Immergas MINI NIKE 24 3 E User manual

MINI NIKE
24 3 E
Instruction booklet and
warning
IE
*1.038790ENG*

Dear Customer,
Our compliments for having chosen a top-quality Immergas product, able to assure well-being and safety for a long period of time. As an Immergas customer
you can also count on a qualied aer-sales service, prepared and updated to guarantee constant eciency of your boiler. Read the following pages carefully: you
will be able to draw useful suggestions regarding the correct use of the appliance, the respect of which, will conrm your satisfaction for the Immergas product.
For any interventions or routine maintenance contact Authorised Centres: these have original spare parts and boast of specic preparation directly from the
manufacturer.
General recommendations
All Immergas products are protected with suitable transport packaging.
e material must be stored in dry environments protected against bad weather.
e instruction book is an integral and essential part of the product and must be consigned to the new user also in the case of transfer or succession of ownership.
It must be stored with care and consulted carefully, as all of the warnings provide important safety indications for installation, use and maintenance stages.
is instruction manual provides technical information for installing the Immergas kit. As for the other issues related to boiler installation (e.g. safety in the
work site, environment protection, injury prevention), it is necessary to comply with the provisions specied in the current regulation and technical standards.
In compliance with legislation in force, the systems must be designed by qualied professionals, within the dimensional limits established by the Law. Installation
and maintenance must be performed in compliance with the regulations in force, according to the manufacturer’s instructions and by an authorised company,
which has specic technical expertise in the system sector, as required by Law.
Improper installation or assembly of the Immergas appliance and/or components, accessories, kit and devices can cause unexpected problem to persons, animals
and objects. Read the instructions provided with the product carefully to ensure a proper installation.
Maintenance must be carried out by an authorised company. e Authorised Aer-sales Service represents a guarantee of qualication and professionalism.
e appliance must only be destined for the use for which it has been expressly declared. Any other use will be considered improper and therefore potentially
dangerous.
If errors occur during installation, operation and maintenance, due to non compliance with technical laws in force, standards or instructions contained in this
book (or however supplied by the manufacturer), the manufacturer is excluded from any contractual and extra-contractual liability for any damages and the
appliance warranty is invalidated.
e manufacturer declines all liability due to printing or transcription errors, reserving the right to make any modications to its technical and commercial
documents without forewarning.
Product not intended for EU countries

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INSTALLATORUSER
MAINTENANCE TECHNICIAN
INDEX
USER pageINSTALLATOR page MAINTENANCE TECHNICIAN page
1 Boiler installation......................................4
1.1 Installation recommendations.................4
1.2 Main dimensions.......................................4
1.3 Gas connection
(appliance category II2h3+). ......................5
1.4 Hydraulic connection...............................5
1.5 Electrical connection................................5
1.6 Remote controls and room
chronothermostats (optional). ................5
1.7 External probe (optional).........................5
1.8 Ventilation of the rooms. .........................6
1.9 Flue ducts. ..................................................6
1.10 Flues/chimneys..........................................6
1.11 System lling..............................................7
1.12 Gas system start-up...................................7
1.13 Boiler start up (ignition)................................7
1.14 Circulation pump......................................7
1.15 Kits available on request...........................7
1.16 Boiler components....................................8
2 Instructions for use and maintenance....9
2.1 Cleaning and maintenance. .....................9
2.2 Ventilation of the rooms...........................9
2.3 General warnings......................................9
2.4 Control panel.............................................9
2.5 Using the boiler........................................10
2.6 Troubleshooting. .....................................10
2.7 Boiler shutdown. .....................................12
2.8 Restore central heating system
pressure.....................................................12
2.9 System draining.......................................12
2.10 Anti-freeze protection. ...........................12
2.11 Case cleaning...........................................12
2.12 Decommissioning. ..................................12
3 Boiler start-up (initial check). ...............13
3.1 Hydraulic diagram. .................................13
3.2 Wiring diagram.......................................14
3.3 Troubleshooting. .....................................14
3.4 Information menu...................................15
3.5 Programming the p.C.B. ........................15
3.6 Converting the boiler to other types
of gas. ........................................................16
3.7 Checks following conversion to
another type of gas..................................16
3.8 Possible adjustments...............................17
3.9 Automatic slow ignition function
with timed ramp delivery.......................17
3.10 Chimney sweep” function......................17
3.11 Pump anti-block function......................17
3.12 ree-way anti-block function..............17
3.13 Radiators anti-freeze function...............17
3.14 P.C.B. Periodical self-check....................17
3.15 Solar panels coupling function..............17
3.16 Casing removal........................................18
3.17 Yearly appliance check and
maintenance.............................................20
3.18 Variable heat output................................20
3.19 Combustion parameters.........................21
3.20 Technical data..........................................21
3.21 Data plate key............................................22

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YES NO
1BOILER INSTALLATION
1.1 INSTALLATION
RECOMMENDATIONS.
e Mini Nike 24 3 E boiler has been designed
for wall mounted installation only, for central
heating and production of domestic hot water
for domestic use and similar purposes.
e place of installation of the appliance and
relative Immergas accessories must have suitable
features (technical and structural) such to allow
(always in safety, efficiency and comfortable
conditions):
- installation (according to the provisions of the
technical legislation and technical regulations);
- maintenance operations (including scheduled,
periodic, routine and special maintenance);
- removal (to outdoors in the place for
loading and transporting the appliances
and components) as well as their eventual
replacement with appliances and/or equivalent
components.
e wall surface must be smooth, without any
protrusions or recesses enabling access to the
rear part. ey are not designed to be installed
on plinths or oors (Fig. 1-1).
Only professionally enabled companies are
authorised to install Immergas gas appliances.
Installation must be carried out according to
regulation standards, current legislation and in
compliance with local technical regulations and
the required technical procedures.
Attention: the manufacturer declines all liability
for damages caused by boilers removed from
other systems or for any non-conformities of
such equipment.
Before installing the appliance, ensure that it
is delivered in perfect condition; if in doubt,
contact the supplier immediately. Packing
materials (staples, nails, plastic bags, polystyrene
foam, etc.) constitute a hazard and must be kept
out of the reach of children. If the appliance
is installed inside or between cabinets, ensure
sucient space for normal servicing; therefore
it is advisable to leave clearance of at least 3
cm between the boiler casing and the vertical
sides of the cabinet. Leave adequate space above
the boiler for possible water and ue removal
connections. It is just as important that the intake
grids are not obstructed. Keep all ammable
objects away from the appliance (paper, rags,
plastic, polystyrene, etc.). Do not place household
appliances underneath the boiler as they could
be damaged if the safety valve intervenes with
an obstructed conveying system (the safety valve
must be conveyed away by a draining funnel), or
if there are leaks from the hydraulic connections;
on the contrary, the manufacturer cannot be
held responsible for any damage caused to the
household appliances.
For the aforementioned reasons, we recommend
not placing furnishings, furniture, etc. under
the boiler.
In the event of malfunctions, faults or incorrect
operation, turn the appliance o immediately
and contact an authorised company (e.g.
the Technical Assistance centre, which has
specifically trained staff and original spare
parts). Do not attempt to modify or repair the
appliance alone. Failure to comply with the above
implies personal responsibility and invalidates
the warranty.
• Installation regulations:
- these boilers cannot be installed in bedrooms,
studio ats and bathrooms. ey also cannot
be installed in rooms with wood (or solid
fuel) burning heat generators and in adjacent
and communicating rooms;
- installation in places with a fire risk is
prohibited (for example: garages, closed
parking stalls), gas appliances and relative ue
ducts, ue exhaust pipes and combustion air
intake pipes;
- installation is prohibited on the vertical
projection of cooking hobs;
- installation is also prohibited in places/
environments that constitute common parts
of oce condominiums such as stairs, cellars,
entrance halls, attics, los, escape routes,
etc. if they are not located inside technical
compartments under the responsibility of
each individual building and only accessible
to the user (for the features of the technical
compartments, see the technical standards in
force);
- type B open chamber boilers must not be
installed in places where commercial, artisan
or industrial activities take place, which use
products that may develop volatile vapours
or substances (e.g. acid vapours, glues, paints,
solvents, combustibles, etc.), as well as dusts
(e.g. dust deriving from the working of
wood, coal nes, cement, etc.), which may be
harmful for the components of the appliance
and jeopardise operation;
- they must also be installed in rooms where
the temperature cannot fall below 0°C and
must not be exposed to weathering.
Attention: wall mounting of the boiler must
guarantee stable and ecient support for the
generator.
e plugs (standard supply) are to be used only in
conjunction with the mounting brackets or xing
template to x the appliance to the wall; they only
1.2 MAIN DIMENSIONS.
Key:
G - Gas supply
AC - Domestic hot water outlet
ACV - Solar valve kit DHW inlet
(Optional)
AF - Domestic cold water inlet
R - System return
M - System ow
V - Electrical connection
N.B.: connection group (optional)
Height
(mm)
Width
(mm)
Depth
(mm)
785 440 240
CONNECTIONS
GAS DOMESTIC
HOT WATER SYSTEM
GAC AF R M
3/4” 1/2” 1/2” 3/4” 3/4”

