REXNOVA ISA 20 BITHERMAL User manual

Wall-hung boiler with integrated heat exchanger
20kw Bithermal
ITALIAN DESIGN
MADE IN ITALY
INSTALLATION, COMMISSIONING, USE AND MAINTENANCE MANUAL
G20 ENGINEERING SRL Loc. Campogrande 13, 29013 CARPANETO PIACENTINO (PC), Italy
phone [phone] - fax. [phone] - www.aircontrol-pc.com - www.g20engineering.com
A Brand by G20 ENGINEERING
A brand by G20 ENGINEERING

1
ISA 20 KW BITHERMAL BOILER MANUAL
VERS. 07/2016 - REV.1

2
CONTENTS
GENERAL INFORMATION
General requirements 2
- General information 2
Use and operation 3
- Unit description 3
- Components 3
- Interface description 4
- Season selection menu 4
- Temperature setting menu 5
- Operating by room thermostat 6
- Special functions 6
- Faults 6
- Fault codes table 7
Installation 8
- Operational diagram 8
- Electrical wiring diagram 8
- Graphs for the head available to the system 9
- Installation 9
- Fastening the boiler to the wall 10
- Layout of connections 11
- Connection to hydraulic system 11
- Filling the system 12
- Connection to the mains gas supply 12
- Connection to the mains electrical system 13
- Combustion gas evacuation system: compatible
applications 14
- Combustion gas evacuation system: installation 15
- Checking the effectiveness of combustion gas
evacuation 16
- Combustion gas evacuation circuit diaphragms 16
- Air intake and combustion gas evacuation system:
warnings 17
Adjustment and maintenance 18
- Preliminary maintenance operations 18
- General maintenance operations 18
- Service function 18
- Power adjustment 20
- Gas pressure check 21
- Checking the pressure at the burner 21
- Checking mains gas supply dynamic pressure 22
- Checking pressure at burner at maximum power 23
- Changing gas type 23
- Conguring the software for a change in gas type
24
- Accessing the conguration menu 25
- Installer menu 26
- Room Thermostat installation 27
- Special functions 28
- Technical Data Sheet 29
GENERAL REQUIREMENTS
This manual, supplied with every boiler, should be considered
as an integral component as it contains instructions for the
correct, safe and appropriate installation, use and maintenance
of the system.
The manual must always be kept by the user of the boiler
and made available for the installation and/or maintenance
technicians to consult. It must also accompany the boiler if it
should be moved or otherwise transferred.
The manufacturer shall not be held responsible for any damage
caused by failure to follow the instructions contained in this
manual, nor:
If the boiler is used for purposes other than those for which it
was built
If any part or circuit of the boiler is modied
If accessories or kits not approved by the manufacturer are
installed
If ordinary and extraordinary maintenance is not performed
by qualied personnel
If applicable technical and legal requirements have not been
observed during installation and maintenance of the boiler
WARNING!
If the boiler should cease to function or not function correctly,
deactivate it immediately by turning it off and then shutting
off the gas supply. Do not attempt any repairs or direct work
on the boiler.
Only personnel with the necessary qualications and licenses
must perform maintenance on the boiler. Any repairs must be
performed using only original parts and accessories.
SYMBOLS USED IN THE MANUAL
Advice, suggestion, note
Important communications, signaling of modes
and operations which could compromise the
correct operation of the boiler and endanger
people.

3
DESCRIPTION OF THE BOILER
COMPONENTS
20kW BITHERMAL Isa wall hung boiler opens
the range of Isa boilers.
Assembled with care, by using high quality
components, showing a compact and
elegant look, having a simple and intuitive
interface board, 20kW BITHERMAL Isa boiler is
recommended when efciency and simplicity
are needed.
20kW BITHERMAL Isa
1) FUMES EXTRACTOR
2) SAFETY THERMOSTAT
3) BITHERMAL PRIMARY HEAT EXCHANGER
4) DHW PROBE
5) CH PROBE
6) COMBUSTION CHAMBER
7) BURNER
8) IGNITION/DETECTION MONOELECTRODE
9) EARTH ELECTRODE
10) PRESSURE GAUGE
11) CIRCULATOR UNIT
12) DHW PRIORITY VALVE
13) WATER PRESSURE SWITCH
14) SAFETY VALVE
15) GAS VALVE
16) EXPANSION TANK
17) COMBUSTION GAS PRESSURE SWITCH
18) FILLING COCK
Pict. 1
Pict. 2
USE AND OPERATION

