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STEEkW ed 12/03 EOLO Eco kW
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STEEkW ed 12/03 EOLO Eco kW
Technical Documentation
Technical Documentation
Technical Documentation
Technical Documentation
e circulator (M1) and the 3-way diverter valve (M30) are turned on for 30 seconds
after:
- 24 hours of inactivity with the main selector switch on SUMMER.
- 3 hours of inactivity with the main selector switch on WINTER.
Circulator / 3-way diverter
valve antilock
To prevent the water-gas exchanger from overheating in the case of a blocked pump or
if there is little water circulating in the primary circuit, when the NTC central heating
probe (B1) detects an increase in temperature that exceeds 5 °C/second, the burner is
switched off.
It restarts when delivery temperature drops below 43 °C.
Insufficient circulation
Breakage of the central heating probe (B1) prevents operation in the central heating phase and in the
domestic hot water phase.
Breakage of the domestic hot water probe (B2) is signalled by the flashing of Led 10 ( ), the
boiler keeps working in d.h.w. mode.
NTC probe breakage
(B1 and B2)
Safety devices.
If, within 10 seconds from the start of the ignition cycle the detection electrode (E2) fails
to detect the flame on the burner, the boiler operation is interrupted.
e integrated board makes 2 ignition attempts lasting 10 seconds with an interval of 30
seconds after which it shuts down and the function is inhibited for at least one hour; you
gain one attempt each hour up to a maximum of 5 attempts.
To restore boiler operation, turn the main selector switch (R10) round to the “Reset”
position and then make either a domestic hot water or central heating request.
Failed ignition lock
If the overheating safety thermostat contact opens, boiler operation is blocked.
To restore boiler operation, turn the main selector switch (R10) round to the “Reset”
position and then make either a domestic hot water or central heating request.
Safety thermostat lock
(E4)
To prevent the water-gas exchanger from overheating, at the end of each central heating, an-
tifreeze or “chimneysweep” request, the circulator (M1) keeps working for 150 seconds.
Post-circulation pump
After the burner has been switched off at the end of any type of request, the combustion
chamber is washed and the fan is kept running for 30 seconds.
Sealed chamber post-ven-
tilation
To prevent the water-gas exchanger from overheating, if the boiler temperature detected
by the NTC central heating probe (B1) exceeds 90 °C, the fan is switched on until the
temperature drops below 85 °C.
Delivery overheating
ventilation
If the flue pressure switch contact opens while the fan is working, the boiler is stopped.
If normal conditions are restored, the boiler restarts without having to be reset.
If it closes with the fan off, it does not enable start of the ignition cycle.
Flue pressure switch lock
(S6)