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INSTALLATORUSER
MAINTENANCE TECHNICIAN
ensure adequate support if inserted correctly
(according to technical standards) in walls made
of solid or semi-hollow brick or block. In the
case of walls made from hollow brick or block,
partitions with limited static properties, or in any
case walls other than those indicated, a static test
must be carried out to ensure adequate support.
N.B.: the hex head screws supplied in the blister
pack are to be used exclusively to x the relative
mounting bracket to the wall.
ese boilers are used to heat water to below
boiling temperature in atmospheric pressure.
ey must be connected to a central heating
system and hot water circuit suited to their
performance and capacity.
They cannot be connected directly to low-
temperature systems.
1.3 GAS CONNECTION.
Our boilers are designed to operate with methane
gas (G20) and LPG. Supply pipes must be the
same as or larger than the 3/4”G boiler tting.
Before connecting the gas line, carefully clean
inside all the fuel feed system pipes to remove any
residue that could impair boiler eciency. Also
make sure the gas corresponds to that for which
the boiler is prepared (see boiler data-plate). If
dierent, the appliance must be converted for op-
eration with the other type of gas (see converting
appliance for other gas types). e dynamic gas
supply (methane or LPG) pressure must also be
checked according to the type used in the boiler,
as insucient levels can reduce generator output
and cause malfunctions.
Ensure correct gas cock connection by follow-
ing the mounting instructions illustrated in
the gure. e gas supply pipe must be suitably
dimensioned according to current regulations in
order to guarantee correct gas ow to the burner
even in conditions of maximum generator output
and to guarantee appliance eciency (technical
specications). e coupling system must con-
form to standards.
Fuel gas quality. e appliance has been de-
signed to operate with gas free of impurities; oth-
erwise it is advisable to t special lters upstream
from the appliance to restore the purity of the gas.
Storage tanks (in case of supply from LPG
depot).
- New LPG storage tanks may contain residual
inert gases (nitrogen) that degrade the mixture
delivered to the appliance casing functioning
anomalies.
- Due to the composition of the LPG mixture,
layering of the mixture components may occur
during the period of storage in the tanks. is
can cause a variation in the heating power of
the mixture delivered to the appliance, with
subsequent change in its performance.
1.4 HYDRAULIC CONNECTION.
Important: In order not to void the warranty
before making the boiler connections, carefully
clean the heating system on the primary heat
exchanger (pipes, radiators, etc.) with special
pickling or de-scaling products to remove any
deposits that could compromise correct boiler
operation.
In compliance with Standards in force it is man-
datory to treat the water in the heating system
chemically in order to protect the system and
appliance from deposits of lime scale.
Hydraulic connections must be made in a
rational way using the couplings on the boiler
template. e boiler safety valve outlet must be
connected to an appropriate drain. Otherwise,
the manufacturer declines any responsibility in
case of ooding if the drain valve cuts in.
Attention: the manufacturer declines all liability
in the event of damage caused by the installation
of an automatic lling system.
Important: to preserve the duration of appliance
eciency features, in the presence of water whose
features can lead to the deposit of lime scale,
installation of the “polyphosphate dispenser” kit
is recommended.
1.5 ELECTRICAL CONNECTION.
e Mini Nike 24 3 E boiler has an IPX4D pro-
tection rating for the entire appliance. Electrical
safety of the unit is reached when it is cor-
rectly connected to an ecient earthing system
as specied by current safety standards.
Important: the manufacturer declines any
responsibility for damage or physical injury
caused by failure to connect the boiler to an
ecient earth system or failure to comply with
the reference standards.
Also ensure that the electrical installation cor-
responds to maximum absorbed power specica-
tions as shown on the boiler data-plate. Boilers
are supplied complete with an “X” type power
cable without plug. e power supply cable must
be connected to a 230V ±10% / 50Hz mains sup-
ply respecting L-N polarity and earth connection
. is network must also have an omnipolar
circuit breaker with class III over-voltage cat-
egory. When replacing the power supply cable,
contact a qualified firm (e.g. the Authorised
Aer-Sales Technical Assistance Service). e
power cable must be laid as shown. In the event
of mains fuse replacement on the P.C.B., use a
2A quick-blow fuse. For the main power supply
to the appliance, never use adapters, multiple
sockets or extension leads.
1.6 REMOTE CONTROLS AND
ROOM CHRONOTHERMOSTATS
OPTIONAL.
e boiler is prepared for the application of room
chronothermostats or remote controls, which are
available as optional kits. (Fig. 1-3)
All Immergas chronothermostats can be con-
nected with 2 wires only. Carefully read the
user and assembly instructions contained in the
accessory kit.
• On/O Immergas digital chrono-thermostat.
e chronothermostat allows:
- to set two room temperature values: one for
day (comfort temperature) and one for night
(lower temperature);
- set a weekly programme with four daily
switch on and switch o times;
- to select the required operating mode from
the various possible alternatives:
- manual mode (with adjustable temperature).
- automatic mode (with set programme).
- forced automatic mode (momentarily
changing the temperature of the automatic
programme).
e chronothermostat is powered by two 1.5V
LR 6 type alkaline batteries.
• Comando Amico Remoto, Remote Control De-
viceV2 (CARV2) with climate chronothermostat
function. In addition to the functions described
in the previous point, the CAR panelV2 enables
the user to control all the important informa-
tion regarding operation of the appliance and
the heating system with the opportunity of eas-
ily intervening on the previously set parameters
without having to go to the place where the ap-
pliance is installed. e panel is provided with
self-diagnosis to display any boiler functioning
anomalies. e climate chronothermostat in-
corporated into the remote panel enables the
system ow temperature to be adjusted to the
actual needs of the room being heated, in order
to obtain the desired room temperature with
extreme precision and therefore with evident
saving in running costs. e CARV2 is powered
directly by the boiler by means of the same 2
wires used for transmitting data between boiler
and device.
Important: If the system is subdivided into zones
using the relevant kit. the CARV2 must be used
with its climate thermostat function disabled, i.e.
it must be set to On/O mode.
Comando Amico Remoto remote controlV2
or On/O chronothermostat electrical con-
nections (Optional). e operations described
below must be performed aer having removed
the voltage from the appliance. Any thermostat
or On/O environment chronothermostat must
be connected to clamps 40 and 41 eliminating
jumper X40 (Fig. 3-2). Make sure that the On/
O thermostat contact is of the “clean” type, i.e.
independent of the mains supply, otherwise the
electronic adjustment card would be damaged.
Any Comando Amico Remoto remote controlV2
must be connected to clamps 40 and 41 elimi-
nating jumper X40 on the circuit board, paying
attention not to invert the connections (Fig. 3-2).
Important: if the Comando Amico Remoto
remote controlV2 or any other On/O chrono-
thermostat is used arrange two separate lines in
compliance with current regulations regarding
electrical systems. No boiler pipes must ever be
used to earth the electric system or telephone
lines. Ensure elimination of this risk before mak-
ing the boiler electrical connections.
1.7 EXTERNAL PROBE OPTIONAL.
e boiler is prepared for the application of the
external probe (Fig. 1-4), which is available as
an optional kit.
e probe can be connected directly to the boiler
electrical system and allows the max. system
ow temperature to be automatically decreased
when the external temperature increases, in
order to adjust the heat supplied to the system
according to the change in external temperature.
e external probe always acts when connected
independently from the presence or type of room
thermostat used. e correlation between system
On/O digital chronothermostat
Comando Amico Remoto remote controlV2 (CARV2)

