TECHNICAL ASSISTANCE SERVICE
48
Checking combustion parameters
Proceed as follows to perform combustion analysis:
- Unscrew the four screws (A) and remove the front trim
(B).
- Remove the screw (C) and the combustion analysis cap
(40) and insert the combustion analysis probe into the
air box.
- Check that the values for CO
2
correspond to the values
specified in the table. If the value displayed differs from
that specified, adjust the boiler as instructed in the
“Adjusting the gas valve” section.
- Repeat combustion analysis.
Then:
- Remove the combustion analysis probes and fit the cap
back over the hole with the screw.
- Fit the front trim (B) and secure with the four screws (A).
b
When inserting the combustion analysis probe, take
care to push it all the way in.
IMPORTANT
The safety function that shuts down the boiler if central
heating water reaches 85°C remains active even during
combustion analysis.
Autodiagnosis of primary heat
exchanger cleaning
The boiler incorporates an autodiagnosis system that
uses the number of hours of operation under certain con-
ditions to notify the user that the primary heat exchanger
needs cleaning (error code 91).
Clean the heat exchanger using the relevant accessory
kit, then proceed as follows to reset the hour counter:
- Switch off electrical power.
- Unscrew the four screws (A) and remove the front trim
(B).
- Hold down the combustion analysis button (CO) for at
least 4 seconds while switching electrical power back
on again.
To check that the hour counter has reset properly, switch
power to the boiler off and back on again: after all the
segments of the digital display have lit up, the display
reads out the hour count.
NOTE! Reset the hour counter every time you thoroughly
clean or replace the primary heat exchanger. To ascertain
the actual number of hours of boiler operation, multiply
the value displayed by 100 (e.g. value displayed 18 =
1800 hours operation; value displayed 1 = 100 hours
operation).
20
40 60
80
100
4
3
2 1 0
0
120
C
40
A
B
A
A
A
A
CO
B
A
A
A
Summary of Contents for 20044966
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