20017633
15
GB
6.2
OPERATING IRREGULARITIES
The burner locks out
during the prepurge
phase.
The air pressure switch does not
change over to the operational posi-
tion.
The pressure switch is faulty, change it.
The air pressure is too low, (the head is
bad adjusted).
The flame exists.
Faulty valves: replace them.
The pressure test point (13, fig. 9,
page 9) is badly positioned.
Place it in the right position according to
the instructions of this manual on page
9, chapter 4.2.
The burner continues
to repeat the starting
cycle without going on
lock-out.
The gas pressure in the gas-mains
lies very close to the value to which
the gas pressure switch has been set.
The sudden falling-off pressure at the
opening of the valve causes the
opening of the pressure switch. How-
ever this only temporarily, because
the valve immediately closes again,
so then does the pressure switch, be-
cause the pressure builds-up again,
causing the cycle to be repeated
over and over.
Lower and set the pressure switch.
Burner tends to pull the
flame when switching
from 1
st
to 2
nd
stage.
Output ratio between 1
st
and 2
nd
stage
greater than 1:2.
Restore correct maximum ratio of 1:2,
making sure 1
st
stage output is no less
than the operating range's minimum.
High air excess in 1
st
stage.
Restore the correct air excess value (
min. = 1.3) see section “4.4 combustion
control”.
FAULTS
POSSIBLE CAUSES
SOLUTION
The burner locks out
during operation.
Earth probe.
Check the right position and if necessary
set it according to the instructions of this
manual.
Clean or replace the ionization probe.
The flame disappears 4 times.
Check the gas pressure in the network
and/or adjust the solenoid valve accord-
ing to the instructions of this manual.
Air pressure switch opening.
The air pressure is too low, (the head is
bad adjusted).
The air pressure switch is faulty,
change it.
Burner shut down.
Gas pressure switch opening.
Check the pressure in the network and/or
adjust the solenoid valve according to the
instructions of this manual.
FAULTS
POSSIBLE CAUSES
SOLUTION