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INSTALLATORUSER
MAINTENANCE TECHNICIAN
Position of the central
heating temperature user adjustment
ow temperature and external temperature is de-
termined by the position of the selector switch on
the boiler control panel according to the curves
shown in the diagram (Fig. 1-5). e electric con-
nection of the external probe must be made on
clamps 38 and 39 on the boiler P.C.B. (Fig. 3-2).
1.8 VENTILATION OF THE ROOMS.
In the room in which the boiler is installed it is
necessary that at least as much air ows as that
requested for by normal combustion of the gas
and ventilation of the room. Natural air ow must
take place directly through:
- permanent openings in the walls of the room
to ventilate that lead towards the outside;
- ventilation conduits, individual or collective
branched.
e air used for ventilation must be withdrawn
directly from outside, in an area away from sourc-
es of pollution. Natural air ow is also allowed
indirectly by air intake from adjoining rooms. For
further information relative to ventilation of the
rooms follow that envisioned in the regulation.
Evacuation of foul air. In the rooms where the
gas appliances are installed it may also be neces-
sary, as well as the intake of combustion agent air,
to evacuate foul air, with consequent intake of a
further equal amount of clean air. is must be
realised respecting the provisions of the technical
regulations in force.
1.9 FLUE DUCTS.
e gas appliances with attachment for the ues
discharge pipe must have direct connection to
chimneys or safely ecient ues.
Only if these are missing can the combustion
products be discharged directly to the outside,
as long as the standard regulations for the ue
terminal are respected as well as the existing laws.
Connection to chimneys or ues. e connec-
tion of the appliances to a chimney or ue takes
place by means of ue ducts.
In the case of connection to pre-existing ues, these
must be perfectly clean as the slag, if present, on
detachment from the walls during functioning,
could obstruct the passage of ue gass, causing
extremely dangerous situations for the user.
e ue ducts must be connected to the chimney
or ue in the same room in which the appliance
is installed or, at most, in the adjoining room
and must comply with the requisites of this
regulation.
1.10 FLUES/CHIMNEYS.
For the appliances with natural draught indi-
vidual chimneys and branched ues can be used.
Individual chimneys. e internal dimensions
of some types of individual chimneys are con-
tained within the prospects of the regulation. If
the eective system data do not fall within the
conditions of applicability or the table limits, the
size of the chimney must be calculated according
to the regulation.
Branched ues. In buildings with lots of oors,
branched flues can be used for the natural
draught evacuation of combustion products
(c.c.r.). New CCR must be designed following
the calculation method and regulationstandards.
Chimney caps. e cap is a device positioned
crowning an individual chimney or branched
ue. is device eases the dispersion of combus-
tion products, even in adverse weather condi-
tions, and prevents the deposit of foreign bodies.
is must satisfy the requisites of the regulation.
In order to prevent the formation of counter-
pressures that impede the discharge of combus-
tion products into the atmosphere, the outlet
height corresponding to the top of the chimney/
ue, independently of any caps, must be over the
“backow area”. It is therefore necessary to use
the minimum heights indicated in the gures
stated in the regulation, depending on the slope
of the roof.
Direct exhaust to the outside. The natural
draught appliances to be connected to a chimney
or a ue can discharge the combustion products
directly to the outside, through a pipe passing
through the perimeter walls of the building. In
this case discharge takes place through an exhaust
ue, which is connected to a draught terminal
at the outside.
Exhaust ue. e exhaust ue must be in com-
pliance with the same requisites listed for the
ue ducts, with further provisions stated in the
regulation in force.
Positioning the draught terminals. e draught
terminals must:
- be installed on external perimeter walls of the
building;
- be positioned according to the minimum dis-
tances specied in current technical standards.
Flue exhaust of forced draught appliances
in closed open-top environments. In spaces
closed on all sides with open tops (ventilation
pits, courtyards etc.), direct ue gas exhaust is
allowed for natural or forced draught gas ap-
pliances with a heating power range from 4 to
35kW, provided the conditions as per the current
technical standards are respected.
Important: it is prohibited to put the flues
exhaust control device out of order voluntarily.
Every piece of this device must be replaced using
original spare parts if they have deteriorated. In
the case of repeated interventions of the ues
exhaust control device, check the ues exhaust
ue and the ventilation of the room in which the
boiler is located.

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INSTALLATORUSER
MAINTENANCE TECHNICIAN
1.11 SYSTEM FILLING.
Once the boiler is connected, ll the system via
the lling valve (Fig. 2-2). Filling is performed
at low speed to ensure release of air bubbles in
the water via the boiler and heating system vents.
e boiler has a built-in automatic venting valve
on the circulator. Open the radiator vent valves.
Close radiator vent valves only when water es-
capes from them.
Close the lling valve when the boiler manometer
indicates approx. 1.2 bar.
N.B.: during these operations start up the cir-
culation pump at intervals, acting on the main
switch positioned on the control panel. Vent the
circulation pump by loosening the front cap and
keeping the motor running.
Tighten the cap aer the operation.
1.12 GAS SYSTEM STARTUP.
To start up the system, make reference to the
Standard.
In particular, for new gas systems:
- open windows and doors;
- avoid presence of sparks or naked ames;
- bleed all air from pipelines;
- check that the internal system is properly sealed
according to specications.
1.13 BOILER START UP IGNITION.
For issue of the envisioned Declaration of Con-
formity, the following must be performed for
boiler start-up (the following operations must
only be performed by an authorised company
and only in the presence of sta):
- check that the internal system is properly sealed
according to specications
- make sure that the type of gas used corresponds
to boiler settings;
- check that there are external factors that may
cause the formation of fuel pockets;
- switch the boiler on and check correct ignition;
- make sure that the gas ow rate and relevant
pressure values comply with those given in the
manual (par. 3.18);
- check the correct ventilation of the rooms;
- check the existing draught during normal
functioning of the appliance, e.g. a draught
gauge positioned at the exit of the appliance
Total head available to the system.
Total head (m H2O)
Flow rate (l/h)
Head (kPa)
A = Head available to the
system at maximum speed
with by-pass excluded.
B = Head available to the
system at maximum speed
with by-pass inserted.
C = Head available to the
system at second speed with
by-pass excluded.
D = Head available to the
system at second speed with
by-pass inserted.
combustion products;
- check that there is no backow of combustion
products into the room, even during function-
ing of fans;
- ensure that the safety device is engaged in the
event of gas supply failure and check activation
time;
- check activation of the main switch located
upstream from the boiler.
e boiler must not be started up even if only
one of the checks should be negative.
1.14 CIRCULATION PUMP.
e Mini Nike 24 3 E series boilers are supplied
with a built-in circulation pump with 3-posi-
tion electric speed control. e boiler does not
operate correctly with the circulation pump on
rst speed. To ensure optimal boiler operation,
in the case of new systems (single pipe and
module) it is recommended to use the pump
at maximum speed. e pump is already tted
with a condenser.
Pump release. If, aer a prolonged period of
inactivity, the circulation pump is blocked,
unscrew the front cap and turn the motor sha
using a screwdriver. Take great care during this
operation to avoid damage to the motor.
By-pass regulation (part. 20 Fig. 1-7). If neces-
sary, the by-pass can be regulated according to
system requirements from a minimum (by-pass
excluded) to a maximum (by-pass inserted)
represented by the graphics (Fig. 1-6).
Make the regulation using a at head screw-
driver, turn clockwise and insert the by-pass,
anti-clockwise it is excluded.
1.15 KITS AVAILABLE ON REQUEST.
• System shut o valves kit. e boiler is designed
for installation of system interception cocks
to be placed on ow and return pipes of the
connection assembly. is kit is particularly
useful for maintenance as it allows the boiler to
be drained separately without having to empty
the entire system.
• Polyphosphate dispenser kit. e polyphos-
phate dispenser reduces the formation of lime-
scale and preserves the original heat exchange
and domestic hot water production conditions.
e boiler is prepared for application of the
polyphosphate dispenser kit.
e above-mentioned kits are supplied complete
with instructions for assembly and use.

