87
NAKED FLAMES.
–Do not use calcium chloride to treat the
plastic component during generator
maintenance.
4.7.1
Chimney sweep function
(fig. 24)
To carry out the verification of combustion
in the boiler turn the selector and stop on
the position ( ) until the green/orange led
starts to flash intermittently.
From that moment the boiler will start func-
tioning in heating mode at the maximum
power, with switching off at 80°C and
restarting at 70°C.
Before activating the chimney sweep func-
tion make sure that the radiator valves or
eventual zone valves are open.
The test may be carried out also during hot-
water service functioning.
To do so it is enough, after having activated
the chimney sweep function, to take some
hot water from one or more cocks.
Even in this condition the boiler functions
at the maximum temperature always
with the primary controlled between
80°C and 70°C.
During the entire duration of the testing the
hot water taps must remain open.
After verifying the combustion the boiler
should be switched off by placing the selec-
tor on the
OFF
position; then return the
selector to the desired function.
ATTENTION:
After about 15 minutes, or once the hot
water request has been fulfilled, the
chimney sweep function automatically
deactivates.
4.8
FAULT FINDING
The burner does not ignite and the circu-
lator is working.
–Check that the water pressure reads
1 - 1.2 bar.
–The flowmeter is faulty, replace it.
Main burner does not start either to draw
off D.H.W. or for heating.
–Check flowmeter; if necessary, replace it.
–The smoke stat has tripped; reset it
(
“OF”
vers.).
–Check whether electric power is rea-
ching the gas valve actuator; check its
operation and, if necessary, replace it.
–Check operation of the smoke pressure
switch (
“BF”
vers.).
–The fan is operating but at low rpm, so
failing to activate the smoke pressure
switch (
“BF”
vers.); replace the fan.
–Replace the electronic card.
Boiler turns on, but after 10 seconds
“locks out”.
–Check that during electric wiring the
position of line and neutral have not been
inverted.
–The ignition/sensing electrode is faulty;
replace it.
–The control box is faulty; replace it.
Gas valve fails to modulate in D.H.W. and
C.H. modes.
–The sensor is interrupted; replace it.
–The modulator has a break in winding;
replace it.
–Check that the current to the modulator
complies with the specifications
–The control box is faulty; replace it.
Boiler is noisy or heat exchanger makes a
sizzling sound.
–Check whether circulation pump P is
obstructed; if necessary clear it out.
–Unclog impeller of circulation pump, clea-
ring away any impurities or sediments.
–Circulation pump is burnt out or has a
lower rpm than required; replace it.
–Check boiler output is adequate for
actual needs of heating system.
Boiler safety valve keeps tripping.
–Check charge cock is closed. If it doesn’t
close properly, replace it.
–Check system cold charge pressure is not
too high; keep to recommended values.
–Check whether safety valve is out of cali-
bration; if necessary, replace it.
–Check whether the vessel is sufficiently
capacious to contain the water for the
system.
–Check preloading pressure of expansion
vessel.
–Replace expansion vessel if faulty.
Radiators fail to heat up in winter.
–The rotary switch is on “Summer”; swit-
ch to “Winter”.
–The room stat is set too low or needs
replacing because faulty.
–The electrical connections of the room
stat are wrong.
Main burner burns badly: flames too high,
deep yellow.
–Check that pressure of burner gas is
regular.
–Check burners are clean.
–Check coaxial assembly has been instal-
led correctly (
“BF”
vers.).
Smell of unburnt gases.
–Check boiler is properly clean.
–Check draught is sufficient.
–Check gas consumption is not too high.
Boiler operates but does not increase temp.
–Check gas consumption is not lower
than it should be.
–Check boiler is clean.
–Check boiler is sized in proportion to
system.
In the “BF” boilers, upon demand for
D.H.W. or heating, fan fails to turn at
max speed.
–Make sure that the smoke pressure
switch is working and that the relative
contact is in the rest position.
–Check whether connection tubes of
smoke pressure switch are obstructed
and, if necessary, clean away impurities
or condensate.
–The smoke pressure switch needs repla-
cing.
–Replace electronic board.
Fig. 24
Spia lampeggiante
verde/arancio
FLASHING
GREEN/ORANGE LED
