REMEHA Avanta Plus 24s, Installation And Service Manual

Page: 51 / 153

51
é 3
Control unit or
earth fault.
Mains supply not correctly
earthed.
Control unit faulty.
Check that the power supply from the switch spur is properly
earthed, if that is the case the control unit is faulty.
é
4
More than 5 start
attempts without
any flame forma-
tion.
No ignition spark.
Check:
•
the connection between the ignition wire and the ignition trafo;
•
the ignition wire and electrode for ‘dielectric breakdown’;
•
the inter-electrode distance, this should be 3-4 mm; that
the ignition electrode is properly earthed.
A spark but no flame. Check that:
• the gas tap is open;
• the gas pre-pressure is sufficient;
• the gas pipe is de-aerated;
• the gas valve is energised during ignition and opens;
• the electrode is correctly fitted and clean;
• the CO
2
adjustment at low and full load;
•
there is no obstruction / fitting fault in the gas pipe;
•
there is no obstruction in the air supply or flue (e.g. a
blocked siphon); there is no recirculation of flue gasses
(either inside or outside the boiler).
There is a flame but no, or
insufficient ionisation (lower
than 3 or higher than 9
μ
A).
Check:
•
the flame, is the heart of the flame visible and the flame
stable?
•
the CO
2
adjustment at low and full load;
•
that the ignition electrode is correctly earthed;
•
visual check of the ignition/ionisation electrode: look for
white oxide film (remove with sandpaper or a
screwdriver); look at the shape (are the pins still the
original shape and is the distance between the two ends
of the pins between 3 and 4 mm).
é
5
No ionisation or
ionisation failure
more than 5
times during one
heat demand.
CO
2
wrongly adjusted. Check:
• CO
2
adjustment on the gas block;
• ignition/ionisation pin;
• flue/air-supply connections;
• gas flow at full load;
•
if there is no recirculation of flue gasses (either inside or
outside the boiler).
é 6
Unwanted flame
formation.
Faulty control unit, replace control unit.
é
7
No water in the
boiler or the
pump is not
working.
Insufficient water.
Check the minimum water pressure, read off the gauge and check
for leaks.
No through flow.
Check that the pump is working; turn the spindle with a screwdriver,
if that works but the pump still does not respond, check the wiring;
that is in order the pump is faulty.
Too much air in the system. Vent the system.
Wrong pump wiring.
Check wiring from and to control unit.
é 8
Fan fault.
Fan is not working. Check:
•
fan function;
• fan wiring and connection.
Fan does not stop. Check:
• fan function;
• fan wiring and connection;
• excess chimney draught.
Error
code Description Possible cause Check / solution