AERMEC FCL Series - Electric Heater and Ventilation Logic

53
In the 2-pipe configuration the heating mode is activated by controlling the general solenoid valve
Y1, while in the 4-pipe configuration the heating water solenoid valve Y2 is controlled with the
same logic, and closing the cooling water valve (that in the 4-pipe case is Y1) as soon as the
heating mode is imposed.
Configuration with electric heater
If the system has an electric heater, the only fan operating speeds allowed will be the maximum
(V
3
) and medium (V
2
). The dip-switches determine whether a supplementary or replacement
electric heater is active:
 supplementary: the electric heater is activated at the same time as the heating water valve,
to increase the efficiency of the machine. Or, if there is not enough water, the electric
heater is activated to make up for the shortage of water.
 Replacement: the electric heater is only activated to make up for the shortage of heating
water.
T
SA
1,5 °C 1,5 °C
V
3
V
2
Y1 (Y2)
RE
T
L
0,6 °C
Se dip 6 di SW 1 è
off la ventilazione è
sempre attiva
Se dip 1 di SW 1 è off
(integrazione) si attiva la
resis tenza
heating mode, with electric heater and fan in automatic mode
In each of the heating modes described above, if the ventilation is measured by a thermostat (dip 5
of SW1 is ON), the fan will not be switched on instantly when suitable conditions are obtained, but
will follow the timed setting described in:
Thermostat-controlled heating ventilation: pre-heating of coil and Thermostat-controlled
heating ventilation: pre-heating of electric heater.
Safety thermostat on the electric heater
Initially, after waiting 1' and a half minutes, the software checks that the electric heater reaches at
least 50° (otherwise an electric heater absence alarm is indicated).
The control software verifies the temperature of the electric heater via the NTC: if the temperature
detected is over 160°C, it cuts off the power supply, and this is reset when the NTC electric heater
falls below 140°C
1
. After the power supply has been interrupted for two minutes, the alarm counter
is increased; the alarm counter
is also increased for every subsequent minute of interruption to the
power supply. The counter is decreased after 5 minutes from the moment it began to increase.
When the alarm counter reaches position 3, the system goes into alarm lock mode.
1
With reference to the datasheet of the Shibaura temperature probes equipped with PSB thermistor with a
G-type heater-temperature curve: about 10 Kohm are equivalent to 160°C and 18 Kohm to 140°C