8
1-7
INSTALLATORUSER
MAINTENANCE TECHNICIAN
1.16 BOILER COMPONENTS.
Key:
1 - Flue hood
2 - System pressure switch
3 - Boiler pump
4 - Domestic hot water ow switch
5 - Gas valve
6 - Domestic hot water probe
7 - System lling valve
8 - Flue safety thermostat
9 - Flow probe
10 - Primary heat exchanger
11 - Safety thermostat
12 - Combustion chamber
13 - Ignition and detection electrodes
14 - System expansion vessel
15 - Burner
16 - Vent valve
17 - DHW heat exchanger
18 - ree-way valve (motorised)
19 - System draining valve
20 - By-pass
21 - 3 bar safety valve
N.B.: connection group (optional)

9
2-1
INSTALLATORUSER
MAINTENANCE TECHNICIAN
2INSTRUCTIONS FOR USE AND MAINTENANCE
2.1 CLEANING AND MAINTENANCE.
Attention: to preserve the boiler’s integrity
and keep the safety features, performance and
reliability, which distinguish it, unchanged over
time, you must at least execute maintenance
operations on a yearly basis in compliance
with what is stated in the relative point at “an-
nual check and maintenance of the appliance”,
in compliance with national, regional, or local
standards in force.
2.2 VENTILATION OF THE ROOMS.
In the room in which the boiler is installed it
is necessary that at least as much air ows as
that requested for by normal combustion of the
gas and ventilation of the room. e provisions
relative to ventilation, the ue pipes, chimneys
and caps are stated in Par. 1.8, 1.9 and 1.10. If in
doubt regarding correct ventilation, contact an
authorised company.
2.3 GENERAL WARNINGS.
Never expose the wall-mounted boiler to direct
vapours from a cooking surface.
Use of the boiler by unskilled persons or children
is strictly prohibited.
If temporary shutdown of the boiler is required,
proceed as follows:
a) drain the heating system if anti-freeze is not
used;
b) shut-o all electrical, water and gas supplies.
In the case of work or maintenance to structures
near ducting or devices for ue extraction and the
relative accessories, switch o the appliance and
on completion of the operations make sure that
an authorised company veries the eciency of
the ducting or the devices.
Never clean the appliance or connected parts
with easily ammable substances.
Never leave containers or ammable substances
in the same environment as the appliance.
It is prohibited and dangerous to obstruct the air
intake, even partially, for the ventilation of the
room in which the boiler is installed.
Due to the danger, functioning is also prohibited
in the same room as suction devices, chimneys
or similar at the same time as the boiler unless
there are additional openings dimensioned in a
way to satisfy the further necessity for air. For the
dimensioning of these additional openings, refer
to an authorised company. In particular, an open
re must have its own air supply.
On the contrary, the boiler cannot be installed
in the same room.
• Important: the use of components that employ
electrical power requires some fundamental
rules to be observed:
- do not touch the appliance with wet or moist
parts of the body; do not touch when barefoot;
- never pull electrical cables or leave the ap-
pliance exposed to atmospheric agents (rain,
sunlight, etc.);
- the appliance power cable must not be re-
placed by the user;
- - if the cable is damaged, switch off the
appliance and solely contact an authorised
company to replace it;
- if the appliance is not to be used for a certain
period, disconnect the main power switch.
At the end of its service life the appliance must
not be disposed of like normal household waste
nor discarded in the environment, but must be
removed by an authorised company. Contact the
manufacturer for disposal instructions.
2.4 CONTROL PANEL.
Key:
1 - Reset button
2 - Stand-by/O/Summer/Winter button
3 - ( ) button to increase
the domestic hot water temperature
4 - ( ) button to decrease
the domestic hot water temperature
5 - ( ) button to increase the system
water temperature
6 - ( ) button to reduce the system water
temperature
7 - Boiler manometer
8 - DHW production phase functioning*
active
9 - Boiler connected to remote control
(optional)
10 - Flame presence symbol and relative
power scale
11 - Functioning with external temperature
probe active (optional)
12 - Room central heating active phase
functioning
13 - Functioning in winter mode
14 - Functioning in summer mode
15 - Boiler in Stand-by mode
16 - Temperature and error code display
17 - Boiler in block does not require release
via “Reset” button

