Riello 876 T, Инструкции по установке, использованию и обслуживанию

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20168415 30 GB
Start-up, calibration and operation of the burner
6.7 Burner operation
6.7.1 Burner start-up
6.7.2 Steady state operation
Burner without output regulator
At the end of the start-up cycle, the servomotor control switches
to TR remote control that controls the pressure or temperature in
the boiler, point C. (The electric control box carries on checking
the presence of the flame and the correct position of the air and
gas maximum pressure switches).
•
If the temperature or pressure is low (so the TR remote
control is closed), the burner progressively increases the
output up to the MAX value (line C-D).
• If the temperature or pressure then increases until the TR
opens, the burner progressively decreases its output to the
MIN value (section E-F). And so on.
• The burner locks out when the heat request is less than the
heat supplied by the burner at MIN output, (section G-H). The
TL remote control opens, the servomotor returns to angle 0°
limited by the contact of cam II (Fig. 27).
The air damper closes completely to reduce heat losses to a
minimum.
With each change of output, the servomotor automatically
modifies the gas output (butterfly valve) and the air flow rate (fan
damper).
Burner with output regulator
See the manual supplied with the regulator.
6.7.3 Ignition failure
If the burner does not ignite, it locks out within 3s after the gas
valve opens and 93s after the closure of the TL remote control the
post-purging phase starts lasting 18s.
Burner flame goes out during operation
If the flame should accidentally go out during operation, the
burner will lock out within 1s.
0 s Control remote control TL closes.
Fan motor start-up.
6 s Servomotor start-up: turn to the right by 90°, i.e. until the
contact intervenes on cam I (Fig. 27).
The air damper is positioned to MAX output.
30 s Pre-purging stage with MAX output air delivery. Duration
31 s.
61s The servomotor turns to the left to reach the angle set on
cam III (Fig. 27) for the MIN output.
81 s The air damper and gas butterfly valve assume the MIN
output position with cam III (Fig. 27) at 15°.
84 s Ignition electrode strikes a spark.
90 s The safety valve VS opens, along with the adjustment
valve VR, quick opening.
The flame ignites with a small output - point A.
The output gradually increases, and the valve slowly
opens, until MIN output is reached - point B.
93 s The spark goes out.
114 s The start-up cycle ends.
Fig. 35
20156923
STANDARD IGNITION
(no. = seconds from instant 0)
Fig. 36
IGNITION FAILURE
20156924