Ariston Clas 24 FF, Инструкции по установке и обслуживанию

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34
boiler protection devices
Anti-frost Device.
The anti-frost function acts on the central heating fl ow temperatu-
re probe, independently from other regulations, when the electri-
cal supply is turned on.
If the primary circuit temperature falls below 8°C the pump will
run for 2 minutes.
After the two minutes of circulation (fi xed) the boiler will check
the following:
a) if the central heating fl ow temperature is > 8°C, the pump
stops;
b) if the primary fl ow temperature is between 4 and 8°C, the pump
will run for another two minutes;
c) if the primary fl ow temperature is < 4°C, the burner will fi re (hea-
ting position) at minimum power until the temperature reaches
33°C, the burner will go out and the pump will continue to run
for two minutes.
If the fl ow temperature remains between 4-8°C the pump will con-
tinue to run for two minutes for a maximum of 10 times unless a
temperature above 8°C is detected in the primary fl ow, after this
the the burner will fi re.
If lockout is caused by overheat the burner is kept OFF.
Note : In all cases, the circulation takes place in the central heating
system.
The anti-frost device activates only when (with the boiler opera-
ting correctly):
- the system pressure is correct;
- the boiler is electrically powered;
- there is a supply of gas.
Combustion Analysis
The fl ue connector has two apertures, readings can be taken
for the temperature of the combustion by-products and of the
combustion air, as well as of the concentrations of O2 and CO2,
etc.
To access these intakes it is necessary to unscrew the front screw
and remove the metal plate with sealing gasket.
It is possible to activate the fl ue test mode by pressing and holding
the
button for 10 seconds.
The boiler will return to normal operation after 10 minutes. The
boiler can be returned to normal operation sooner by switching
the boiler off and on again.
When you have fi nished, reposition the metal plate correctly and
make sure the seal fi ts perfectly.
Flue test mode
The P.C.B. enables the boiler to be forced to its maximum or
minimum power.
By activating the Flue test mode, (pressing the
button for
10 seconds), the boiler will be forced to its maximum heating
power and the display shows:
To select operation at maximum power, press the “+” button and
the following will appear on the display:
To select operation at minimum power, press the “-” button and
the following will appear on the display:
This function is de-activated automatically after 10 minutes, or
when the E
SC
button is pressed.
Note: The boiler can also be forced to its maximum and minimum
power by accessing menu 7 (see settings - adjustment - problem
identifi cation menu paragraph).
Product of Combustion
Discharge Monitoring
In the boiler, it is possible to monitor the correct operation of the
fl ue exhaust/air intake, checking for a loss of general pressure in the
system. Through the use of a diff erential manometer connected to
the test points of the combustion chamber, it is possible to detect
the ∆P of operation of the air pressure switch.
The value detected should not be less than 0.46 mbar (24/21 FF)
- 0.70 mbar (28/32 FF) under conditions of maximum thermal
power in order for the boiler to function properly and without
interruption.