Alfa
33
hot air gas-
fi
red air heaters
In support of engineering, installation, servicing, and maintenance
52.10.03.2017.eng
Only a Lersen brand service centre may carry out the capacity setting. Correct
combustion cannot be set without
fl
ue gas analyser.
1. Set the SM selector (inside the unit) to the MANUAL position.
2. Set the rated of the Alfa TOP unit (burner) with the High adjustable resistor
(position A) on the modulation board. Figure 2. The unit capacity (premix fan
speed) increases by turning the control clockwise, decreases by turning it counter
clockwise. Use this adjustable resistor to set the maximum rated capacity as
described on page 6 hereof (table of Technical Parameters). Maximum rated input
matches the stabilized
fl
ue temperature of 200°C at ambient temperature 18°C.
3. Adjust the mixture saturation level and
fl
ue gas value, using the adjustment
screw in the premix burner Venturi tube while watching the reading of the
fl
ue
gas analyser.
4. Set the push-button inside the unit to the MODULATION position
5. With the High value set, the Low value must be adjusted as well. The value
poses the % by which the premix fan speed falls down at most. Thus, the rated
capacity min is determined as described on page 6 hereof (table of Technical
Parameters). Recommendable drop in the equipment capacity is not more than
30% of the High set value.
6. Based on the
fl
ue gas temperature, modulation setting is to be carried out
with TEMPERATURE adjustable resistor on the modulation board. Using the
fl
ue gas
analyser, determine the current
fl
ue temperature, by watching the TEMP yellow
LED. The temperature achieved will manifest itself by uninterrupted light of this
diode. By turning subsequently the adjustable resistor a short way left or right set
the point where a correct temperature can be foreseen. Leave the unit running
and follow the
fl
ue gas analyser to
fi
nd out if the temperature ranges around its
selected value. If not, turn the TEMPERATURE adjustable resistor a bit more until
the ideal condition is achieved.
Input IN
a. IN= 0 No modulation, manual mode, High speed can be set.
b. IN 0 » 1 There is no modulation within 120 seconds from change in status,
High speed can be set.
Modulation takes place within 120 seconds from change in status, depending
on the set temperature.
c. IN 1» 0 Equipment restart will occur, then, after 120 seconds, followed by
return to the High position. No modulation will take place for 120 seconds and the
High speed can be set.
Modulation board indicator lights
PWR (green)
Lit while the main power supply is connected to the modulation board
IN (red)
Lit – indicating the MODULATION status
O
ff
– indicating the MANUAL status
TEMP (yellow)
Long
fl
ashing – temperature achieved is below setpoint
Short
fl
ashing - temperature achieved is above setpoint
Lit - temperature achieved as approximately equal to the setpoint (di
ff
erence
not more than 5 °C) Noti
fi
cation:
Polarity must be observed when the thermocouple is being connected. The
equipment is unable to detect short or open circuit thermocouple for thermostat.
Alfa TOP and ECO: How to Set
Capacity
Modulation Board Functions
fi
g.2
Indikace
PWR
Indikace
IN
Indikace
TEMP
240 °C
50%
140 °C
100%