baltur TBML 160 PN, Manual Instructions For Use

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0006081428_201406
ENGLISH
DESCRIPTION OF OPERATION
WITH GASEOUS FUEL
After closing switch 1, if the thermostats are closed, the voltage
reaches the command and control equipment (switching on LED 2)
which starts it working. The fan motor is thus switched on to carry
out preventilation of the combustion chamber, at the same time the
air shutter control servomotor moves to the opening position corre-
sponding to the maximum power setting.
At the end of the preventilation stage the air shutter goes back
to the ignition flame position. If the air ventilation control pressure
switch has found that there is sufficient pressure, the ignition trans-
former will start (LED 4) and, two seconds later, the safety and
main valves will open (LED 5).
In particular:
• The main valve has a device to proportionally adjust the air/
gas ratio.
• The safety valve is an ON/OFF type.
• The air shutter is activated by an electric servomotor (see ad-
justment 0002933651), remember that when the burner stops
because the thermostat is triggered, the shutter is returned by
the servomotor to the closed position.
! The flow rate of gas in the ignition flame
position should generally be greater than the
minimum flow modulation. The ignition flame
position can be adjusted using the air shutter
control servomotor (see 0002933651).
The flame is detected by the control device and allows the equip-
ment to proceed to the ignition stage with the switching off of the ig-
nition transformer. Then the servomotor opens the air shutter grad-
ually and the pneumatic valve allows an increase in the gas flow up
to the maximum set value.
If there is no flame, the appliance shuts down in “safety lock-out”
mode (LED 7 on) within 3 seconds of the opening of the main
valve. In safety lock-out mode the valves are closed again immedi-
ately. To release the equipment from this safety position, press but-
ton 8 on the display panel.
MODULATION OPERATION
DESCRIPTION
When the burner is ignited at the minimum setting, if the modulation
probe allows it (adjusted to a temperature or pressure which is
greater than that present in the boiler) the air adjustment servomotor
begins to function,
causing a gradual increase in the combustion air flow and
consequently of the gas, until it reaches the maximum flow setting
on the burner. The increase in ventilator air pressure is detected by
the proportional gas valve sensor, which gradually adjusts the gas
flow to the air pressure variation, which is also gradual. The burner
remains in the maximum flow position until the temperature or
pressure is high enough to trip the modulation probe, which reverses
the rotation of the air adjustment servomotor.
Reverse rotation of the servomotor, and consequently a reduction in
gas and air flow, is effected in a series of short steps. By this method,
the modulation system operates to bring the amount of heat supplied
to the boiler in line with the heat that the boiler puts out to service.
The modulation probe installed on the boiler measures any variation
requests and automatically adjusts fuel and combustion air supply,
by starting the air adjustment servomotor and increasing or reducing
rotation as necessary. If the limit value (temperature or pressure)
at which the stop device is set (thermostat or pressure switch) is
reached even with gas supply at minimum level, the burner is shut
down by the device.
When temperature or pressure returns below the shut-down device
tripping value, the burner is activated once again according to the
program described in the previous section.
1 Main switch ON - OFF
2 Power LED
3 Fan LED
4 Transformer ON LED
5 2
nd
stage LED
6 1
st
stage LED
7 Appliance shutdown LED
8 Appliance unlock button
9 Fuel fill button
10 Fuel switch