4
INTERFACE DESCRIPTION
SEASON SELECTION
TURNING THE BOILER ON
Turn on the boiler’s electrical supply by the
switch, which must be installed on the power
supply line to the boiler. The LCD display (will
turn on immediately, showing all the available
symbols for 5 seconds, and the program
version installed in the microprocessor for
further 5 seconds; the unit goes into stand-by
and the display shows the word “OFF”.
By pushing the “E” button, the boiler goes
into “ON” mode; the display shows CH circuit
temperature and the “TAP” symbol, thus
indicating the summer mode (Pict. 4).
The boiler has now been started and ready
to operate.
The boiler has three operating modes,
which depend on the active functions,
in response to the external temperature
or the user requirements:
The SUMMER mode can be set,
during which all the CH functions
are deactivated and the domestic
hot water production mode only is
maintained: this mode is selected by
pushing “E” button and then the “TAP”
symbol (Pict.4) is displayed; when
the unit is in stand-by, the CH circuit
temperature is shown on the display
TURNING THE BOILER OFF
Pushing several times the “E” button until the
word “OFF” is displayed.
(Pict. 4): during an intake of DHW water,
the DHW temperature is shown together
with the flashing “TAP” symbol and
with the “FLAME” symbol of the ignited
burner.
The WINTER mode is activated by
pushing “E” button and then the “TAP”
and “RADIATOR” symbols (Pict.5) are
displayed. In this mode, the unit satises
both DHW requests, and CH requests.
When the unit is in stand-by, the CH
circuit temperature is shown on the
Pict. 3
Pict. 3.1
WARNING: In this mode the
boiler is inactive but its electricity
supply is still connected!
A
B E F D
C
A. DHW TEMPERATURE INCREASE
B. DHW TEMPERATURE DECREASE
C. CH TEMPERATURE INCREASE
D. CH TEMPERATURE DECREASE
E. FUNCTION SELECTION
F. RESET BUTTON

5
TEMPERATURE SETTING
It is possible to regulate the temperature of
the domestic hot water supplied as well as
that for the central heating. Once the desired
temperature is set, during the requests the set
temperature value is reached, if possible, and
maintained at the set value.
In order to set the supplied DHW temperature,
push “A” button to increase the value and
“B” button to decrease it; the display shows
the corresponding value and the ashing
symbol of DHW mode (“TAP”); the set value
and the mode symbol are displayed for 5
seconds, then the previous visualization mode
is restored and the value is memorized. The
minimum DHW temperature which can be set
is 35°C, the maximum one is 55°C.
In order to set the supplied CH temperature,
push “C” button to increase the value and
“D” button to decrease it; the display shows
the corresponding value and the ashing
symbol of CH mode (“RADIATOR”); the set
display; during an intake of DHW water,
the DHW temperature is shown together
with the flashing “TAP” symbol and
with the “FLAME” symbol of the ignited
burner; while in DHW mode, the display
shows the CH temperature value, the
“FLAME” symbol of the ignited burner
and the “RADIATOR” mode flashing
symbol (Pict.6).
value and the mode symbol are displayed
for 5 seconds, then the previous visualization
mode is restored and the value is memorized.
The range of temperature goes from 35 to
80°C.
ASK YOUR AREA INSTALLER FOR
INFORMATION ON THE TYPE
OF SYSTEM CONNECTED AND
RESPECTIVE ADJUSTMENTS
The HEAT ONLY mode is activated
by pushing “E” button and then the
“RADIATOR” symbol is displayed (Pict. 6).
In this mode, the unit will fulfill CH
requests only.
Pict. 4 Pict. 5 Pict. 6
SUMMER EXAMPLE HEAT ONLYWINTER EXAMPLE

