Immergas NIKE MINI 28 KW SPECIAL, Instruction And Warning Booklet

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INS
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MAINTEN
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CE TECHNI
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3.8 AUTOMATIC SLOW IGNITION
FUNCTION WITH TIMED RAMP
DELIVERY.
In the ignition phase the P.C.B. carries out an
increasing gas delivery ramp (with pressure
values that depend on the type of gas selected)
with preset duration. This prevents every
calibration or precision adjustment of the boiler
ignition phase in any conditions of use.
3.9 "CHIMNEY SWEEP FUNCTION"
When activated, this function forces the boiler
at max. output for 15 minutes.
In this state all adjustments are excluded and only
the safety thermostat and the limit thermostat
remain active. To activate the chimney sweep
function it is necessary to position the main
switch on Reset for a time between 8 and 15
seconds without DHW or CH requests. Its
activation is signalled by the simultaneous
flashing of the LEDs (2) and (3). This function
allows the technician to check the combustion
parameters. After the checks, deactivate the
function switching the boiler off and then on
again.
3.10 PUMP ANTI-BLOCK FUNCTION.
The boiler has a function that starts the pump at
least once every 24 hours for the duration of 30
seconds in order to reduce the risk of the pump
becoming blocked due to prolonged inactivity.
3.11 THREE-WAY ANTI-BLOCK
FUNCTION.
Both in “domestic hot water” and in “domestic
hot water-central heating” phase the boiler is
equipped with a function that starts the three-
way motorised group 24 hours after it was last
in operation, running it for a full cycle so as to
reduce the risk of the three-way group becoming
blocked due to prolonged inactivity.
3.12 RADIATORS ANTI-FREEZE
FUNCTION.
If the system return water is below 4°C, the boiler
starts up until reaching 42°C.
3.13 P.C.B. PERIODICAL SELF-CHECK.
During functioning in heating mode or with
boiler in standby, the function activates every 18
hours after the last boiler check/power supply. In
case of functioning in domestic hot water mode
the self-check starts within 10 minutes after the
end of the withdrawing in progress, for duration
of approx. 10 seconds.
N.B.: during self-check, the boiler remains off,
including signalling.
3.14 YEARLY APPLIANCE CHECK AND
MAINTENANCE.
The following checks and maintenance should
be performed at least once a year.
- Clean the flue side of the heat exchanger.
- Clean the main burner.
- Visually check the draught-breaker/anti-wind
device for deterioration or corrosion.
- Check ignition and operation.
- Check correct calibration of the burner in
domestic hot water and central heating phases.
- Check the operation of the appliance control
and adjustment devices and in particular:
- intervention of the main electrical switch on
the boiler;
- system control thermostat intervention;
- domestic hot water control thermostat
intervention.
- Check that the internal system is properly
sealed according to specifications.
- Make sure the ionisation flame control gas
supply failure safety device is working. It must
start-up in less than 10 seconds.
- Visually check for water leaks or oxidation
from/on connections.
- Visually check that the water safety drain valves
is not blocked.
- Check, after discharging the system pressure
and bringing it to zero (read on boiler pressure
gauge), that the expansion vessel charge is at 1.0
bar.
- Check that the system static pressure (with
system cold and after refilling the system by
means of the filling valve) is between 1 and 1.2
bar.
- Visually check that the safety and control
devices have not been tampered with and/or
shorted, in particular:
- over-temperature safety thermostat;
- system pressure switch;
- flue thermostat.
- Check the condition and integrity of the
electrical system and in particular:
- electrical power cables must be inside the
fairleads;
- there must be no traces of blackening or
burning.