where necessary. For the indoor unit capacity tables, refer to the indoor unit technical manuals.
Yes
Design temperature and humidity (indoor and outdoor)
Required heat load of each room
System peak load
Piping length, level differences
Indoor unit specifications (type and quantity)
Decide indoor unit safety factor
Select indoor unit models ensuring that:
Indoor unit capacity corrected for indoor air temperature WB1 ≥ Required heat load × Indoor unit safety factor
Determine required total heat load on the outdoor unit
Use the sum of the peak load of each room
Use the system peak load
Provisionally select outdoor unit capacity based on combination ratio limitations
Confirm that the number of indoor units connected to the outdoor unit is within limitation
Correct cooling and heating capacities of the outdoor unit for the following items:
Outdoor air temperature / Indoor air temperature WB / Combination ratio / Piping length, level difference
/ Piping heat loss / Frost accumulation (for heating capacity only)
Is corrected outdoor unit capacity ≥ Required total heat load on outdoor unit?
VRF system selection is complete
No

9
5.2 Example
The following is a selection example based on total heat load for cooling.
Figure 1-5.1: Room plan
Room A
Room B
Room C
Room D
Step 1: Establish design conditions
Indoor air temperature 25°C DB, 18°C WB; outdoor air temperature 33°C DB.
Determine peak load of each room and system peak load. As shown in Table 1-5.1, the system peak load is 10.5kW.
Table 1-5.1: Required heat load of each room (kW)
Time
Room A
Room B
Room C
Room D
Total
9:00
2.5
1.6
1.6
1.6
7.3
12:00
3.2
2.4
2.4
2.4
10.4
14:00
3.1
2.4
2.4
2.6
10.5
16:00
3.1
2.3
2.3
2.3
10
The maximum piping lengths and level differences in this example are as given in Figure 1-5.2.
Figure 1-5.2: System diagram
Indoor unit type for all rooms: Medium Static Pressure Duct (T2).
Step 2: Select indoor units
In this example, a safety factor is not used (i.e. the safety factor is 1).
Select indoor unit models using the medium static pressure duct cooling capacity table. Each indoor unit's corrected
capacity needs to be greater than or equal to the peak load of the relevant room. The selected indoor units are shown
in Table 1-5.3.
Equivalent length of piping 50m
Level
difference
20m
Outdoor
Unit
Indoor
Unit
Indoor
Unit
Indoor
Unit
Indoor
Unit

