Ariston 47-116-49 Installation And Servicing Manual Download Page 35

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COMMISSIONING

Combustion checking procedure
The order of operations for this procedure must always be
respected.
Refer to Technical Bulletin 143 on Gas Safe Register website for
further information on combustion analysis of domestic boilers.

Operation 1 - Supply pressure check
Loosen the screw 1 and insert the pressure gauge connection
pipe into the pipe tap.
Switch the boiler on at maximum power.
To activate combustion test function:
- Press the mode selector to ensure the

icons displayed.

- Press & hold the reset button for 10 seconds. ‘

’ will

appear on the screen. Ensure the boiler is on max power by
pressing the button 2

The supply pressure should correspond to the value established
in relation to the type of gas ,for which the boiler is designed see
Table summarising changes.
Note:
The absolute minimum working pressure measured at the inlet
test nipple on the gas valve is 17.5 mbar.

Operation 2 - Preparing the measuring equipment
Connect the calibrated flue gas analyser to the left-hand
combustion outlet by unscrewing the screw and removing the
blanking cover.

Operation 3 - Adjusting the CO2 at maximum gas flow rate
(domestic hot water)
Draw off the domestic hot water at the maximum water flow rate
(if a combi).
Select the Test function by pressing the

RESET button for 10 seconds.
WARNING! When the cleaning function is activated, the
temperature of the water coming out of the boiler may be
more than 65°C.

On the display appear

and the icon

. The boiler is foced to the maximum

heating power.

Press the 2

button to forced the boiler at

the maximum DHW power. On the display
appear the icon

Wait 1 minute for the boiler to stabilise before
carrying out the combustion analyses.

Read the CO2 value (%) and compare it with the values given in
the table below

N.B.: VALUES WITH THE CASING CLOSED.

If the CO2 value (%) read differs from the values given in the
table, then adjust the gas valve following the instructions below,
otherwise move directly onto operation 4.

Adjusting the gas valve at maximum gas flow
Adjust the gas valve by turning setting screw 4 clockwise in
increments to reduce the CO2 level (a 1 turn adjusts the CO2
level by approximately 0.2%). Wait 1 minute after each change in
setting for the CO2 value to stabilise.

If the value measured corresponds to the value given in the
table, max adjustment is complete, otherwise start the setting
procedure again.
N.B. The Test function is automatically deactivated after 10
minutes or manually by briefly pressing the RESET button.
Operation 4 - Checking the CO2 at minimum gas flow
With the Test function active, press the 2

button to select the icom

and

. The boiler is forced to the minimum power.
Wait 1 minute for the boiler to stabilise before
carrying out the combustion analyses.
If the CO2 value (%) read differs by 0.5 %
from the value found, then adjust the gas valve following the
instructions below, otherwise move directly onto operation 5.

Adjusting the gas valve to minimum gas flow
Remove cap and adjust screw 2 by turning anti-clockwise in
increments to reduce the CO2 level. Wait 1 minute after each
adjustment for the CO2 value to stabilise.
WARNING! this adjustment is sensitive: a rotation of a 1 turn
corresponds to 0.2% of CO2.