Robur Next-R, Инструкция по установке, использованию и техническому обслуживанию

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Heating engineer
28
3
Figure 3.7
Slope of horizontal pipes
For proper installation of the wall external terminals for the fl ue
gas exhaust and combustion air intake, follow the details given
in Figure 3.8
p. 28.
Figure 3.8
Wall terminal position
IN combustion air intake
OUT fl ue gas exhaust
A recommended position
(OK)
B allowed position (OK)
C position NOT allowed (NO)
IN OUT
A
IN
OUT
B
IN
OUT
C
NO OK
3.3.5
Example of calculation
Let's assume to install a R60 in C13 type installation (Figure
3.3 p. 25). The air/fumes system will be realized with Ø 80 sep-
arate pipes in the following way:
▶
7 m of Ø 80 fl ue gas exhaust pipe
▶
1 90° Ø 80 elbow on the fl ue gas exhaust pipe
▶
6 m of Ø 80 air pipe
It is therefore possible to proceed with the veri fi cation, remem-
bering that the maximum allowed pressure drop is 100 Pa (see
Table 3.11
p. 26).
▶
Ø 80 fl ue gas exhaust pipe
7 m x 9,2 Pa/m = 64,4 Pa
▶
90° elbow
1 x 15,4 Pa = 15,4 Pa
▶
Ø 80 air pipe
6 m x 4,4 Pa/m = 26,4 Pa
Total pressure drop = 106,2 Pa
Total pressure drop of the piping system is greater than the max-
imum allowed pressure drop (100 Pa), therefore the installation
is not allowed.
The installation can be done if one of the following steps is taken:
▶
Reduce the length of the air/fumes pipes.
▶
Increase pipe diameter, e.g. by using Ø 110. In this case the
total pressure drop would be:
7 m x 1,9 Pa/m = 13,3 Pa
1 x 4,3 Pa = 4,3 Pa
6 m x 0,9 Pa/m = 5,4 Pa
Total pressure drop = 23,0 Pa
which is therefore compatible with the maximum allowed pres-
sure drop.
3.3.6
Vertical down fl ow gas unit heaters
For vertical down fl ow gas unit heaters, at the base of
the vertically mounted fl ue gas exhaust pipe a T-shaped
piece must be fi tted to collect the condensate, to pre-
vent any condensate drops from reaching the blower
(Figure 3.9 p. 28).
Pay attention to the collection and the proper conveying
of the condensate drain.
Figure 3.9
Example of a vertical down fl ow gas unit heater installation
3.4
AIR DUCTING
Only models equipped with a centrifugal fan (Next-R C series)
can be combined with air ducting systems, which can be posi-
tioned both on the air intake (with or without mixing chambers)
and on the delivery.
For this purpose, the delivery outlet of the Next-R C gas unit heat-
ers is provided with fi xing fl anges for the delivery air ducting.
Refer to the Paragraph 1.2.2 p. 11 for the dimensions of the
fl ange connection.
In order to avoid vibrations (possible source of noise and
mechanical failures), it is advisable to install anti-vibra-
tion connections, easily removable for maintenance op-
eration, at the connection between the gas unit heater
and the air duct.
Set up the air ducting using a traditional su ffi ciently smooth