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25
Adjustment info
fig. 27
fig. 26
16
12
17
13
18
14
19
15
20 21
25
22
26
23
27
24
28
BTFS 28
PROPAN
BUTAN
NAT. GAS
5
10
15
20
25
30
35
40
0
Power supply (kW)
B
u
rn
er
p
re
ss
u
re
(
m
ba
r)
CAP
CH - POWER
16
12
17
13
18
14
19
15
20 21
25
22
26
23
27
24
28
BTN 28
PROPAN
BUTAN
NAT. GAS
5
10
15
20
25
30
35
40
0
Power supply (kW)
B
u
rn
er
pr
ess
u
re
(m
bar
)
2.7 - ADAPTING THERMAL
POWER TO THE HEA-
TING SYSTEM
With the heating system cold.
Connect the pressure gauge to the burner
as shown in fig. 24, switch on the boiler in
heating mode and proceed as follows.
-
Wait about two minutes to allow the pres-
sure to reach the operating value.
-
Read the pressure measured and check
that the thermal power generated by the
boiler suits the installation requirements.
-
If necessary –
but this is not compul-
sory –
you can regulate the potentiome-
ter
CH POWER
on the modulation board
to adjust the thermal power to the heating
system. Turn the potentiometer
clockwise
(seen from the front) to increase the
pressure or
anticlockwise
to decrease
it.
Note
Since the boiler is the modulating type, it
automatically adapts the thermal power
to the features of the heating system. By
operating potentiometer
CH POWER
you
effectively limit the maximum power of the
boiler and hence its pickup capacity.
Using the pressure/thermal power graph
(fig. 26)
Assuming that the heating system has a
total absorption of 18 kW, using the graph
in figure you can determine the maximum
pressure at which the burner can be set.
Example 1
If the boiler runs on methane gas, adjust
the potentiometer
CH POWER
to set the
pressure to 7,3 mbar for version TN and
to 7,1 mbar for version TFS.
Example 2
If the boiler runs on butane gas, adjust
the potentiometer
CH POWER
to set the
pressure to 12,5 mbar for version TN and
to TFS.
Example 3
If the boiler runs on propane gas, adjust
the potentiometer
CH POWER
to set the
pressure to 15,3 mbar for version TN and
to 15,5 mbar for version TFS.
GAS PRESSURE BURNER DIAGRAM CORRESPONDING TO
THE SYSTEMS OUTPUT