6
OPERATING BY ROOM THERMOSTAT
In compliance with current standards in
terms of energy saving, the device must be
connected to a room thermostat for optimal
temperature adjustment and maintenance
in domestic environments.
ASK YOUR AREA INSTALLER FOR
INFORMATION ABOUT INSTALLATION
AND FUNCTIONING OF ROOM
THERMOSTAT
SPECIAL FUNCTIONS
FAULTS
CH Anti-Frost function
The anti-frost function is always active and
prevents the CH system water from freezing.
In the CH water temperature probe detects
a too low temperature, the circulator is
activated and the burner ignites at the
minimum power. The functions remains
active until a preset temperature (30°C)
is reached which prevents the CH system
water from freezing.
All functions supported by the boiler are
managed by a microprocessor-based system
which, aside from allowing the system to run
perfectly in order to maintain the greatest
level of comfort possible, constantly monitors
the functional parameters, ensuring they fall
within the necessary safety interval by a wide
margin, and therefore that all devices present
are functioning perfectly.
Whenever the malfunction of any component
or conditions which could compromise safe
operation of the system are detected, the
microprocessor system places the device into
a limited operation mode or even completely
prevents it from operating. The microprocessor
system is able to detect and issue warnings for
the main fault conditions to allow the system to
be brought back to normal conditions as soon
as possible. Fault warnings are given on the
LCD display. The malfunction is detected and
an intermittent warning displayed immediately,
consisting of a number preceded by the “E”
error symbol (Pict. 7). Faults are displayed on any
screen of the main menu.
Conditions causing transitory faults are possible.
Many of these are recognized and cause a
temporary block which is automatically reset
once the condition causing the fault has
stopped. Some of these provide for the possibility
to attempt to restore operation manually.
IF THE UNIT IS EXPECTED TO WORK IN VERY COLD ENVIRONMENTS, ALWAYS KEEP
THE SYSTEM POWERED ON WITH ALL THE SHUT-OFF VALVES BEING LEFT OPEN.
THIS FUNTION DOES NOT FULLY PROTECT THE UNIT AGAINST FREEZING, SINCE IT
DEPENDS ON CONTINUOUS POWER SUPPLY AND GAS SUPPLY.
ASK YOUR AREA INSTALLER FOR INFORMATION ABOUT CONFIGURING THE UNIT
INORDER TO PROTECT IT FROM VERY COLD TEMPERATURE.
Pict. 7

7
FAULT CODES TABLE
To manually reset the system following a fault
condition, press “F” button (Pict.3).
If the operation is successful the boiler will return
to normal operation; if not, the error code
causing the malfunction will be displayed and
technical support will be needed.
IF A FAULT IS NOT SOLVED AFTER
2 MANUAL RESET ATTEMPTS, THE
AUTHORISED AFTER SALES SERVICE
MUST BE CONTACTED.
Pict. 7
Code Possible cause Behaviour Possible actions
E01 Ignition failed Boiler locked
Ensure gas supply valves
before boiler are open
Reset the boiler
Consult technical support
E02 Air pressure switch failure Boiler locked Consult technical support
E03 Heating system temperature
sensor fault Boiler locked Consult technical support
E04 Domestic hot water system
temperature sensor fault
DHW supplied in provisional
mode
Heating functions normally
Consult technical support
E05 Gas regulation valve fault Operation at reduced
power Consult technical support
E08 Central heating system
pressure too low Boiler locked
Check for leaks in CH
system
Restore sufcient water
pressure to CH system
Consult technical support
E09 Central heating system
water temperature too high Boiler locked Reset the boiler Consult technical support
E13 Electronic board error
Boiler locked Consult technical support
E70
Low tension to electronic
board
Boiler locked Consult technical support
E71
Missing circulation in
CH circuit
Boiler locked
Possibile arresto del
circolatore
E99
Parameter conguration error
Boiler locked Check and recongure
the parameters

8
1
2
3
10
9
7
6
5
GAS
INTAKE
DOMESTIC
HOT WATER
WATER
INTAKE
CH
RETURN
CH FLOW
OPERATING DIAGRAM
ELECTRICAL WIRING DIAGRAM
INSTALLATION
1) Primary heat exchanger
2) Burner
3) Gas valve
5) Safety valve
6) Filling loop cock
7) Hot water priority turbine
9) Circulator unit
10) Expansion tank
Pict. 8
Pict. 9
GND
SIGN
+5VDC
FLUX
VG MODULATOR
D.H.W. PROBE
HEATING PROBE
SAFETY THERMOSTAT
LINE POWER
NEUTRAL POWER
EARTHING
BOILER
EARTHING
L
N
IGNITOR
EARTHING
OPEN THERM
ROOM THERMOSTAT
WATER PRESSURE SWITCH
AIR PRESS. SWITCH
NEUTRAL
FASE
GAS VALVE
FAN LINE
FAN NEUTRAL
CIRC.R NEUTRAL
CIRC. LINE
NEUTRAL
FASE

