Bosch Therm 8000 S Installation And Operating Instructions Manual page 34

34 | Installation instructions
Before adjusting the fan speed it is necessary to verify the
admission / exhaustion system, calculating the total length of
the exhaust pipes and quantity of elbows.
Pressure drop equivalence of the conducts and exhaustion
accessories
Description
30° elbow
45° elbow
90° elbow
exhaust pipe per meter
Horizontal vent kit
Table 16
8.6.1 Total equivalent vent length calculation Ø80 mm
How to calculate the total length of the exhaust conduct:
▶ Determine the total length of all straight sections of vent
pipe and enter in Table 17 , line 1.
▶ Count the number of 90° elbows used, multiply by 1m, and
enter that value in Table 17 , line 2. (Do not count non-
concentric terminals and first elbow used on intake and
exhaust ).
▶ Count the number of 45° elbows used, multiply by 0.5m,
and enter that value in Table 17 , line 3.
▶ Count the number of 30° elbows used, multiply by 0.4m,
and enter that value in Table 17 , line 4.
Do not count non-concentric terminals and
first elbow used on intake and exhaust.
▶ Repeat the previous procedure to calculate the total length
of the admission of air conduct. Insert values in Table 18 .
▶ Sum the total of the Table 17 with the total of the Table 18
and to put the result in the line 6 of the Table 18 .
This is the total equivalent vent length.
6 720 680 174 (2014/05)
Equivalence in meters
Ø80/80mm Ø80/125mm
0.4m 0.7m
0.5m 1.5m
1m 2m
1m 1m
- 1.5m
Exhaust
1 Straight section length ___ x 1 =
2 90° elbows (qty)
3 45° elbows (qty)
4 30° elbows (qty)
5 Sub-total:
Table 17
Intake
1 Straight section length
2 90° elbows (qty)
3 45° elbows (qty)
4 30° elbows (qty)
5 Sub-total:
6 Total equivalent vent length=
Table 18
Example
Exhaust:
• 5 units of 1m straight sections
• 1 unit of 1m straight sections
– Total length = 6 meters
• 2 - 90° elbows
Intake:
• 4 units of 1m straight sections
– Total length = 5 meters
• 2 - 90° elbows
Example table:
Exhaust
1 Straight section length
2 90° elbows (qty)
3 45° elbows (qty)
4 30° elbows (qty)
5 Sub-total:
Table 19
________
___x 1 = ________
___x 0.5 = ________
___x 0.4 = ________
________
___ x 1 = ________
___x 1 = ________
___x 0.5 = ________
___x 0.4 = ________
________
________
6 x 1 = 6
_1_ x 1 = 1
_0_ x 0.5 = 0
_0_ x 0.4 = 0
7
Therm 8000S