Riello PRESS 2G - Flue Gas Temperature; Combustion Chamber Pressure; Loss of Heat from the Flue

20140894
34
GB
Start-up, calibration and operation of the burner
7.6 Flue gas temperature
This temperature varies in relation to the delivery generated: the
lower the delivery, the lower the temperature and the higher the
fuel saving.
Bear in mind that excessive temperature reduction, however,
gives rise to the formation of condensate.
7.7 Combustion chamber pressure
This must correspond to the setting indicated by the boiler man-
ufacturer.
Chamber pressure is lowered with reduced burner delivery and
higher CO
2
levels.
If the combustion chamber pressure is significantly higher than
expected and the burner's delivery is correct, make sure that the
boiler is not dirty, that the flue gas duct is not obstructed, and that
the flue gas stack has been correctly sized.
7.8 Loss of heat from the flue
Heat losses from the flue gas stack Qs are determined by the for-
mula given on page 41 or Diagram (Fig. 35).
T2 - T1 = Flue gas temperature - Ambient temperature
130 150 200
250
300
10
11
12
13
14
15
16
17
10
11
12
13
14
Qs
CO
T2 - T1
T2 - T1 = 200 CC = 13%
Qs = 9%
Fig. 35
D347