baltur TBG 85 MC, Installation, Use And Maintenance Instruction Manual

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ENGLISH
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OPERATING DESCRIPTION
The gas train supplied is composed of an ON/OFF safety valve and a
single stage slow opening main valve.
The fuel flow rate regulation in the first and second stage is carried
out by a streamlined butterfly valve -6, activated by the electric
servomotor -7 .
The movement of the air shutter -8 is produced by the rotation of
the servomotor -7 through a lever and strap system -34. **inserire-
traduzione** When the main switch -1 turns on, if the thermostats are
on, voltage reaches the control box which starts the burner -2.
This turns on the fan motor -3 for pre-ventilation of the combustion
chamber. The rotation of the control servomotor -7 occurs at the same
time and brings the gas throttle -6 and the air shutter -8 in the opening
position corresponding to the second flame, by leverage.
The preventilation phase comes only with the air gate in the second
flame position.
At the end of pre-ventilation, the gas throttle and the air shutter are
returned to the ignition position, then the ignition transformer turns on
and the gas valves open.
The presence of the flame, detected by the control device, permits
continuation and completion of ignition, turning off the ignition
transformer.
1 Main on/off switch
2 Thermostat on indicator light
3 Fan motor indicator light
4 Ignition transformer indicator light 5 Gas valves' indicator light
9 Reset button
10 Lock-out indicator light
Then, the passage from minimum to maximum output takes place
through the progressive opening of the gas throttle and of the air
shutter at the same time.
At the moment in which the demand for heat from the system is
satisfied, the boiler thermostat will intervene and shut down the boiler.
The air shutter, through the rotation of the servomotor, will reach the
closed position when inactive.
In the event that the control device does not detect the presence
of a flame, the control box activates a “safety lock-out” -10 within 3
seconds of the opening of the main gas valve. In “safety lock-out”
mode the valves are immediately closed again. To reset the control
box from its safety position, press the reset button -9.
MotReg_
002
7
6
8
34
MODULATION OPERATION DESCRIPTION
When the burner is on at minimum flow rate, if the modulation probe
allows it (set to a temperature or pressure value higher than that in the
boiler) the air/gas regulation servomotor starts turning;
• in a clockwise direction the air flow increases;
• anticlockwise rotation: the air flow decreases.
thus gradually increasing gas supply and combustion air until the
maximum supply level set for the burner is reached.
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.
The inverse rotation and therefore the air and gas supply reduction
occurs shortly thereafter.
With this procedure, the modulation system attempts to balance the
amount of heat supplied to the boiler with respect to the amount the
boiler releases for use.
The modulation probe installed on the boiler measures any variation
requests and automatically adjusts fuel and combustion air supply, by
starting the air/gas regulation 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.