10
INSTALLATORUSER
MAINTENANCE TECHNICIAN
2.5 USING THE BOILER.
Before ignition, make sure the heating system
is lled with water and that the manometer (7)
indicates a pressure of 1 ÷ 1.2 bar.
- Open the gas cock upstream from the boiler.
- Press the button (2) until the display switches
on, aer which press the button in sequence
(2) and take the boiler to the summer ( )
or winter ( ) position.
• Summer ( ):in this mode the boiler func-
tions only to produce the DHW, the tempera-
ture is set via the buttons (3-4) and the relative
temperature is shown on the display via the
indicator (16).
• Winter ( ):in this mode the boiler functions
both for producing domestic hot water and
heating the environment. e temperature of
the DHW is always regulated via buttons (3-4),
the heating temperature is regulated via buttons
(5-6) and the relative temperature is shown on
the display via the indicator (16).
From this moment the boiler functions auto-
matically. With no demand for heat (heating or
domestic hot water production) the boiler goes to
“standby” function, equivalent to the boiler being
powered without presence of ame. Each time
the burner ignites, the relative ame present sym-
bol is displayed (10) with relative power scale.
• Operation with Comando Amico Remoto
remote controlV2 (CARV2) (Optional). If the
CARV2 is connected, the ( ) symbol will
appear on the display. e boiler regulation pa-
rameters can be set via the CARV2 control panel
and the reset button (1) remains active on the
boiler control panel, along with the switch-o
button (2) (“o” mode only) and the display
where the functioning state is shown.
Important: if the boiler is put into “o ” mode
on the CARV2 the “CON” connection error
symbol will appear on the CAR. e CARV2 is
however powered constantly so as not to loose
memorised programs.
• Functioning with optional external probe
( ).In the case of a system with optional
external probe, the boiler ow temperature for
room central heating is managed by the exter-
nal probe depending on the external tempera-
ture measured (Par. 1.8). e ow temperature
can be modied by selecting the functioning
curve via buttons (5 and 6), selecting a value
from “0 to 9” (Fig. 1-5).
With external probe present, the relative
symbol will appear on the display (12). In the
central heating phase, if the temperature of the
water contained in the system is sucient to
heat the radiators, the boiler can only function
with the activation of the pump.
• “Stand-by” mode. Press button (2) in suc-
cession until the ( ) symbol appears. e
boiler remains active from this moment and the
anti-freeze function, pump anti-block function
and 3-way and signalling of any anomalies is
guaranteed.
N.B.: in these conditions the boiler is consid-
ered still live.
• “O” mode. By holding the button (2) down
for 8 seconds, the display switches-o and the
boiler is o completely. e safety functions are
not guaranteed in this mode.
N.B.: in these conditions the boiler is consid-
ered still live even if there are no functions
active.
• Display functioning. e display lights up dur-
ing the use of the control panel, aer 15seconds
inactivity, the brightness drops until just the
active symbols are displayed. e lighting mode
can be varied via parameter P2 in the circuit
board customisation menu.
2.6 TROUBLESHOOTING.
e boiler signals out anomalies by ashing on
the display and relative error codes, listed on the
table, are displayed. On any remote control, the
error code will be displayed by the same numeric
code displayed according to the following exam-
ple (e.g. CARV2 = Exx).
Error
Code Anomaly signalled Cause Boiler status / Solution
01 No ignition block
In the event of request of room central heating or domestic hot water
production, the boiler does not switch on within the preset time. Upon
appliance commissioning or aer extended downtime, it may be neces-
sary to eliminate the block.
Press the Reset button (1)
02
Safety thermostat
block (overheat-
ing), ame control
anomaly
During normal operation, if a fault causes excessive overheating internally,
the boiler goes into overheating block. Press the Reset button (1)
03 Flue safety thermo-
stat anomaly e fume evacuation pipe does not function correctly.
e boiler goes into stand-by for 30
minutes, aer which, if normal work-
ing conditions are restored, it re-starts
without having to be reset. In the case
of 3 consecutive blocks, the boiler itself
blocks and it must be reset in order to
re-start. (1)
04 Generic boiler
P.C.B. anomaly Incorrect recognition of a signal by the boiler board microprocessor. Press the Reset button (1)
05 Flow probe
anomaly e board detects an anomaly on the ow probe. e boiler does not start (1)
06 Domestic hot water
probe anomaly e board detects an anomaly on the domestic hot water probe.
The anomaly is indicated, the boiler
continues to produce domestic hot water
but not with optimal performance. If an
anomaly occurs, antifreeze protection is
not guaranteed (1)
08 Maximum N° of
resets Number of allowed resets that have already performed.
Attention: the anomaly can be reset 5 con-
secutive times, aer which the function is
inhibited for at least one hour. One attempt
is gained every hour for a maximum of 5
attempts. By switching the appliance on and
o the 5 attempts are re-acquired.
(1) If the shutdown or fault persists, contact an authorised company (e.g. Authorised Technical Aer-Sales Service).
(2) Error codes over 31 are not shown on the CARV2 display.

11
INSTALLATORUSER
MAINTENANCE TECHNICIAN
Error
Code Anomaly signalled Cause Boiler status / Solution
10 Insucient system
pressure
Water pressure inside the central heating circuit that is sucient to guar-
antee the correct operation of the boiler is not detected.
Check on the boiler pressure gauge (1) that
the system pressure is between 1÷1.2 bar
and restore the correct pressure if necessary.
15 Conguration error If the board detects an anomaly or incongruity on the electric wiring, the
boiler will not start.
If normal conditions are restored the boiler
restarts without having to be reset. (1)
20 Parasite ame is occurs in the event of a leak on the detection circuit or anomaly in
the ame control unit. Press the Reset button. (1)
24 Push button control
panel anomaly e board detects an anomaly on the pushbutton panel.
If normal conditions are restored the
boiler restarts without having to be reset.
(1)
27 Insucient circula-
tion
is occurs if there is overheating in the boiler due to insucient water
circulating in the primary circuit; the causes can be:
- low system circulation; check that no shut-o devices are closed on the
central heating circuit and that the system is free of air (deaerated);
- blocked pump; free the pump.
Press the Reset button. (1)
31
Loss of remote
control communi-
cation.
This occurs if communication is lost between the boiler and the CARV2. Disconnect and reconnect the power to the
boiler. (1) (2)
37 Low power supply
voltage
This occurs when the power supply voltage is lower than the allowed
limits for the correct boiler operation.
If normal conditions are restored the boiler
restarts without having to be reset. (1) (2)
38 Loss of ame signal
This occurs when the boiler is ignited correctly and the burner flame
switches off unexpectedly; a new attempt at ignition is performed and
if normal conditions are restored, the boiler does not have to be reset.
If normal conditions are restored the boiler
restarts without having to be reset. (1) (2)
43
Block due to loss of
continuous flame
signal
This occurs if the ‘’Flame signal loss’’ error occurs 6 times consecu-
tively in 8.5 minutes (38)”. Press the Reset button. (1) (2)
(1) If the shutdown or fault persists, contact an authorised company (e.g. Authorised Technical Aer-Sales Service).
(2) Error codes over 31 are not shown on the CARV2 display.

12
2-2
INSTALLATORUSER
MAINTENANCE TECHNICIAN
2.7 BOILER SHUTDOWN.
For complete boiler switch-o, press the “o”
button, disconnect the onmipolar switch outside
of the boiler and close the gas cock upstream
from the appliance. Never leave the boiler
switched on if le unused for prolonged periods.
2.8 RESTORE CENTRAL HEATING
SYSTEM PRESSURE.
Periodically check the system water pressure.
e boiler pressure gauge should read a pressure
between 1 and 1.2 bar.
If the pressure is below 1 bar (with the circuit cool)
restore normal pressure via the cock located in the
lower part of the boiler (Fig. 2-2).
N.B.: close the cock aer the operation.
If pressure values reach around 3 bar the safety
valve may be activated.
In this case, remove water from an air vent valve
of a radiator until 1 bar is reached or ask for as-
sistance from an authorised company.
In the event of frequent pressure drops, contact
qualied sta for assistance to eliminate the pos-
sible system leakage.
2.9 SYSTEM DRAINING.
To drain the boiler, use the special draining
valve (Fig. 2-2)
Before draining, ensure that the lling valve is
closed.
2.10 ANTIFREEZE PROTECTION.
The boiler has an anti-freeze function that
switches on automatically when the temperature
falls below 4°C (standard protection to minimum
temperature of -5°C). In order to guarantee the
integrity of the appliance and the domestic hot
water heating system in zones where the tempera-
ture falls below zero, we recommend the central
heating system is protected using anti-freeze
liquid. In the case of prolonged inactivity (second
case), we also recommend that:
- disconnect the electric power supply;
- the central heating circuit and boiler domestic
hot water circuit must be drained. In systems
that are drained frequently, lling must be car-
ried out with suitably treated water to eliminate
hardness that can cause lime-scale.
Key:
1 - Filling valve
2 - Draining valve
Bottom view.
2.11 CASE CLEANING.
Use damp cloths and neutral detergent to clean
the boiler casing. Never use abrasive or powder
detergents.
2.12 DECOMMISSIONING.
In the event of permanent shutdown of the boiler,
contact professional sta for the procedures and
ensure that the electrical, water and gas supply
lines are shut o and disconnected.

