3
D
ispLAy
p
ArAmEtErs
O
n
UE
i
C
OmbUstiOn
A
nALyzErs
•
TF
=
Flue Temperature
: Calculate net temperature in °F or °C.
- Shows ambient temp after fresh air calibration and ‘
- O C -
’ when probe is disconnected.
•
T
=
Net Temperature
:
- Differential of flue temperature minus ambient (or inlet) temperature
- Differential of T1 - T2
•
T∆
=
Temperature Differential
:
•
O2
=
Oxygen
: O2 percentage displayed
•
CO
=
Carbon Monoxide
: CO ppm (parts per million) displayed.
- ‘
- - - -
’ or ‘
- OC -
’ is displayed if there is a fault with the CO sensor or
the instrument has not been zeroed correctly, switch off instrument and try again.
•
CO2
=
Carbon Dioxide:
- EAGLE (C125 & C127) Calculated from the fuel selected and the measured O2 level
- EAGLE (C125 & C127) Will display ‘
- - - -
’ or ‘
-O>-
’ if the O2 level is too
high to calculate CO2 or in fresh air.
- Calculated value is only displayed during the combustion test.
- EAGLE X (C155 & C157) Direct measurement CO2 ppm (parts per million) displayed.
•
X
=
Excess Air:
- Indicated as ‘
XAIR %
’ on the printout
- A calculated percentage of O2 above the theoretical level required for complete combustion.
-
Is required to completely burn the fuel due to poor mixing and assisting in venting flue gases
-
Only displays a reading during combustion test.
- ‘
- - - -
’ or ‘
-O>-
’ is displayed in fresh air.
•
EFF
=
Efficiency
:
- Calculated based on gas readings, net temperature and fuel selected.
- Value is combustion efficiency, not appliance efficiency.
•
∆
=
Loss
:
- Total losses calculated from Combustion Theory. A summation of the next three parameters
• Dry %: Calculated heat lost turning the Carbon in the fuel to Carbon Dioxide (CO2)
• Wet %: Calculated heat lost turning the Hydrogen in the fuel into water (H2O)
• CO Loss %: Calculated loss due to partially burnt Carbon.
Any CO in the flue has the potential to be turned into CO2 releasing and losing more
heat up the flue.
•
CO a
=
Carbon Monoxide Air-Free
: Referenced to an oxygen level of 0%.
-
Do not confuse this reading with the actual CO reading
as detailed above.
- See the Combustion Efficiency Calculation sections for more details.
•
AMB
=
Air Inlet
:
- Temperature used to calculate the NET temperature.
•
CO/CO2
=
CO/CO2 Ratio
: The ratio of measured CO divided by CO2.
- It gives an indication of:
• How good a gas sample the instrument is reading.
• How clean the boiler is running.
- Example: A new or clean domestic boiler will display a ratio of less than 0.004, a unit in need
of cleaning 0.004 - 0.008 and a unit needing a major overhaul will show at least 0.008.
- Only displays a reading during combustion test. ‘
- - - -
’ is displayed while in fresh air.
•
D
=
Draft Pressure
•
P
=
Pressure
•
NO
=
Nitric Oxide
:
•
-PO-
=
Pump Off
:
- Measured gases will display this when pump is off.
•
-O>-
=
High O2 level
:
- Calculated values will display this when O2 levels are greater than 18%
- Values are calculated with fuel choice and the O2 readings
•
-OC-
=
Probe Not Connected
:
- Temperature values will display this when the probe is not connected or is open
- Press and hold the “PUMP” button to Zero the pressure sensor in selector positions that display
measured or calculated values “Aux” & “Flue Test”.
•
N/F
=
Not Found
:
- Displayed when not available or not installed ie: NO on a C155 or C125.
NOTE: See page 8 for complete auxiliary display listings.