9
GRAPHS FOR THE HEAD AVAILABLE TO THE SYSTEM
INSTALLATION
Pict. 10
Use:
The boiler has been constructed according
to current technical standards and the most
stringent safety rules. Despite this, improper
use may endanger persons and property as
well as damaging the boiler itself.
This boiler has been designed as a thermal
generator for closed-loop central heating
systems and for the production of domestic
hot water.
This boiler is only for heating water to a
temperature below that of boiling point at
atmospheric temperature.
Any use different from those outlined herein is
to be considered improper. The manufacturer/
supplier declines any responsibility for damage
or injury caused by improper use.
Using the boiler according to its design also
means respecting the instructions given in
the operation and maintenance manuals
and observing the general inspection and
maintenance conditions.
General requirements
• The installation must be performed by
qualified and licensed personnel only.
They also assume responsibility for correct
installation, adjustment and commissioning.
Adjustment, maintenance and repair of the
boiler must be performed by qualied and
authorized personnel only.
• Do not install the boiler in environments
containing dust or strong vapors.
The presence of substances such as uorine,
chlorine, sulphur etc. (e.g. vapors from sprays,
solvents or detergents, paints, adhesives or
fuels) may cause the boiler’s components
or combustion gas evacuation system to
corrode and become damaged.
Avoid installing the boiler directly in
commercial/industrial premises (e.g. hair
salons, painting/carpentry workshops,
cleaning companies etc.).
• The boiler must be installed in ventilated
premises.
• Install the device respecting the minimum
distances and spaces in Pict. 11 (also when
installing inside an enclosure).
• Mount the boiler on a solid wall.
• Ensure that there are no depressions which
could cause the boiler to stand out from the
wall.
• Ensure you do not drill into tracked cables
or piping when drilling.
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
120 180 240 300 360 540 600 660 720 840 900 960 1080
5.5
6
420 480 780 1020 1140 12601200
Q L/h
Dp mCa
for 15-50 (Symona 20Kw)

10
Pict. 11
Pict. 12
FASTENING THE BOILER TO THE WALL
Attach the cardboard template giving the
connection and fastening schemes to the
wall, paying attention to the boiler dimensions
and necessary clearances. (Pict. 12)
• Use a suitable bit to drill the holes indicated
by the two wall plug symbols on the template.
• Remove the template; insert the two wall
plugs in the previously prepared holes, then
hang the boiler, inserting the hooks of the
plugs in the specic boiler holes.
Fasten the template so that its axis
coincides perfectly with that of the
boiler.
690
MURO / WALL
58 60
50
3/4" 1/2" 3/4"
MANDATA RISCALD.
C.H. OUTPUT
INGRESSO GAS
GAS INLET
ACQUA CALDA SANITARIA
D.H.W.
6065
97
1/2" 3/4"
140
RITORNO RISCALD.
C.H. INPUT
INGRESSO ACQUA SAN.
D.H.W. INLET
DIMA
TEMPLATE
18
390
200
109 15BT
53
18

11
Pict. 12
Pict. 13
LAYOUT OF CONNECTIONS
CONNECTION TO HYDRAULIC SYSTEM
Connect the water and central heating
pipes to the boiler, respecting the positions
and distances indicated (Pict. 12); take
particular care when connecting pipes to
ensure they are not placed under pressure
in order to minimise the danger of future
leaks. Use appropriate tools and procedures
for tightening.
Before connecting the pipes:
Clean the pipes and the radiators
thoroughly to make sure that any
impurities which may be there are
completely removed.
Connect the safety valve outlet
so that its operation will not
cause any damage to persons
or property.
• Use piping of not less than 1/2”
diameter
• Ensure that the line is always at
atmospheric pressure by using
suitable traps (do not connect
pipes directly to the valve outlet)
• Connect the safety valve outlet
line to the household grey water
drainage system
• Apply suitable protection to the
drainage line – the water carried
in it may be at high temperatures
• The manufacturer assumes no
responsibility for damage caused
to persons or property due to
operation of the safety valve
Do not use the plumbing pipework
connections as earth points for
electrical equipment