13
3-1
INSTALLATORUSER
MAINTENANCE TECHNICIAN
3BOILER STARTUP INITIAL CHECK.
To commission the boiler:
- make sure that the type of gas used corresponds
to boiler settings;
- check connection to a 230V-50Hz power
mains, correct L-N polarity and the earthing
connection;
- make sure the central heating system is lled
with water and that the manometer indicates
a pressure of 1÷1.2 bar.
- switch the boiler on and check correct ignition;
- make sure the gas maximum, intermediate
and minimum ow rate and pressure values
correspond to those given in the handbook,
Par. 3.18;
- check activation of the safety device in the event
of no gas, as well as the relative activation time;
- check activation of the main switch located
upstream from the boiler;
- check the existing draught during normal
functioning of the appliance, e.g. a draught
gauge positioned at the exit of the appliance
combustion products;
- check that there is no backow of combustion
products into the room, even during function-
ing of fans;
- ensure activation of all adjustment devices;
- seal the gas ow rate regulation devices (if set-
tings are modied);
- check the production of domestic hot water;
3.1 HYDRAULIC DIAGRAM.
- check sealing eciency of water circuits;
- check ventilation and/or aeration of the instal-
lation room where provided.
If any checks/inspection give negative results, do
not start the boiler.
Key:
1 - Domestic hot water ow switch
2 - System lling valve
3 - Flow limiter
4 - Domestic hot water probe
5 - Gas valve
6 - System expansion vessel
7 - Burner
8 - Primary heat exchanger
9 - Flue hood
10 - Flue safety thermostat
11 - Safety thermostat
12 - Delivery probe
13 - Vent valve
14 - Boiler pump
15 - System draining valve
16 - System pressure switch
17 - DHW. heat exchanger
18 - ree-way valve (motorised)
19 - By-pass
20 - 3 bar safety valve
G - Gas supply
AC - Domestic hot water outlet
AF - Domestic cold water inlet
R - System return
M - System ow

14
3-2
5
1
2
6
5
4
3
4
4 5
11
7
7
7
12
12
7
13
13
11
5
7
4
10
10
10
10
9
8
INSTALLATORUSER
MAINTENANCE TECHNICIAN
3.2 WIRING DIAGRAM.
Key:
B1 - Flow probe
B2 - Domestic hot water probe
B4 - External probe
CAR V2 - Comando Amico Remoto remote
control Version 2 (optional)
DS1 - Display
E3 - Ignition and detection electrodes
E4 - Safety thermostat
E6 - Flue safety thermostat
F1 - Phase fuse
M1 - Boiler pump
M30 - ree-way valve
S2 - Selector switch functioning
S3 - Reset block key
S4 - Domestic hot water ow switch
S5 - System pressure switch
S20 - Room thermostat (optional)
S21 - Domestic hot water temperature
increase key
S22 - Domestic hot water temperature
decrease key
S23 - Heating temperature increase key
S24 - Heating temperature reduce key
e boiler is designed for application of a room
thermostat (S20), an On/O room chronother-
mostat, a program timer or a Comando Amico
Remoto remote controlV2 (CARV2). Connect
to clamps 40 - 41 eliminating the jumper X40,
paying attention not to invert the polarity if the
CARV2 is installed.
e connector X8 is used for the connection
of the Virgilio Palmtop in the microprocessor
soware updating operation.
3.3 TROUBLESHOOTING.
N.B.: maintenance interventions must be car-
ried out by an authorised rm (e.g. Technical
Assistance Service).
- Smell of gas. Caused by leakage from gas circuit
pipelines. Check sealing eciency of gas intake
circuit.
- Irregular combustion (red or yellow ame).
When the burner is dirty or the boiler lamellar
pack is blocked. Clean the burner or the boiler
lamellar pack.
- Frequent interventions of the over heat-
ing safety thermostat. It can depend on
the lack of water in the boiler, little water
circulation in the system or blocked pump.
Check on the manometer that the sys-
tem pressure is within established limits.
Check that the radiator valves are not closed
and also the functionality of the pump.
- e boiler produces condensate. is can be
caused by obstructions of the chimney or ues
with height or section not proportioned to the
boiler. It can also be determined by function-
ing at boiler temperatures that are excessively
low. In this case, make the boiler run at higher
temperatures.
- Frequent interventions of the ue safety ther-
mostat is can be caused by obstructions in
the ue gas circuit. Check the ue. e ue
may be obstructed or by height or section
not suitable for the boiler. Ventilation may be
insucient (see room ventilation point).
- Presence of air in the system. Check opening
of the hood of the special air vent valve (Fig.
1-7). Make sure the system pressure and expan-
sion vessel pre-charge values are within the set
limits; the pre-charge value for the expansion
vessel must be 1.0 bar, and system pressure
between 1 and 1.2 bar.
- Ignition block and Chimney block. (See par.
2.6 and 1.5 electric connection).
T1 - Low voltage feeder
T2 - Switch-on transformer
U1 - Rectier inside the gas valve
connector (Only available on
Honeywell gas valves)
X40 - Room thermostat jumper
Y1 - Gas valve
Y2 - Gas valve modulator
1 - User interface
2 - N.B.: e user interface is on
the welding side of the boiler
board
3 - 230 Vac 50Hz power supply
4 - Blue
5 - Brown
6 - Yellow/Green
7 - Black
8 - (DHW)
9 - (central heating)
10 - Grey
11 - White
12 - Red
13 - Green

15
INSTALLATORUSER
MAINTENANCE TECHNICIAN
3.4 INFORMATION MENU.
Pressing the buttons (3 and 4) for 5 seconds, the
“Information menu” is activated, which allows
to display some boiler functioning parameters.
To scroll through the various parameters, press
(3 and 4), to exit from the menu press buttons
(3 and 4) again for 5 seconds or press button (2)
for 5 seconds or wait for 60 seconds.
List of parameters.
N°
parameter
Description
d1 Displays the ame signal (uA).
d2
Displays the primary exchanger
output instant heating ow
temperature.
d3
Displays the instant output
temperature from the DHW
exchanger.
d4
Displays the temperature set for
the central heating set (if remote
control is present).
d5
Displays the temperature set for
the DHW set (if remote control
is present).
d6
Displays the external environ-
ment temperature (if the exter-
nal probe is present).
If the temperature is below zero,
the value is displayed ashing.
3.5 PROGRAMMING THE P.C.B.
e boiler is prepared for possible programming of
several operation parameters. By modifying these
parameters as described below, the boiler can be
adapted according to specic needs.
To access the programming phase, proceed as
follows:
- press buttons (1) and (2) at the same time for
approximately 8 seconds;
- Using buttons (3) and (4), select the parameter
to be changed indicated in the following table:
List of
param-
eters
Description
P1 Boiler mode (DO NOT USE)
P2 Display lighting
P3 DHW thermostat
P4 Minimum CH output
P5 Maximum CH output
P6 Central heating ignitions timer
P7 Central heating ramp timer
P8
Heating switch-on delay
request from room thermostat
and remote control
P9 Solar mode
- adjust the corresponding value consulting the
table using buttons (5) and (6);
- conrm the set value pressing the Reset button
(1) for approximately 3 seconds; by pressing
keys (3) and (4) at the same time exit the func-
tion without memorising the modications
made.
N.B.: aer a period of time, without touching
any keys, the operation cancels automatically.
Boiler mode. It establishes whether the boiler
functions in instant or storage mode.
Boiler mode (P1)
Range of values which can
be set
Standard
setting
0 - instant boiler
1 - boiler with storage tank 0
Illumination display. Determines how display
illumination.
Display lighting (P2)
Range of values which can
be set
Standard
setting
0 - O
1 - Auto
2 - On
1
- O: the display is always lit with low intensity.
- Auto: the display lights up during use and low-
ers aer 15 seconds of inactivity. In the case of
anomaly the display ashes.
- On: the display is always lit with high intensity.
DHW thermostat. With the “correlated” ther-
mostat setting, boiler switch-o takes place on
the basis of the temperature set. While with
the setting of the “xed” DHW thermostat the
switch-o temperature is xed at the maximum
value independently from the value set on the
control panel.
DHW thermostat (P3)
Range of values which can
be set
Standard
setting
0 - Fixed
1 – Correlated 1
Heating output. e boiler also has electronic
modulation that adapts the boiler potentiality to
the eective heating demand of the house. en
the boiler works normally in a variable gas pres-
sure eld between the minimum heating power
and the maximum heating power depending on
the system’s heating load.
N.B.: the boiler is produced and calibrated in
the central heating phase at nominal output.
Approximately 10 minutes are needed to reach
the nominal heat output, which can be changed
using the parameter (P5).
N.B.: the selection of the “Minimum heating
power” and “Maximum heating power” param-
eters, in the presence of a heating request, allows
switch-on of the boiler and power supply of the
modulator with current equal to the value of the
respective set value.
Minimum central heating output (P4)
Range of values which can
be set
Standard
setting
0 - 63 %
Set
according
to factory
inspection
Maximum heating output (P5)
Range of values which can
be set
Standard
setting
0 - 99 % 99
Central heating ignitions timer. e boiler has
electronic timing, which prevents the burner
from igniting too oen in central heating mode.
Central heating ignitions timer (P6)
Range of values which can
be set
Standard
setting
0 - 20 (0 - 10 minutes)
(01 equals 30 seconds)
6
(3’)
Central heating ramp timing. In the ignition
phase, the boiler performs an ignition ramp in
order to arrive at the maximum power set.
Central heating ramp timer (P7)
Range of values which can
be set Parameter
0 - 28 (0 - 14 minutes)
(01 equals 30 seconds)
28
(14’)

