5 MAINTENANCE AND CLEANING
Periodic maintenance is an "obligation" required by the law and is es-
sential to the safety, efficiency and duration of the boiler. It allows for the
reduction of consumption, polluting emissions and keeping the product
safe and reliable over time. Before starting maintenance operations:
close the fuel and water taps of the heating and domestic hot water
system.
To ensure product characteristics and efficiency remain intact and to
comply with prescriptions of current regulations, it is necessary to render
the appliance to systematic checks at regular intervals. When carrying
out maintenance work, respect the indications given in chapter "1 WAR-
NINGS AND SAFETY
This normally means the following tasks:
removing any oxidation from the burner
removing any encrustation from the heat exchangers
check the state of deterioration of the electrode and, if it is deteriora-
ted, replace it together with the relative seal
check and general cleaning of the exhaust and intake pipes
checking the external appearance of the boiler
checking the ignition, switch-off and operation of the appliance, in
both DHW and heating mode
checking the seal on the couplings and on the gas, water and conden-
sate connection pipes
checking the gas consumption at maximum and minimum output
if the DHW pressure is lower than 3 bar, drain the boiler DHW circuit
and check the heating circuit pressure is maintained
check the condition of the insulation on the electric cables, especially
near the primary heat exchanger
checking the gas failure safety device
check that the water is present in the siphon, otherwise fill it.
b
During boiler maintenance, the use of protective clothing is
recommended to avoid any risk of personal injury.
b
After carrying out the maintenance tasks, an analysis of the
combustion products is needed to make sure the boiler is working
correctly.
b
In the event that, after any replacement of the electronic board,
exchanger, fan/mixer, gas valve, or having carried out maintenance
on the detection electrode or on the burner, the analysis of the
combustion products returns values that are out of tolerance, it
is necessary to repeat the procedure described in paragraph "4.8
Combustion analysis".
b
Do not clean the appliance or its parts with inflammable substances
(e.g. petrol, alcohol, etc.).
b
Do not clean panels, painted parts and plastic parts with paint
thinner.
b
Panel cleaning must be carried out only with soapy water.
Cleaning the primary heat exchanger
Switch off the electrical supply by turning the system's main switch
to "Off".
Close the gas shut-off valve.
Remove the casing as explained in paragraph "3.7 Removing the ca-
sing".
Disconnect the connecting cable of the electrode.
Disconnect the power cables of the fan.
Take out the clip of the fixing ramp (A) from the mixer.
Loosen the nut of the gas train (B).
Rotate and take out the gas ramp from the mixer.
Remove the 4 nuts (C) that fix the combustion unit.
Take out the air/gas conveyor assembly including the fan and mixer,
being careful not to damage the insulating panel and the electrode.
Remove the siphon connecting pipe from the condensate drain fitting
of the heat exchanger and connect a temporary collecting pipe. At this
point proceed with the heat exchanger cleaning operations.
Vacuum out any dirt residue inside the heat exchanger, being careful
NOT to damage the retarder insulating panel.
Clean the coils of the heat exchanger with a soft bristled brush.
b
DO NOT USE METAL BRUSHES THAT COULD DAMAGE THE
COMPONENTS.
Clean the spaces between the coils using a 0.4 mm thick blade (also
available in a kit).
Vacuum away any residue produced by the cleaning.
Rinse with water, being careful NOT to damage the retarder insulation
panel.
b
In case of stubborn deposits of combustion products on the
surface of the exchanger, clean by spraying natural white vinegar,
taking care NOT to damage the retarder insulation panel.
Leave for a few minutes.
Clean the coils of the exchanger with a soft bristle brush.
b
DO NOT USE METALLIC BRUSHES WHICH CAN DAMAGE THE
COMPONENTS.
Rinse with water, taking care NOT to damage the retarder insulation
panel.
".
Make sure the retarder insulation panel is undamaged and replace it
if necessary following the relative procedure.
Once the cleaning operations are finished, carefully reassemble all
the components, following the above instructions in the reverse order.
To close the fixing nuts of the air/gas conveyor assembly, use a tighte-
ning torque of 6 Nm following the sequence indicated on the diecast
(1,2,3,4).
Turn the power and gas feeding to the boiler back on.
Cleaning the burner:
Switch off the electrical supply by turning the system's main switch
to "Off".
Close the gas shut-off valve.
Remove the casing as explained in paragraph "3.7 Removing the casing".
Disconnect the connecting cable of the electrode.
Disconnect the power cables of the fan.
Take out the clip of the fixing ramp (A) from the mixer.
LOosen the nut of the gas train (B).
Rotate and take out the gas ramp from the mixer.
Remove the 4 nuts (C) that fix the combustion unit.
Take out the air/gas conveyor assembly including the fan and mixer,
being careful not to damage the ceramic insulation panel and the
electrode. At this point proceed with the burner cleaning operations.
Clean the burner with a soft bristled brush, being careful not to dama-
ge the insulation panel and the electrode.
b
DO NOT USE METAL BRUSHES THAT COULD DAMAGE THE
COMPONENTS.
Check that the burner insulating panel and the sealing gasket are
undamaged and replace them if necessary, following the relative pro-
cedure.
Once the cleaning operations are finished, carefully reassemble all
the components, following the above instructions in the reverse order.
To close the fixing nuts of the air/gas conveyor assembly, use a tighte-
ning torque of 6 Nm.
Turn the power and gas feeding to the boiler back on.
Replacing the burner insulating panel
Unscrew the ignition/detection electrode fixing screws and remove it.
Remove the burner insulating panel (D) by inserting a blade
underneath the surface (as shown in the figure).
Remove any fixing glue residue.
Replace the insulating panel.
The new insulating panel does not need to be fixed in place with glue
as its geometry ensures perfect coupling with the heat exchanger
flange.
Reassemble the ignition/detection electrode using the previously
removed screws and replacing the relative seal.
B
Cleaning the siphon
Disconnect the tubes (A) and (B), remove the clip (C) and remove the
siphon.
Unscrew the bottom and the top caps, then remove the float.
Clean the parts of the siphon from any solid residues.
b
Do not remove the float and its sealing gasket as their presence
is intended to prevent the escape of burnt gases into the environ-
ment in the event of no condensation.
b
Once the operations have been completed, reassemble the com-
ponents by operating in the reverse order to what is described,
checking the floating seal and replace it if necessary. If replacing
the float gasket, make sure it is correctly positioned in its seat (see
figure in section).
b
At the end of the cleaning sequence, fill the siphon with water (see
"4.2 First commissioning") before restarting the boiler.
31
D
C
A
EN