12
FILLING THE SYSTEM
CONNECTION TO THE MAINS GAS SUPPLY
Before connecting the boiler to the mains
gas, check that it is arranged for functioning
with the available type of gas. Thoroughly
ush all the gas pipes to remove any residues
which could compromise correct operation
of the boiler.
The gas supply must be connected to the
boiler intake (Pict. 15), following all applicable
regulations. Rigid metal piping or continuous-
wall stainless-steel hose must be used and a
shut-off valve must be connected before
the boiler.
Check that the ow rate from the line from
the gas meter is sufficient to support the
simultaneous use of all equipment connected
to it.
Check that there is no significant drop in
pressure along the distribution line from the
gas meter; pipes of sufcient diameter must
therefore be used to satisfy this requirement.
Perform the lling and topping
up of the system with the boiler
completely off and all parts at
room temperature.
Always close the filling loop
cock once you have nished the
operation.
Pict. 14
Pict. 15
When all of the boiler connections have been
plumbed in, it is possible to proceed to ll the
central heating circuit. Perform the operation
slowly to help all air bleeding out of the system.
When lling, check all the internal and external
parts of the system to make sure they are perfectly
tight.
• Open the bleed valves on the radiators
• Gradually open the lling loop cock (Pict. 14),
ensuring that any automatic air bleed valves
installed on the system are working correctly.
• Close the radiator bleed valves as soon as water
starts to come out
• Check on the boiler pressure gauge that a
pressure of between 1.3 and 1.6 bar has been
reached.
• Close the lling loop and then

13
Pict. 14
Pict. 15
CONNECTION TO THE MAINS ELECTRICAL SYSTEM
Check that all connections are
perfectly tight before opening
the boiler’s gas connection.
Check that all devices
necessary for creating
and limiting the maximum
permissible pressure of the
relative gas are installed
in the system before
opening the boiler’s gas
connection.
Another important feature to comply with
for achieving the full system’s safety is the
boiler’s correct connection to the mains
electrical supply in accordance with all
applicable regulations: in particular, the
boiler must be connected to a suitable
protective earthing system.
The device is fitted with a three-core
electrical cable supplied without a plug.
It must be connected to the mains with
a dedicated connection via dual-pole
switch whose contacts have an opening
of at least 3 mm. It is important to respect
the correct polarity (LIVE: brown cable
/ NEUTRAL: blue cable / EARTH: yellow-
green cable) when wiring in the boiler.
When installing or replacing the power-
supply cable, the earth conductor must
be left 2 cm longer than the others. If it
is necessary to completely replace the
pre-wired power-supply cable, the PCB
compartment will have to be accessed:
• Cut power to the boiler using the power
switch installed before it.
• Remove the lower cover by removing
the four screws; turn the instrument panel
to the open position.
• Remove the rear case cover by
unscrewing the 4 screws.
• Identify the terminals next to the PCB
(Pict. 16) and disconnect the live, neutral
and earth poles of the pre-wired cable;
remove the cable; connect the new cable
in the same position.
For the connections or the replacement of
conductors, use H05VV-F, H05VVH2-F CEI EN
60228 class cables or superior.
• Close the rear cover and screw it closed.
• Return the panel to its operational position
and reposition the lower protection.
Do not use the gas supply
pipework connections as earth
points for electrical equipment.
Always install a gas shut-off
valve before the device. This
must have a YELLOW valve
handle and must be placed
in a position which allows full
access to it.
Pict. 16
L
N

14
A qualified electrician should
check the suitability of the
protective earth system. The
manufacturer is not responsible
for any damage caused by
the lack of a suitable system
earth. Check that the electrical
connection is sufcient to satisfy
the boiler’s maximum power
consumption, indicated on the
boiler plate.
Extensions, adaptors or gang
sockets must not be used when
connecting the device to the
mains electrical system.
COMBUSTION GAS EVACUATION SYSTEM: COMPATIBLE APPLICATIONS
The boiler is a “C type”, sealed chamber, fan-
assisted device; the air intake and ue must be
connected to a combustion gas evacuation/ air
intake system. The types of permissible air intake
and combustion gas evacuation (ue) systems are
listed on the technical data plate and summarized
below:
• C12 concentric wall ue. The pipes may also be
split, but the outlets must be exposed to similar
wind conditions.
• C32 concentric vertical ue (with the same
specications as C12 type)
• C42 combustion gas evacuation and air intake
in separate common ues, but which are exposed
to similar wind conditions.
• C52 separate horizontal or vertical ues, in any
case in areas exposed to different pressures.
• C62 combustion gas evacuation and air intake
made with pipes which are sold and certied
separately.
C12
C42 C52
C32
95
230
min.
250
Pict. 17

