Combustion Head; Final Checks (With Burner Operating) - Riello RX 500 S/PV Modulating Operation

6.9

Combustion head

The combustion head comprises a highly heat resistant cylinder
whose surface features numerous holes, encased in a metal
"mesh".
The air-gas mixture is pushed inside the cylinder and out of the
head through the holes in the perimeter.
Combustion starts when the air-gas mixture is ignited by a spark
generated by the electrode.
The metal "mesh" is the combustion head's most essential ele-
ment since it improves burner performance considerably.
The flame developed on the surface of the head is perfectly re-
tained and adheres to the mesh when operating at the maximum
setting.
6.10

Final checks (with burner operating)

 Open the thermostat/pressure switch TL
 Open the thermostat/pressure switch TS
 Turn the gas maximum pressure switch knob to the mini-
mum end of scale position (where present)
 Turn off the burner and cut off the power
 Disconnect the minimum gas pressure switch connector
 Disconnect the wire of the ionisation probe
Make sure that the mechanical locking systems
on the various adjustment devices are fully tight-
ened.
WARNING
20138630
Start-up, calibration and operation of the burner
This allows modulating ratios as high as 6:1, avoiding the danger
of flashback when modulating is at its minimum.
The flame features an extremely compact geometry, meaning
that there is no risk of contact between the flame and parts of the
boiler, consequently eliminating the possible problem of poor
combustion.
The flame's structure means that smaller combustion chambers
can be developed, designed to exploit this particular feature.
Before starting up the burner, it is good practice to
adjust the gas train so that ignition takes place in
conditions of maximum safety, i.e. with gas deliv-
ery at the minimum.
CAUTION

The burner must stop

The burner must stop in lockout

The burner must not start

The burner performs the ignition cycle again
34 GB
Tab. T