See
The boiler service manual for the specific maintenance work. This
manual can be found on the website.
11.3.1 Preparation
Carry out the following steps before commencing inspection and
maintenance activities:
1. Set the boiler to full load until the return temperature is around 65°C,
to dry the heat exchanger on the flue gas side.
2. Check the water pressure.
The minimum water pressure is 0.8 bar. The recommended water
pressure is between 1.5 bar and 2.0 bar.
2.1. If necessary, top up the central heating system.
3. Check the ionisation current at full load and at low load.
The value is stable after 1 minute.
3.1. If the value is lower than 3 µA, clean or replace the ionisation
and ignition electrode.
4. Check the condition and tightness of the flue gas outlet and air supply
system.
5. Check the combustion by measuring the O
2
percentage in the flue
gasses.
11.3.2 Checking the water quality
The requirements for the water quality can be found in our Water quality
instructions.
Caution
Not fulfilling the water quality requirements can damage the boiler
and will void the warranty.
1. Fill a clean bottle with some water from the boiler using the filling/drain
valve.
2. Check the quality of this water sample or have it checked.
11.3.3 Checking the gas filter
The gas control valve on the boiler is fitted with a gas filter. Check the gas
filter for dirt. Proceed as follows:
Fig.109 Checking the water quality
AD-3001567-01
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11 Maintenance
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C 340 / C 640
7762666 - v.02 - 29092020