15
Pict. 18
COMBUSTION GAS EVACUATION SYSTEM: INSTALLATION
The boiler, based on its UNI 7129 classication,
can be connected to COAXIAL intake and
ue evacuation systems.
The “coaxial” system is composed of a single
pipe containing both the ue and intake pipes
on the same axis. The system provides for all
The length of this system is limited by
its large pressure drops. The maximum
possible length therefore depends on
the components used to create the line
and can be determined by adding the
“Equivalent lengths” for each individual
component used (excluding the initial 90°
elbow) listed in the “COAXIAL SYSTEM”
table.
IT IS ESSENTIAL NOT TO EXCEED THE MAXIMUM
PERMISSIBLE LENGTH!
Consult the maximum length values
listed in the “FLUE SYSTEM TECHNICAL
CHARACTERISTICS” at page 16 for COAXIAL
systems relative to the type of device
installed.
The “split” ue system consists of one pipe
for combustion gas evacuation connected
to the fan outlet and one pipe for the air
intake connected to the hole on the roof
of the sealed chamber. The system provides
60/100 mm DIIAMETER COAXIAL SYSTEM
components necessary for completing the
line, including changes of direction, straight
sections of various lengths, connections to
the boiler and outside terminals as well as all
necessary seals. Below is a list of compatible
components with the relevant features:
for all components which are needed for
completing the line, including changes
of direction, straight sections of various
lengths, connections to the boiler and
outside terminals as well as all necessary
seals, for both pipes. Below is a list of
compatible components with their relative
characteristics.
No. Description Pressure drop (Pa) Equivalent length m
1 Terminal L.990 25 2.8
2 Extension L.1000 M-F 6 1
3Vertical anged coupling M 15 2.2
4 90° elbow M-F 7 1.3
5 45° elbow 6 1
6 d 128 Neoprene gasket d 128
7 d 100 Intake gasket d 100
8d 60 Flue evacuation gasket d 60

16
FLUE SYSTEMS TECHNICAL CHARACTERISTICS
CHECKING THE EFFECTIVENESS OF THE COMBUSTION GAS EVACUATION SYSTEM
COMBUSTION GAS EVACUATION CIRCUIT DIAPHRAGMS
Check the installation of the air/exhaust
system (for any possible ue system type) by
detecting the pressure of the fan exhaust
fumes (signal to the pressure switch) and using
a pressure switch differential of a suitable
range 0 - 500 Pa.
In order to be able to adapt the air intake
and combustion gas evacuation systems to
the various installation requirements while
keeping the functional characteristics of
the device unchanged, in compliance with
all applicable regulations regarding energy
output efficiency, it is necessary to fit a
diaphragm between the fan and ue duct for
systems of minimum or intermediate length.
The detected value shall not be less than
shown in the table “FLUE SYSTEMS TECHNICAL
CHARACTERISTICS“, column “SIGNAL” for the
exhaust system and for the examined power
and type of device.
The size of the diaphragm depends on the
type and length of the ducts which the boiler
must be connected to, or in other words the
pressure drop for the entire combustion gas
evacuation and air intake system.
The “DIAPHRAGMS” table below gives
the dimensions of the diaphragms to be
positioned at the fan outlet (Pict. 19) by type
of duct and boiler.
Model Heat output COAXIAL SYSTEM
Maximum Length Signal
20kW Bithermal Isa 20 kW 5 meters >138 Pascal
DIAPHRAGM
Pict. 19

