65
Optional measures list:
MEASURE
DEFINITION
λ,
n (l,n)
Air index
(defined as
λ,
sometimes also indicated as
n
).
e (Exc. Air)
Air excess.
Expressed as a percentage according to the formula in the appendix D, is
the ratio between the volume of air actually entering the combustion chamber and the one
theoretically needed.
Δ
T (dT)
Temperature Differential :
Is the difference between the smoke temperature and the air combustion temperature.
Qs (LHV)
Stack losses in relation to the Lower Heating Value:
Is the percentage of dissipated heat through the stack referred to the lower heating value
(LHV)
η
s (Es) (LHV)
Sensible efficiency in relation to the Lower Heating Value:
Is the burner efficiency calculated as the ratio between conventional heating power and
the burner heating power. Among the combustion losses, only the sensible heat lost with
flue gasses is taken into account, thus neglecting the radiation losses and incomplete
combustion losses. This value is referred to the Lower Heating Value (LHV) of the fuel
and cannot exceed 100%.
The sensible efficiency value is to be compared against minimum efficiency stated for the
heating system performances.
η
c (Ec) (LHV)
Condensation efficiency in relation to the Lower Heating Value:
Efficiency deriving from the condensation of water vapor contained in flue gases it is
referred to the LHV.
η
t (Eff) (LHV)
η
t =
η
s +
η
c
Total efficiency in relation to the Lower Heating Value:
Total efficiency. It is the sum of sensible efficiency and condensation efficiency. It is
referred to LHV (Lower Heating Value) and can exceed 100%.
NOx
Measure of nitrogen oxides quantity; the measurement unit can be set in the special
menu.
NOx ppm
Measure of nitrogen oxides quantity; the measurement unit can not be set but it is fixed in
ppm.
NOx (rif. O2)
Measure of nitrogen oxides quantity referring to O
2
; the measurement unit can be set in
the special menu.
NOx (rif. O2) ppm
Measure of nitrogen oxides quantity referring to O
2
; the measurement unit can not be set
but it is fixed in ppm.
PI
Poison Index (CO/CO
2
ratio)
:
It is defined as the ratio between CO and CO
2
useful to determine whether the system
needs maintenance.
CO
CO quantity measurement. Measurement units: ppm
-
mg/m
3
-
mg/kWh
-
ng/J
-
g/GJ
-
g/m
3
-
mg/kWh
-
%
CO (RIF)
CO quantity measurement with O2 reference. Measurement units: ppm
-
mg/m
3
-
mg/kWh
-
ng/J
-
g/GJ
-
g/m
3
-
mg/kWh
-
%
ANNEX B
