ISU-689:2016/GB
8
In the operating system type B, the boiler must be equipped only
with a flue gas adapter as shown on Fig. 3.8.1.1. The air is sucked
from
the room through the hole in the boiler’s top cover.
Fig. 3.8.1.1
–
Adjusting the boiler for operation in system B
23
3.8.2. Configuration Type B with closed chamber and forced
draft
The air is sucked from the outside through an individual air duct.
In case of using a separate flue gas-air system, the boiler should be
equipped with the appropriate adapters according to Fig. 3.8.2.1.
Fig. 3.8.2.1
–
Mounting the flue gas adapter and the separate air system
No
Name
Attached to the boiler
Quantity
1
Adapter
ø
100
Yes
2
2
Flat gasket
Yes
2
3
Sheet screw
Yes
8
3.8.3. Maximum length of the air-flue system
The maximum length of the flue pipe for a boiler that
co-operates with flue gas and air pipes with diameter of
Φ
100 is: L
MAX
= 30m.
The following table shows the values which have to be added to the
sum of the lengths of the flue gas-air system when the elbow is
mounted on the flue gas system or the air supply system to the
boiler.
Table 3.8.3.1 - Reduce the length of the installation elbows
Example of calculation of flue gas system length:
L
MAX
≥ H
1
+ H
2
+ K
90
x 1m+K
45
x 0.5m
L
MAX
- declared maximum length of the flue gas pipe
H
1
- sum of straight pipe lengths in the flue gas system
H
2
- sum of pipe lengths in the air system
K
90
-
quantity of used 90 ° elbows in the flue gas and air system
K
45
-
quantity of used 45 ° elbows in the flue gas and air system
3.8.4. Horizontal outlet of air- flue gas system through the
wall
Fig. 3.8.4.1
–
Horizontal outlet of air- flue gas system through the
wall
The horizontal air tube should be mounted at an angle of
~ 3 ° so that rain water tha
t gets into the pipes would not
flood the boiler and flowed outside the building.
3.8.5. Vertical outlet of air- flue gas system through the roof
Fig. 3.8.5.1
–
Horizontal outlet of air- flue as system through the wall or on
the roof
3.8.6. Connection to the existing flue gas duct
Fig. 3.8.6.1
–
Connection to the existing flue gas outlet duct
Elbow 15
°
Elbow 45
°
Elbow 90
°
0.25
0.5
1m