16
43
2
1
56
3-3
4
3
2
1
6
5
INSTALLATORUSER
MAINTENANCE TECHNICIAN
Heating switch-on delay request from room
thermostat and remote control. e boiler is
set to switch-on immediately aer a request. In
the case of particular systems (e.g. area systems
with motorised thermostatic valves etc.) it could
be necessary to delay switch-on.
Heating switch-on delay request from
room thermostat and remote control (P8)
Range of values which can
be set Parameter
0 - 20 (0 - 10 minutes)
(01 equals 30 seconds)
0
(0’)
DHW ignition delay. e boiler is set to switch-
on immediately aer a request. for DHW In
the case of coupling with solar storage tanks
positioned upstream from the boiler, it is pos-
sible to compensate the distance of the storage
tank in order to allow the hot water to reach the
utility, setting the necessary time and therefore
verifying that the water is hot enough (see Par.
Solar panels coupling).
Solar mode (P9)
Range of values which can
be set
Standard
setting
0 - 20 seconds 0
Gas type selection. e setting of this function
is used to adjust the boiler in order to function
with the correct type of gas.
To access this regulation, once having entered the
programming mode, press the button (2) for 4
seconds. To exit, press button (2) again 4seconds.
Gas type selection (G1)
Range of values which can
be set
Standard
setting
nG - Methane
lG - LPG
Ci - China
e same
as the type
of gas be-
ing used
Ignition power (G2)
Range of values which can
be set
Standard
setting
0 - 70 %
Set
according
to factory
inspection
3.6 CONVERTING THE BOILER TO
OTHER TYPES OF GAS.
If the boiler has to be converted to a dierent gas
type to that specied on the data plate, request
the relative conversion kit for quick and easy
conversion.
e gas conversion operation must be carried
out by an authorised rm (e.g. Technical As-
sistance Service).
To convert to another type of gas the following
operations are required:
- remove the voltage from the appliance;
- replace the main burner injectors, making sure
to insert the special seal rings supplied in the
kit, between the gas manifold and the injectors;
- apply voltage to the appliance;
- use the boiler push button control panel to
select the gas parameter type (G1) and select
(Ng) in case of Methane supply or (Lg) in the
case of LPG;
- adjust the boiler nominal heat output;
- adjust the boiler minimum heat power;
- adjust the boiler nominal heat output in heating
phase;
- adjust (eventually) the maximum heating
power;
- seal the gas ow rate regulation devices (if set-
tings are modied);
- aer completing conversion, apply the sticker,
present in the conversion kit, near to the data-
plate. Using an indelible marker pen, cancel the
data relative to the old type of gas.
ese adjustments must be made with reference
to the type of gas used, following that given in
the table (par. 3.18).
3.7 CHECKS FOLLOWING
CONVERSION TO ANOTHER TYPE
OF GAS.
Aer making sure that conversion was carried
out with a nozzle of suitable diameter for the
type of gas used and the settings are made at the
correct pressure, check that:
- there is no ame in the combustion chamber
- the burner ame is not too high or low and that
it is stable (does not detach from burner)
- the pressure testers used for calibration are
perfectly closed and there are no leaks from
the gas circuit.
N.B.: all boiler setting operations must be car-
ried out by an authorised rm (e.g. Technical
Assistance Service). Burner adjustment must
be carried out using a dierential “U” or digital
type manometer connected to the gas valve outlet
pressure point (part.4 Fig.3-3), keeping to the
pressure value given in the table (Par. 3.18) ac-
cording to the type of gas for which the boiler
is prepared.
SIT 845 GAS valve
Key:
1 - Coil
2 - Minimum power adjustment nut
3 - Maximum power adjustment nut
4 - Gas valve outlet pressure point
5 - Gas valve inlet pressure point
6 - Protection hood
VK 4105 M GAS valve