17
DIAPHRAGM
COAXIAL SYSTEM Diaphragm diameter
FROM LENGTH TO LENGTH 20kW BITHERMAL Isa
0.5 meters 1 meter 37 mm
> 1 meter 2 meters 41 mm
> 2 meters 3 meters 41 mm
> 3 meters 4 meters 44 mm
> 4 meters 5 meters --
ALWAYS CONNECT A MINIMUM FLUE EVACUATION AND INTAKE SECTION FOR
BOTH SYSTEMS OF AT LEAST 0.5 METERS (COAXIAL PIPE L= 0.5m + 90° ELBOW PIPE)
FOLLOW APPLICABLE LEGISLATION AND REGULATIONS TO THE LETTER
INSTALL AIR INTAKE AND FLUE EVACUATION SYSTEMS CONFORMING TO THE
SPECIFICATIONS GIVEN ON THE TECHNICAL DATA PLATE AND OBSERVE ANY
LIMITATIONS ARISING FROM APPLICABLE LEGISLATION AND REGULATIONS TO THE
LETTER.
ONLY USE APPROVED COMPONENTS FOR AIR INTAKE AND COMBUSTION GAS
EVACUATION SYSTEMS WHICH ARE OF THE CORRECT DIMENSIONS AND PURPOSELY
DESIGNED AND MANUFACTURED FOR THE PURPOSE.
FOLLOW INSTALLATION INSTRUCTIONS TO THE LETTER.
INSULATE ANY FLUE SECTIONS WHICH WILL BE EXPOSED TO LOW TEMPERATURES.
TAKE MEASURES TO AVOID THE FORMATION OF EXCESSIVE CONDENSATION. ENSURE
THAT ANY CONDENSATION DOES NOT EVEN MINIMALLY AFFECT ANY INTERNAL
PART OF THE BOILER.
WHENEVER NECESSARY, PLACE APPROPRIATE CONDENSATE TRAPS ON THE FLUE
EVACUATION LINE:
BEFORE COMMISSIONING THE BOILER, MAKE SURE THAT:
• THE FLUE EVACUATION AND AIR INTAKE DUCTS ARE PERFECTLY SEALED
• THE FLUE EVACUATION AND AIR INTAKE DUCTS ARE CORRECTLY POSITIONED
AND FASTENED
•.THERE ARE NO MECHANICAL, THERMAL OR CHEMICAL STRESSES ON THE LINES
WHICH COULD EVEN MOMENTARILY COMPROMISE THEIR INTEGRITY.
INSTALL SYSTEMS TO ABSORB ANY THERMAL EXPANSION WHEN THE SECTIONS OF
FLUE DUCTING ARE LONGER THAN THE MINIMUM SPECIFIED LENGTHS.
AIR INTAKE AND COMBUSTION GAS EVACUATION SYSTEM: WARNINGS

18
If any components of the boiler require replacement, original spare parts supplied by
the manufacturer must be used. Use of other components could compromise correct
operation of the device. The manufacturer declines any responsibility for consequences
linked to the use of non-original spare parts.
At the end of the maintenance procedure a report must be prepared and left with the
owner. This must contain the ndings of the inspection, any work performed and any
recommendations.
ADJUSTMENT AND MAINTENANCE
All maintenance operations MUST BE
PERFORMED BY QUALIFIED PERSONNEL.
These operations must also be performed in full
compliance with all applicable legislation and
regulations. The boiler should be inspected by
a qualied technician at the end of every
heating season (winter) and whenever else
it is considered necessary in order to keep it
in perfect operating conditions.
PRELIMINARY MAINTENANCE OPERATIONS
GENERAL MAINTENANCE OPERATIONS
SERVICE FUNCTION
•Declaration of conformity check.
•Boiler logbook check.
•Check that the Instruction Manual is present
•Visual check of the installation (in conformity
with applicable regulations).
•Clean any deposits on the heat exchangers
and electrodes
• Remove any oxidation on the burner
•Check that the boiler ignites, turns off and
functions correctly
•Visual check for leaks in gas and water pipes
and unions
•Check that the safety devices are operational
•Check that the boiler’s control and regulation
This function allows the boiler to be run at
minimum and maximum power conditions
during maintenance and adjustment
operations, independently of the room
thermostat signals. The boiler installation
must be completed before activating the
“SERVICE” function. Before activating this
function check that all conditions specied
in the “Commissioning” chapter have been
satised.
•Visual check of the ue system.
•Check that combustion gases are being
properly evacuated.
devices are functioning correctly
•Check that the combustion gas evacuation
device and/or duct is in good condition and
operating correctly
•Perform a visual check that the safety valve
outlet is not blocked
•Check hydraulic system static pressure
Activating the function:
In order to activate “SERVICE” function, press
at the same time “F” button and “C” button
for 3 seconds at least (Pict.20).
After entering “SERVICE” mode, “C-5” and the
CH temperature are displayed alternatively.
While in “SERVICE” mode, the diverting valve
prepares the unit to function in heating mode.