Ariston CLAS B 28 FF, Installation And Service Instructions Manual

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46
b oi l er protection de v ices
C om b ustion A na l ysis
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.
P roduct o f C om b ustion
Discharge M onitoring
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 ΔP of operation of the air pressure switch.
The value detected should not be less than 0.47 mbar (24 kW) - 0.70
mbar (28/35 kW) under conditions of maximum thermal power in
order for the boiler to function properly and without interruption.
A nti -f rost De v ice .
The anti-frost function acts on the central heating fl ow temperature pro-
be, independently from other regulations, when the electrical 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 central heating fl ow temperature is between 4 and 8°C, the
pump will run for another two minutes;
c) if the central heating fl ow temperature is < 4°C, the burner will fi re
(heating position) at minimum power until the temperature rea-
ches 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 central heating fl ow, after
this the the burner will fi re. If lockout is caused by overheat the bur-
ner is kept OFF.
The anti-frost device activates only when (with the boiler operating
correctly):
- the system pressure is correct;
- the boiler is electrically powered;
- there is a supply of gas.
C himney s w eep f unction
The P.C.B. enables the boiler to be forced to its maximum or
minimum power.
By activating the Chimney sweep function, pressing the Reset
button for 10 seconds, the boiler will be forced to its maximum
heating power and the display shows:
To select hot water operation at maximum power, press the
button and the following will appear on the display:
To select hot water operation at minimum power, press the
button and the following will appear on the display:
This function is deactivated automatically after 10 minutes, or
when the RESET button is pressed.
N ote : The boiler can also be forced to its maximum and minimum
power by accessing menu 7 (see settings - adjustment - problem
identifi cation menu paragraph).