Flame Presence Check; Burner Operation; Residual Flame - Riello RS 70 VA Installation, Use And Maintenance Instructions

(A)
(B)
STANDARD IGNITION
IGNITION FAILURE
20

BURNER OPERATION

BURNER START-UP (A)
• Control remote control TL closes.
• 3 sec.: fan motor starts.
• Servomotor starts: rotate right 90° in 30 sec to
reach its maximum opening
• 33 sec.: pre-purging stage with MAX output
air delivery. Duration 37 sec.
• 70 sec.: the servomotor rotates towards the
left until the angle set on the orange cam.
Duration 25 sec.
• 98 sec.: ignition electrode strikes a spark.
• 103 sec.: pilot valves VP1 + VP2 open.
• The flame is ignited at a low output level.
Within 5 sec from the opening of the pilot
valve, the probe S01 detects the flame.
• 108 sec.: the spark goes out.
• 118 sec.: the main valves VS + VR open. The
main flame ignites, within 3 seconds (timed
value) from the opening of the main valves
the flame detection passes to S0.
• Delivery is then progressively increased, with
the valve VR opening slowly up to MIN. out-
put, point B.
• The control value box starting cycle ends.
STEADY STATE OPERATION (A)
Burner without the output power regulator
RWF
Once the starting cycle has come to an end,
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control of the servomotor passes on to the
remote control TR that controls oven tempera-
ture, point C. (The electrical control box still con-
tinues to check the presence of the flame and
the correct position of the air and gas maximum
pressure switches).
• If the temperature is low, so the remote con-
trol TR is closed, the burner progressively
increases the output up to the MAX value
(tract C-D).
• If the temperature increases until the opening
of TR, the burner progressively reduces the
output up to the MIN value (tract E-F). The
sequence repeats endlessly.
• The burner locks out when heat request is
less than the heat supplied by the burner at
MIN output, (tract G-H) and the remote con-
trol TL opens.
Burner with the output power regulator RWF
See the handbook enclosed with the regulator.
IGNITION FAILURE (B)
If the burner does not switch on, the gas valve
goes into lockout within 5 s of the opening.
If there is no ignition due to a lack of reading
from the SO sensor, increase the ignition power
using the orange cam, taking it to 30°- 35°.
BURNER FLAME GOES OUT DURING OPER-
ATION
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If the flame should go out during operation, the
burner will lockout within 1s.

RESIDUAL FLAME

When the burner switches off, there may be a
residual flame for a few seconds if the length of
the head/spacer is notable. To resolve this situa-
tion, enable the post-purging function by power-
ing the fan motor or the relative contactor via
clamp 7 of the control box (instead of clamp 6,
as shown in the diagram on sheet 3 of this man-
ual).