Combustion Analysis - Vaillant ecoMAX pro Instructions For Use Installation And Servicing

15 Combustion analysis

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.
It is not necessary to check the CO
air ratio of the boiler during initial commissioning or for
the annual service.
Checking/adjustment of this value is only required in
the following instances; replacement of gas valve or
fan, conversion from Natural Gas/ LPG or if incorrect
combustion is suspected.
To carry out a combustion check, connect a CO
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 (
flashing '0' appears.
Press the '-' key and scroll through until '96' (installer
mode) is shown on the screen, then press the 'mode'
button again.
32
content or adjust the
2
2
) for 10 seconds until a
Fig 15.1
Fig 15.2
Press the '+' key and scroll through until '8' is shown on
the left of 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).
Instructions for Use, Installation and Servicing ecoMAX pro
Fig 15.3
"A" throttle –
"Pmax" rotate
to increase
"B" offset adjustment
"Pmin" rotate
to increase
Fig 15.4