43
Tec
hnical f
eatures and dimensions
3.13.4 - COMBUSTION POWER
MODULATION
The circuit board simultaneously performs two combustion
output modulations:
1 Modulation of flue gas temperature
2 Modulation of boiler temperature
The modulation of the flue gas temperature limits the
temperature of the gas coming out of the flue.
The limitation is defined by parameter no. 15 (Maximum
Flue Gas Temperature) which is the maximum limit allowed
for outlet flue gas.
The board acts on the fan speed by decreasing the speed
15°C before parameter no. 15 in three 5°C steps.
For example, if the maximum allowed temperature is
180°C, when the flue gas temperature rises, the fan is
slowed down at a set rate of 5 points for each step.
If the flue gas temperature reaches the maximum, the fan
is stopped by 50 points.
Modulation of the boiler temperature is performed on an
8°C scale in four 2°C steps, starting from the boiler working
temperature defined by parameter no. 0 (see the list of
parameters electro-plumbing diagram page 23).
Furthermore, it is possible to set higher or lower modula-
tion according to parameter no. 14 (Modulation Step) to
adjust the fan stopping points as the temperature rises.
Massima Temp. Fumi 180°C
Velocità nominale
-5 Punti
-10 Punti
-15 Punti
-50 Punti
-5°C
-10°C
-15°C
Temp. Lavoro Caldaia 80°C
Velocità nominale
-2 Punti
-4 Punti
-6 Punti
-8 Punti
76°C
78°C
74°C
72°C
Boiler operating Temp. 80°C
For example, if parameter no. 0 (Boiler working temper-
ature) is set at 80°C and parameter no. 13 (Modulation
Step) is set at 2 points, the fan speed will be decreased
by a total of 8 points.
The two modulations can overlap if both are required gen-
erating the sum of the stopping points of both modulations.
Maximum Flue Gas Temp. 180°C
Nominal speed
Points
Points
Points
Points
Points
Points
Points
Points
Nominal speed
Summary of Contents for NOVAIREX Series
Page 1: ...INSTALLATION AND MAINTENANCE INSTRUCTIONS NOVAIREX 35 45 55 ...
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