baltur Minicomist 7, Installation, Use And Maintenance Instruction Manual

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0006081159_201602
ENGLISH
IGNITION AND ADJUSTMENT
WITH DIESEL FUEL
• Make sure that motors (fan and pump) turn in the right direction.
• Make sure that the discharge of combustion products can take
place freely (chimney gates should be open) and that there is
water in the boiler.
• Open the combustion air regulator as necessary and open the
air passage between the head and the disk by about a half,
using the adjusting screw of the flame disk.
• Close the main switch and the burner switch to activate the
burner and wait for it to start. The burner is therefore activated
and carries out the preventilation phase.
If the air pressure
exceeds the value at which the air pressure
switch has been set
, the diesel fuel valve will be activated.
With the burner on, adjust combustion air delivery, if necessary.
• The burner is equipped with a device which optimises
combustion by decreasing and increasing the air flow between
disk and head. The maximum smoke rate allowed is No 2 of
Bacharach scale, with a carbon dioxide value (CO2) ranging
from 10 to 13%. Usually, you need to decrease the air flow
between disk and head when the burner works with reduced
fuel delivery. The air flow must be proportionally larger when the
burner works with an increased fuel delivery. Use the flame disk
adjusting screw to adjust air flow. When modifying this position,
it is necessary to check that ignition occurs correctly.
IGNITION AND ADJUSTMENT
WITH METHANE GAS
In order to proceed with ignition, it is necessary to vent the air
contained in the pipeline and to check, in case of a three-phase
burner, that the motor rotates in the right direction. Then proceed
as follows:
• Make sure that the discharge of combustion products can take
place freely (chimney gates should be open) and that there is
water in the boiler.
• Open the combustion air regulator as necessary and open the
air flow between head and disk by one third using the adjusting
screw of the flame disk.
• Use the regulators incorporated in the gas valves in such a way
as to obtain the gas delivery presumed necessary.
! See the specific table for the gas delivery adjustment based
on the type of valves fitted on the burner page 17.
• Power the burner by turning on the main switch and the
burner switch. The burner is therefore activated and carries
out the preventilation phase.
If the air pressure
exceeds the value at which the air pressure
switch has been set
, the ignition transformer activates
and, subsequently, the gas valves activate as well.
The safety valve opens completely whereas the main valve that
incorporates the adjustment elements opens in two stages. The
first opening stage carries out the trigger flow rate and occurs
instantaneously. The second opening stage occurs gradually and
at the end of it, the burner is at the maximum flow rate permitted
by the position set on the maximum flow rate regulator. On first
switching on, repeated “lock outs” may occur due to:
- The gas piping not being vented of the air sufficiently, so that
the gas flow is insufficient to ensure a stable flame.
- The “lock out” with flame present may be caused by flame
instability, due to an incorrect air/gas ratio. This can be solved
by changing the amount of air and/or gas supplied, so as to
find the right ratio. This problem may also be caused by a
wrong air/gas distribution in the combustion head. This can be
solved using the combustion head adjusting device by further
closing (loosening the adjusting screw) or opening (tightening
the adjusting screw) the air flow between combustion head
and gas diffuser. To adjust it, use the flame disk adjusting
screw.
• With the burner running, adjust delivery to the value corresponding
to the desired capacity (methane = 8550 kcal/m
3
) by reading
the meter. This flow rate can be changed using the regulator
incorporated in the valve, as described above.
• Make sure that combustion is carried out correctly by means of
the relative instruments. Maximum carbon oxide (CO) allowed =
0.1 % with carbon dioxide value (CO
2
) ranging from 8 to 10%.
• After this adjustment, switch off the burner and start it again for
a few times to check if ignition is correct.
SAFETY CHECKS
After adjustment, always check that:
• the burner stops "opening" thermostats and air and gas pressure
switches.
• a "lock out” occurs when obscuring the photocell (UV).
To unlock, push the appropriate button.
UV PHOTOCELL
Even the slightest greasiness will compromise the passage of the
ultraviolet rays through the UV photocell bulb, thus preventing the
sensitive internal element from receiving the quantity of radiation
necessary for it to work properly. If the bulb is fouled with diesel fuel,
fuel oil, etc., it must be properly cleaned. It should be pointed out that
even by simply touching the bulb with fingers, it is possible to leave
a slight greasiness which could compromise UV photocell operation.
The UV photocell does not “see” daylight nor does it perceive the
light of an ordinary lamp. Sensitivity can be checked with a flame
(cigarette lighter, candle) or with the electric discharge between the
electrodes of a common ignition transformer.
To ensure proper operation, the UV cell current value should be
sufficiently stable and should not drop below the minimum value
required by the specific equipment; this value is indicated in the
wiring diagram. It may be necessary to search for the best position
by sliding (axial or rotational movement) the casing that contains the
photocell with respect to the fastening clamp. This can be checked
by connecting a micro-ammeter, with a suitable scale, in series to
one of the two UV photocell connection cables. Obviously the polarity
(+ and -) must be respected.