baltur 17830010, Installation, Use And Maintenance Instruction Manual

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ENGLISH
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• If necessary, correct the combustion air supply adjusting the
screw(s) (11) as described previously.
• Check the combustion parameters in the 1st stage with
appropriate instruments (CO2 MAX=10% O2 MIN= 3% CO
MAX=0.1%)
• The air pressure switch prevents the opening of the gas valves
if the air pressure is not the foreseen one. The pressure switch
must therefore be adjusted to intervene closing the contact
when the air pressure in the burner reaches a sufficient value. If
the air pressure switch does not detect a pressure greater than
that calibrated, the equipment runs through its cycle but does
not switch on the ignition transformer and the gas valves do not
open, consequently the burner “locks-out”. To ensure correct
operation of the air pressure switch you must, with burner lit
and in first stage, increase its regulation value until the burner
triggers after which it must immediately “lock out”. Release the
burner by pushing the appropriate button (9) and readjust the
pressure switch to a sufficient value to detect the existing air
pressure during the pre-ventilation phase of the first stage.
• The gas control pressure switch (minimum) prevents burner
operation when gas pressure is not the foreseen one. The
minimum pressure switch must use the contact that is closed
when the pressure switch detects a pressure higher than the
value it is set to. The minimum pressure switch regulation
must be done upon burner start-up according to the pressure
detected each time. The triggering (opening of the circuit) of any
of the pressure switches when the burner is running (flame on)
causes the burner to stop immediately. Upon first ignition of the
burner, it is essential to check that it works properly.
• Check for the triggering of the ionisation electrode by
disconnecting the jumper between terminals 30 and 31 on the
printed circuit board and start the burner. The equipment must
run through its cycle completely and, three seconds after the
ignition flame has formed, “lock-out”. This check should also
be carried out with the burner already lit. The apparatus should
lock out immediately when the jumper between terminals 30
and 31 is disconnected.
• Check for the efficiency of the thermostats or boiler pressure
switches (they should shut down the burner when triggered).
Check that the ignition takes place properly. In the event that
the mixer is too far forward, it may happen that the speed of the
delivery air is so high that ignition is difficult. If this happens, the
mixer must be gradually shifted back until it reaches a position
in which ignition occurs regularly, and this position can be
regarded as the final position. For the first stage, it is preferable
to limit the quantity of air to that which is strictly necessary for
safe ignition, even in the most difficult circumstances.
DANGER / ATTENTION
Once the adjusting operations are completed, visually
check that the thin plate on which the bearing acts has a
progressive profile. Also check trough the dedicated tools
that during the passage between first and second stage the
combustion parameters do not excessively vary from the
optimal values.
POWER AT START-UP
The standard EN 676 prescribes that for burners with maximum
output above 120 kW the ignition must occur at a reduced power
Pstart than the maximum power of operation Pmax at which the
burner is calibrated.
Pstart depends on the safety time of the burner equipment; in
particular:
ts = 2s → Pstart ≤ 0.5 x Pmax .
ts = 3s → Pstart ≤ 0.333 x Pmax .
Example if the maximum regulation power of the burner Pmax is
equal to 900 kW, it must be:
Pstart ≤ 450 kW where ts = 2s
Pstart ≤ 300 kW where ts = 3s
Check power at ignition
• Disconnect the flame sensor wire (in this case the burner
turns on and goes into lock-out after the safety time ts).
• Perform 10 consecutive ignitions and following block.
• Measure at the meter the amount of gas burned Qstart [m³]
and check that Qstart ≤ Pmax /360 ( in m³/h)
Example
Pmax = 90 m³/h (about 900 kW with natural gas)
After 10 ignitions with the related lock out, the gas consumption
read on the meter must be:
Qstart ≤ 90/360 = 0.25 [m³]
If this does not occur, reduce the flow of gas to the ignition through
the brake of the valve.