10
Table 1-5.2: Extract from medium static pressure duct (T2) cooling capacity table
Model
Capacity
index
Indoor air temperature
14°C WB
16°C WB
18°C WB
19°C WB
20°C WB
22°C WB
24°C WB
20°C DB
23°C DB
26°C DB
27°C DB
28°C DB
30°C DB
32°C DB
kBtu/h
kW×10
TC
SHC
TC
SHC
TC
SHC
TC
SHC
TC
SHC
TC
SHC
TC
SHC
T2
7
22
1.5
1.4
1.8
1.5
2.1
1.6
2.2
1.6
2.3
1.7
2.4
1.5
2.4
1.5
9
28
1.9
1.7
2.3
1.9
2.6
2.1
2.8
2.1
3.0
2.1
3.1
2.0
3.1
1.9
12
36
2.5
2.1
2.9
2.3
3.4
2.5
3.6
2.6
3.8
2.7
4.2
2.8
3.9
2.3
15
45
3.1
2.6
3.7
2.8
4.2
3.1
4.5
3.2
4.8
3.2
4.9
3.1
5.1
2.9
18
56
3.9
3.0
4.6
3.3
5.3
3.6
5.6
3.7
5.9
3.8
6.2
3.7
6.2
3.4
24
71
4.9
3.9
5.8
4.3
6.7
4.7
7.1
4.9
7.5
4.8
7.8
4.6
7.8
4.3
28
80
5.5
4.4
6.6
4.9
7.5
5.3
8.0
5.5
8.4
5.5
8.8
5.2
8.8
4.8
32
90
6.2
5.3
7.3
5.8
8.4
6.3
9.0
6.4
9.6
6.5
9.9
6.1
9.9
5.7
40
112
7.7
6.4
9.1
7.1
10.5
7.7
11.2
7.8
11.9
8.1
12.5
7.8
12.5
7.4
48
140
9.7
7.8
11.3
8.6
13.2
9.6
14.0
9.8
14.8
9.8
15.7
9.7
15.4
8.8
Abbreviations:
TC: Total capacity (kW); SHC: Sensible heat capacity (kW)
Table 1-5.3: Selected indoor units
Room A
Room B
Room C
Room D
Peak heat load (kW)
3.1
2.4
2.4
2.6
Selected indoor unit
3.6 kW Indoor 2.8 kW Indoor 2.8 kW Indoor 2.8 kW Indoor
Corrected TC (kW)
3.6
2.8
2.8
2.8
Step 3: Select outdoor unit
Determine the required total heat load from the indoor units to the outdoor unit based on either the sum of the peak
loads of each room or the system peak load. In this example, it is determined based on the system peak load. Therefore,
the required heat load is 10.5kW.
Provisionally select an outdoor unit using the sum of the capacity indexes (CIs) of the selected indoor units (as shown
in Table 1-5.4), ensuring that the combination ratio is between 50% and 130%. Refer to Table 1-5.5. As the sum of CIs
of the indoor units is 120, all outdoor units are potentially suitable except 8kW. Start from the smaller, which is the
10kW unit.
Table 1-5.4: Sum of indoor unit capacity indexes
Model
Capacity Index
No. of units
3.6 kW Indoor
36
1
2.8 kW Indoor
28
3
Sum of CIs
120
Table 1-5.5: Combinations of Indoor and outdoor units
Outdoor unit capacity
Sum of capacity indexes of
connected indoor units
(standard indoor units only)
kBtu/h
Capacity
index
30.7
28
14 to 36.4
37.5
36
18 to 46.8
47.8
42
21 to 54.6
54.6
48
24 to 62.4
64.8
56
28 to 72.8

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The number of connected indoor units is 4 and the maximum number of connected indoor units on the 10kW outdoor
unit is 6, so the number of connected indoor units is within the limitation.
Calculate the corrected capacity of the outdoor unit:
a) The sum of the indoor unit CIs is 120 and the CI of the 10kW outdoor unit is 100, so the combination ratio is 120 /
100 = 120%.
b) Using the outdoor unit’s cooling capacity table, interpolate to obtain the capacity (“B”) corrected for outdoor air
temperature, indoor air temperature, and combination ratio. Refer to Tables 1-5.6 and 1-5.7.
Table 1-5.6: Extract from Table 2-7.2 BCSF040N0A6-DTM115
cooling capacity
Table 1-5.7: Cooling capacity calculated by interpolation
CR
Outdoor
air
temp.
(°C DB)
Indoor air temp.
(°C DB / °C WB)
CR
Outdoor
air
temp.
(°C DB)
Indoor air temp.
(°C DB / °C WB)
25.8 / 18.0
25.8 / 18.0
TC
PI
TC
PI
kW
kW
kW
kW
120%
31
10.60
2.02
120%
33
10.42
2.10
33
10.42
2.10
35
10.26
2.18
B =10.44
110%
31
9.86
2.07
110%
33
9.86
2.16
33
9.86
2.16
35
9.86
2.21
c) Find the correction factor for piping length and level difference (“K1”)
Figure 1-5.3: ULTIMA rate of change in cooling capacity
30
10
1.0
0.98
0.97
0.95
0.96
0.96
0.97
0.98
1.0
20
10
0
0
-10
-20
20 30 40 50
d) Calculate the corrected capacity of BCSF040N0A6-DTM115 (“C”) by using K1:
C = B × K1 = 10.42 × 0.95 =9.9kW
The corrected capacity 9.9 kW is lower than required total heat load 10.5kW, so selection is not complete. Step 3 should
be repeated from the point where the outdoor unit capacity is provisionally selected.
Repeat Step 3: Select outdoor unit
Determine the required total heat load from the indoor units to the outdoor unit based on either the sum of the peak
loads of each room or the system peak load. In this example, it is determined based on the system peak load. Therefore,