REMEHA Selecta - 11 SERVICE & MAINTENANCE; 11.2 Inspection; 11.2.1 Checking the boiler combustion

Remeha Selecta
50
11 SERVICE & MAINTENANCE
11.1 General.
The Remeha Selecta has been designed to need minimum maintenance, but to
ensure optimum efficiency we advise that once a year the boiler should be checked
and if necessary cleaned and reset.
All service and maintenance must be carried out by a qualified Engineer with the rel-
evant training and certification (ie CORGI - ACS -IEE registrations etc.).
11.2 Inspection
The annual inspection of the Remeha Selecta can be limited to:
- Checking the boiler combustion
Note: Check the boiler for correct gas/air setup in full load by measuring the O
2
levels
in the flue gas (direct measurement of CO
2
can lead to inaccuracies due to varying
levels of CO
2
in the natural gas)
- Check/clean the condensate siphon (refill with clean water).
- Checking/clean the ignition electrode; gap adjustment (3 - 4 mm) replacing the gas-
ket if necessary
- Check ignition probe earthing.
- Check the ionisation current with a DC voltmeter between terminal 4 on the green
X4 plug and a suitable earth connection.
Note: The maximum ionisation current is 9µA and any reading lower than 4µA will indi-
cate that the electrode will require replacement
- Check for leaks (water side and gas soundness).
- Checking the water pressure
- Check flue and air inlet system is clear and gas/water tight.
- Check safety controls
- Check control settings.
- Check boiler parameters
- Is flame shape stable and colour as described in Par. 11.2.2
- Check temperature sensors for resistance values against Fig. 30 (humidty on sensors).
11.2.1 Checking the boiler combustion
This can be done by measuring the CO
2
/O
2
percentage via the flue gas measuring
point in the flue of the boiler.
To do this, fire up the boiler to a water temperature of approximately 70°C. If this check
shows that the combustion of the boiler is outside of the tolerances indicated in Table
12, clean it according to the instructions in Par 11.3. If, after cleaning, the combustion
of the boiler is still outside of the tolerances, then adjust CO
2
/O
2
percentage according
to the instructions in Par. 11.2.2.