Technical documentation
Technical documentation
STESP ed 02/02
15
EOLO SUPERIOR PLUS
LOADS
3-way electric valve
(VD)
Deviates the flow of water of the primary circuit from the heating circuit to the boiler coil
and vice versa.
It is powered by the modulation card.
Circulator
(MP)
Permits circulation of water in the primary circuit.
This is powered by the modulation board whenever there is a demand for d.h.w.,
heating or antifreeze.
Fan (MV)
Ensures the flow of air inside the sealed combustion chamber and the exit of fumes
produced by combustion.
Powered by the modulation board.
Gas valve (VG)
(main coils)
This is powered by the ignition control unit when the burner has to be ignited.
Permits flow of gas to the burner.
Ignition control unit
(IGN. CARD)
Controlled by the modulation board when the burner has to be ignited.
Controls the devices needed for ignition
(gas valve, ignition electrodes)
and flame detection
(ionisation electrode).
Ignition electrodes
(E1 - E2)
These provoke an electric spark that ignites the air/gas mix.
They are controlled by the control unit ignition transformer (IGN. CARD)
Modulation card
This is powered when the main switch (IG) is positioned in
(summer or CAR)
or
(winter) (see modulation board operation).
LOW-VOLTAGE CIRCUIT
SAFETY DEVICES AND CONTROLS
Central-heating sensor
(NR)
Allows the modulation board to detect the temperature of the primary
circuit water flow.
If this sensor stops working, burner operation stops both in central-
heating and d.h.w. modes.
It is positioned at the outlet of the main exchanger.
Sensor NTC
10 kohm 25 ºC
Control zone unit (CZ)
(external optional)
Permits boiler operation with 3 area valves /external pumps controlled
by respective room thermostats.
Zone 1 is controlled
(times/temperatures)
by means of the CAR
(if
fitted).
See control unit
zone operation
Domestic hot water sensor
(NB)
This enables the modulation board to detect the temperature of the hot
water in the storage tank.
Its failure stops burner operation in domestic hot water phase.
It is fitted in a bulb holder in contact with the wall of any connected
external storage tank.
Sensor NTC
10 kohm 25 ºC
External sensor (NE)
(external optional)
Detects external temperature and enables the modulation board to
change the system flow temperature according to outside temperature.
Sensor PTC
1 kohm 25 ºC
Flue pressure switch
(SV)
This acts on the modulation board and enables burner operation when
fume expulsion occurs correctly.
If this is closed with the fan off, the ignition cycle will not start.
2-position switch
