Vaillant ecoMAX pro 18E, Instructions For Use Installation And Servicing

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Instructions for Use, Installation and Servicing ecoMAX pro
31
Combustion analysis 15
Note!
The boiler is fitted with a combustion analysis
test point. A suitable combustion analyser
can be connected to this point to establish the
combustion performance of the boiler.
Check CO2 content, refer to table 15.1 and if necessary
set (air-ratio adjustment).
Combustion analysis must be carried out at annual
service if a flue gas analyser is available, if no analyser
is available then visual checks should be carried out as
per service schedule. Checking/adjustment of this value
is also required in the following instances: replacement
of gas valve, conversion to or from natural gas/LPG or if
incorrect combustion is suspected!
To carry out a combustion check, connect a CO
2
combustion analyser to the test point on the flue adaptor.
Turn on the gas service cock.
Turn on the electrical supply, and slide the on/off control
down to the ‘I’ position to turn on the boiler. Set the timer
to continuous and turn up any room thermostats to call
for demand.
With the boiler interface in normal operating mode, press
and hold the ‘mode’ button ( ) for 10 seconds until a
flashing ‘0’ appears.
Press the ‘+‘ key and scroll through until ‘8’ is shown on
the left of the screen, then press the ‘mode’ button again.
Fig 15.3
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Fig 15.2
12703
Fig 15.1
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Press the ‘-‘ key and scroll through until ‘96’ (installer
mode) is shown on the screen, then press the ‘mode’
button again.
Set the appliance fan speed/burner to maximum by
pressing the ‘+’ key until ‘2’ (burner to Pmax) is shown
on the right hand side of the screen. Press the ‘mode’
button again to confirm.
Check the CO2 value, which should be 8.8 % ± 0.2
%. Note that with the inner case front panel fitted the
combustion reading will increase slightly to
9.0 % ± 0.2 %. Allow the boiler time to reach the
maximum rate (approximately 5-10 minutes).
If adjustment proves necessary then proceed as follows.
Any adjustment to be the gas valve should only be
carried out by a qualified person. Adjust the maximum
rate CO2 with the (‘A’) throttle using a screwdriver to 8.8
% (rotate anti-clockwise to increase).
"A" throttle –
"Pmax" rotate
to increase
"B" offset adjustment
"Pmin" rotate
to increase
Fig 15.4
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