Immergas EOLO Star Export Manual page 23

Technical documentation
Detection electrode
(E3)
Main switch
(IG)
Clock programmer
switch (OP)
(optional)
Absolute water pressure
switch
(SP)
Flue pressure switch
(SV)
Hot water signal
(SS)
C.H. NTC sensor
(NM)
D.H.W. NTC sensor
(NS)
Overheat. safety device
(TS)
Room thermostat (TA)
(optional)
STES ed 07/01
INPUTS
Enables the ignition circuit of the board to detect the presence of a flame on the burner.
If this does not operate, the no ignition lock trips, signalled by the lighting up of LED LD2
(red).
The eventual operation prior to burner ignition is indicated by the flashing of LED LD2 (red
This is a double switch which, depending on position, either energises or
fails to energise the low-voltage circuit and indicates whether hot water
operation is enabled (SUMMER) or hot water and heating (WINTER).
In RESET position, this releases the ignition circuit in case of tripping of
flame lock or overheating.
This is a clean contact switch controlled by a clock that enables or
disables boiler operation in heating phase during selected time intervals.
When the pressure in the heating circuit falls below 0.3 bar, it does not
enable operation of the pump (MP) and the burner.
When this switch trips, the LEDs LD1 (yellow) and LD2 (red) flash..
This provides power to the gas valve when fan operation ensures correct
fume extraction.
If this is closed with the fan off, it does not enable ignition cycle start.
This indicates the type of request under way (hot water or heating).
Depends on position of hot water flow microswitch (SS).
This is as resistance that can be varied in a way inversely proportionate to
the temperature of the supply water in the heating circuit.
Also used as limit thermostat (90 ºC).
This is a resistance that can be varied in a way inversely proportionate to
the hot water outlet temperature.
When the safety temperature is exceeded (105 ºC) this interrupts power to
the main coils of the gas valve (VG).
The tripping of this device stops boiler operation (overheating lock) and
is indicated by the flashing of red LED LD2.
This is a clean contact switch that enables operation in heating phase
when the room temperature falls below that required.
21
Technical documentation
Switch A
open= circuit OFF
closed = circuit ON
Switch B
open = SUMMER
closed = WINTER
open = heating OFF
closed = heating ON
open =
no pressure
closed =
pressure OK
open = fan OFF
closed = fan ON
open =
no hot water request
closed =
hot water request
Sensor NTC
10 kohm 25 ºC
Sensor NTC
10 kohm 25 ºC
Two-contact
clicson thermostat
open =
heating OFF
closed =
heating ON
EOLO STAR