17
INSTALLATORUSER
MAINTENANCE TECHNICIAN
3.8 POSSIBLE ADJUSTMENTS.
N.B.: to adjust the gas valve, remove the plastic
cap (6); aer adjusting, ret the cap.
• Preliminary calibration operations.
- Set parameter P4 at 0 %.
- Set parameter P5 at 99 %.
• Activate the chimney sweep function.
- Enter the “DHW chimney sweep” mode,
opening a DHW cock.
• Adjustment of boiler nominal thermal heat
output.
- Set the maximum output (99%) using the
buttons (5 and 6 Fig. 2-1).
- Adjust the boiler nominal power on the brass
nut (3 Fig. 3.3), keeping to the maximum
pressure values stated in the tables (Par.3.18)
according to the type of gas; by turning
clockwise the heat potential increases, anti-
clockwise it decreases.
• Adjustment of boiler minimum thermal heat
output.
N.B.: only proceed aer having calibrated the
nominal pressure.
- Set the minimum output (0%) always using
the buttons (5 and 6 Fig. 2-1).
- Adjust the minimum thermal input by op-
erating on the cross plastic screws (2) on the
gas valve maintaining the brass nut blocked
(3);
• Exit the “Chimney sweep” mode and keep the
boiler functioning.
• Adjustment of the boiler minimum heat output
in heating phase.
N.B.: only proceed aer having calibrated the
minimum boiler pressure.
- To adjust the minimum heat output during
the heating phase, change parameter (P4),
increasing the value the pressure increases,
reducing it the pressure drops.
- e pressure to which the boiler minimum
heat output must be adjusted, must not be
lower than that stated in the tables (Par.3.18).
• Adjustment (any) of the boiler maximum heat
output in heating phase.
- To adjust the maximum heat output during
the heating phase, change parameter (5),
increasing the value the pressure increases,
reducing it the pressure drops.
- e pressure to which the boiler maximum
heat output must be adjusted in central heat-
ing phase, must not be carried out in refer-
ence to that stated in the tables (Par. 3.18).
3.9 AUTOMATIC SLOW IGNITION
FUNCTION WITH TIMED RAMP
DELIVERY.
In ignition phase, the P.C.B. supplies constant
gas with pressure proportional to the parameter
“G2” set.
3.10 CHIMNEY SWEEP” FUNCTION.
When activated, this function forces the boiler
to variable output for 15 minutes.
In this state all adjustments are excluded and only
the safety thermostat and the limit thermostat
remain active. To activate the chimney sweep
function, press the Reset button (1) for 8 seconds
in absence of DHW requests, its activation is sig-
nalled by the indication of the ow temperature
and the ashing and symbols.
is function allows the technician to check
the combustion parameters. Once the function
is activated, it is possible to select whether to
perform the check in CH status, regulating the
parameters with buttons (5 and 6) or in DHW
mode opening any DHW cock and always regu-
late the parameters with the buttons (5 and 6).
Functioning in CH or DHW mode is visualised
by the relative ashing or symbols.
On completion of the checks, deactivate the
function by pressing the Reset button (1) for
8 seconds.
3.11 PUMP ANTIBLOCK FUNCTION.
e boiler has a function that starts the pump
once every 24 hours for the duration of 30
seconds in order to reduce the risk of the pump
becoming blocked due to prolonged inactivity.
3.12 THREEWAY ANTIBLOCK
FUNCTION.
The boiler is supplied with a function that
activates the motorises three-way unit every
24hours, carrying out a complete cycle in order
to reduce the risk of three-way block due to
prolonged inactivity.
3.13 RADIATORS ANTIFREEZE
FUNCTION.
If the system return water is below 4°C, the boiler
starts up until reaching 42°C.
3.14 P.C.B. PERIODICAL SELFCHECK.
During functioning in central heating mode or
with boiler in stand-by, the function activates
every 18 hours aer the last boiler check/power
supply. In case of functioning in domestic hot wa-
ter mode the self-check starts within 10 minutes
aer the end of the withdrawing in progress, for
duration of approx. 10 seconds.
N.B.: during self-check, the boiler remains o,
including signalling.
3.15 SOLAR PANELS COUPLING
FUNCTION.
e boiler is set-up to receive pre-heated water
from a system of solar panels up to a maximum
temperature of 65°C. In all cases, it is always
necessary to install a mixing vale on the hy-
draulic circuit upstream from the boiler on the
cold water inlet.
Note: for good functioning of the boiler; the
temperature selected on the solar valve must
be 5 °C greater with respect to the temperature
selected on the boiler control panel.
For correct use of the boiler in this condition,
parameter P3 (DHW thermostat) must be set at
“1” and the parameter P9 (DHW ignition delay)
at a temperature sucient to receive water from
a storage tank situated upstream from the boiler.
e greater the distance from the storage tank,
the longer the stand-by time to be set. When
these regulations have been performed, when
the boiler inlet water is at the same or greater
temperature with respect to that set by the DHW
selector switch, the boiler does not switch on.

18
3-4
1
3
3
2
a
b
b
c
a
1
INSTALLATORUSER
MAINTENANCE TECHNICIAN
a
1
Installation drawings key:
Unmistakable component identication
Sequential identication of the operation to perform
3.16 CASING REMOVAL.
To facilitate boiler maintenance the casing can be
completely removed as follows: (Fig. 3-4 / 3-5):
1 Unhook the decorative frame (a) from the
relative lower retainers.
2 Remove the decorative frame (a) from the cas-
ing (c).
3 Loosen the 2 front screws (b) for xing the
casing.
4 Loosen the 2 lower screws (d) for xing the
casing.
5 Pull the case towards yourself (c).
6 Push the case (c) upwards at the same time to
release it from the upper hooks.

19
3-5
4
4
5
6
6
d
d
c
INSTALLATORUSER
MAINTENANCE TECHNICIAN

20
INSTALLATORUSER
MAINTENANCE TECHNICIAN
3.17 YEARLY APPLIANCE CHECK AND
MAINTENANCE.
e following checks and maintenance should
be performed at least once a year.
- Clean the ue side of the heat exchanger.
- Clean the main burner.
- Visually check the ue hood for deterioration
or corrosion.
- Check correct lighting and functioning.
- Check correct calibration of the burner in
domestic hot water and central heating phases.
- Check correct functioning of control and
adjustment devices and in particular:
- the intervention of main electrical switch
positioned outside of the boiler;
- system control thermostat intervention;
- domestic hot water control thermostat inter-
vention.
- Check sealing eciency of the gas circuit and
the internal system.
- Check the intervention of the device against no
gas ionisation ame control. Intervention time
must be less than 10 seconds.
- Visually check for water leaks or oxidation
from/on connections.
- Visually check that the water safety drain valve
is not blocked.
- Check that, aer discharging system pressure
and bringing it to zero (read on boiler manom-
eter), the expansion vessel load is at 1.0 bar.
- Check that the system static pressure (with
system cold and aer relling the system by
means of the lling valve) is between 1 and
1.2bar.
- Visually check that the safety and control
devices have not been tampered with and/or
shorted, in particular:
- temperature safety thermostat;
- water pressure switch,
- ue exhaust control thermostat.
- Check the condition and integrity of the electri-
cal system and in particular:
- electrical power cables must be inside the
whipping;
- there must be no traces of blackening or
burning.
N.B.: in addition to yearly maintenance, the ther-
mal system must also be checked, with frequency
and procedures that comply with the provisions
of the technical regulations in force.
N.B.: Gas ow rates refer to heating power be-
low a temperature of 15°C and at a pressure of
1013 mbar. Burner pressure values refer to use
of gas at 15°C.
3.18 VARIABLE HEAT OUTPUT.
METHANE (G20) BUTANE (G30) PROPANE (G31)
HEAT
OUTPUT
HEAT
OUTPUT
HEAT
+
DHW
BURNER GAS
FLOW RATE
PRESS. NOZZLES
PRESSURE
BURNER GAS
FLOW RATE
PRESS. NOZZLES
PRESSURE
BURNER GAS
FLOW RATE
PRESS. NOZZLES
PRESSURE
(kW) (kcal/h) (m3/h) (mbar) (mm H2O) (kg/h) (mbar) (mm H2O) (kg/h) (mbar) (mm H2O)
23.8 20468 2.77 14.00 142.8 2.07 27.70 282.5 2.03 35.70 364.0
23.0 19780 2.67 13.05 133.0 2.00 25.95 264.6 1.96 33.43 340.9
22.0 18920 2.56 11.92 121.5 1.91 23.86 243.3 1.88 30.74 313.4
21.6 18550 2.51 11.45 116.8 1.87 22.99 234.5 1.84 29.62 302.1
20.0 17200 2.33 9.86 100.5 1.74 20.00 204.0 1.71 25.76 262.7
19.0 16340 2.22 8.92 90.9 1.66 18.22 185.8 1.63 23.46 239.3
18.0 15480 2.11 8.03 81.9 1.57 16.54 168.7 1.55 21.29 217.1
17.0 14620 2.00 7.20 73.4 1.49 14.94 152.4 1.47 19.22 196.0
16.0 13760 1.89 6.42 65.5 1.41 13.43 137.0 1.38 17.27 176.1
15.0 12900 1.77 5.70 58.1 1.32 12.00 122.4 1.30 15.43 157.3
14.0 12040 1.66 5.02 51.2 1.24 10.65 108.6 1.22 13.68 139.5
13.0 11180 1.55 4.39 44.8 1.16 9.38 95.6 1.14 12.04 122.8
12.0 10320 1.44 3.81 38.8 1.08 8.18 83.4 1.06 10.50 107.0
11.0 9460 1.33 3.27 33.4 0.99 7.06 72.0 0.98 9.05 92.2
10.0 8600 1.22 2.78 28.4 0.91 6.01 61.3 0.89 7.69 78.4
9.5 8170 1.16 2.55 26.1 0.87 5.51 56.2 0.85 7.05 71.9
9.4 8084 1.15 2.51 25.6 0.86 5.41 55.2 0.85 6.92 70.6
7.0 6020 DHW 0.88 1.60 16.3 0.65 3.30 33.7 0.64 4.20 42.8