
41
9.12 Chimney Sweep Function (CO
2
Adjust)
For correct boiler operation, content of (CO
2
- O
2
) in the combustion flue must be within tolerances indicated in table below.
COMBUSTION TABLE
Gas A
(Natural Gas)
DCBF-125
Gas A
(Natural Gas)
DCCF- 150
Gas E (LPG)
CO2 %
O2 %
CO2 %
O2 %
CO2 %
O2 %
Maximum
power (100%)
Nominal value
8.7
5.4
9.0
4.9
10.0
6.0
Permitted value 8.2 – 9.3 6.3 – 4.3
8.5 – 9.5 5.7 – 4.0 9.5 – 10.5 6.8 – 5.2
Ignition power
(*)
Nominal value
8.7
5.4
8.7
5.4
10.8
4.8
Permitted value 8.2 – 9.3 6.3 – 4.3
8.2 – 9.3 6.3 – 4.3 10.3 – 11.3 5.5 – 4.1
Minimum
power (0%)
Nominal value
8.8
5.2
8.8
5.2
10.0
6.0
Permitted value 8.2 – 9.3 6.3 – 4.3
8.2 – 9.3 6.3 – 4.3 9.5 – 10.5 6.8 – 5.2
Chimney Sweep Function enables boiler to generate maximum
heating power.
After activation, boiler power % can be adjusted from
minimum (0%) to maximum (100%) in DHW mode.
A. Press and hold
and
at the same time for 6
seconds. When the function is enabled, displays shows
“On
” for few seconds followed by program row “
303
”
alternating with % of boiler power.
B. Press
to gradually adjust power (increments of
1%).
C. To exit press both buttons together for at least 6
seconds.
If value of CO
2
-O
2
is different, check the electrodes and their
relative distances. See Figure 11-1.
If necessary, replace electrodes and position them correctly.
If problem persists, use "COMBUSTION ADJUSTMENT
FUNCTION (CO
2
%)". See Section 11 General Maintenance,
Figure 11-1 Electrodes. If problem persists, use Section 9.8
Automatic Calibration Function, and Section 9.9 Manual
Calibration Function.
NOTICE
• Press
to display instantaneous flow temperature
for 15 seconds.
• Use a regularly calibrated combustion analyzer for
combustion analysis.
• During normal operation boiler performs combustion
control cycles. In this phase CO values higher than
400 ppm can occur for brief periods of time.
(*)
Automatically calculated from the PCB
9.14 Check Firing Rate
1.
Measure input, if a gas meter is installed in the system.
•
Turn off gas to all other appliances.
• Activate some heating zones to dissipate heat.
•
Set boiler on high fire using Chimney Sweep Function.
• Use ½, 1 or 2 cu ft dial on gas meter. Measure time
required for two or more complete revolutions. Measure
time
for one or more minutes.
• Calculate input.
9.13 Combustion Adjustment Function (CO
2
%)
This function sets out to partially adjust the value of CO
2
%.
Use the following procedure:
1.
Press buttons
and
together for at least 6 seconds.
When the function is enabled, displays shows “On
” for a
few seconds followed by program row “304
” alternated
with the % of boiler power;
2.
After burner is lit, boiler reverts to maximum DHW power
(100). When display shows "100" it is possible to partially
adjust value of CO
2
%;
3.
Press
and
. Display shows "00" alternating with
function number "304" (
flashes);
4.
Press
to raise or lower the amount of CO
2
(from -0.3% to +0.3%);
5.
Press
to save new value. Power value "100" will show
on display again. Boiler continues operating at maximum
DHW power.
This procedure can be used to adjust CO
2
to ignition power
and minimum power by pressing
after performing step
5 above.
6.
After saving the new value (step 5 above), press
to set boiler to ignition power. Wait for value of CO
2
to stabilize. Adjust as described in step 4 of procedure
(power value is a number <> 100 and <> 0). Repeat step
5 to save.
7.
Press
to adjust boiler to minimum power. Wait for
value of CO
2
to stabilize. Go to step 4 to adjust (power
value = 00);
8.
Exit function by pressing
and
together for at least
6 seconds, see step 1.
9 - START UP PROCEDURE
240012564 REV A, [05/15/2019]