Unical NOVAIREX Series User manual

INSTALLATION AND MAINTENANCE INSTRUCTIONS
NOVAIREX
35 - 45 - 55

2
Attention: this manual contains instructions for the exclusive use of the pro-
fessionally qualified installer and/or maintenance technician in compliance
with current legislation.
The system manager is NOT authorised to service the boiler.
The manufacturer will not be held liable in case of damage to persons, animals
or objects resulting from failure to comply with the instructions contained in
the manuals supplied with the boiler.

3
-
1 GENERAL INFORMATION ................................................................................................................................................................................... 4
1.1 General warnings.......................................................................................................................................................................................... 4
1.2 Symbols used in the manual......................................................................................................................................................................... 5
1.3 Appropriate use of appliance ........................................................................................................................................................................ 5
1.4 Information for system manager ................................................................................................................................................................... 5
1.5 Safety warnings ............................................................................................................................................................................................ 6
1.6 Technical data plate ...................................................................................................................................................................................... 7
General informationTechnical featuresInstallation instructionsMaintenance instructions
4 INSPECTION AND MAINTENANCE ................................................................................................................................................................53
Inspection and maintenance instructions........................................................................................................................................................... 53
Maintenance of the body ................................................................................................................................................................................... 54
Cleaning and routine maintenance .................................................................................................................................................................... 54
Maintenance operations .................................................................................................................................................................................... 54
3 INSTRUCTIONS FOR THE INSTALLER................................. 15
3.1 General warnings ............................................................ 15
3.2 Installation rules .............................................................. 15
3.3 Installation on old systems or to be renovated ................ 15
3.4 Packaging........................................................................ 16
3.5 Transport ......................................................................... 16
3.6 Installation ...................................................................... 17
3.7 Connecting the boiler to the system ................................ 18
3.8 Water connections ........................................................... 18
3.9 Connection to the flue...................................................... 23
3.10 Electrical connections...................................................... 26
3.11 Connections..................................................................... 27
3.12 Reference plumbing diagrams......................................... 28
3.13 Panel board ..................................................................... 39
3.14 Filling the system............................................................. 45
3.15 Starting the boiler ............................................................ 46
3.16 Summer operation ........................................................... 49
3.17 Warnings ......................................................................... 49
2 TECHNICAL FEATURES AND DIMENSIONS ...................................................................................................................................................8
2.1 Technical features......................................................................................................................................................................................... 8
2.2 Dimensions and plumbing connections ........................................................................................................................................................ 9
2.3 Technical data............................................................................................................................................................................................. 10
2.4 Main components ....................................................................................................................................................................................... 11
2.5 General ....................................................................................................................................................................................................... 11
2.6 Features of the wood .................................................................................................................................................................................. 14
3.18 Troubleshooting ............................................................... 50
3.19 Alarm diagram and problem solving................................ 51
3.20 Audible alarms................................................................. 52

4
1GENERAL INFORMATION
1.1 - GENERAL WARNINGS
The instruction booklet is an integral and essential part of the
product and must be kept by the system manager.
Read the warnings contained in this instruction booklet carefully
as they provide important guidelines regarding installation, use
and maintenance safety.
Keep the booklet with care for further consultation.
Your appliance must be installed and serviced in compliance
with the standards in force according to the manufacturer
instructions, up to standard and by legally qualified and
certified personnel.
Systems for the production of domestic hot water MUST be
constructed entirely with materials that comply with M.D.
174/2004 (taps, pipes, fittings, etc.).
By professionally qualified personnel we mean: personnel
with specific technical skill in the field of heating system
components for civil use, domestic hot water production
and maintenance. Personnel must have the qualifications
provided for by current legislation.
Incorrect installation or improper maintenance can cause dam-
age to persons, animals or objects for which the manufacturer
is not responsible.
Before performing any cleaning or maintenance, disconnect the
appliance from the energy mains by acting on the switch of the
system and/or through the specific cut-off devices.
Do not obstruct the terminals of the ventilation ducts.
In case of failure and/or malfunctioning of the appliance, switch
it off and do not try to repair it or intervene on it directly. Contact
only personnel qualified in compliance with law.
Any product repairs must be performed solely by personnel
authorised by Unical, using original spare parts only. Failure to
comply with the above can compromise the safety of the appli-
ance and void the warranty.
To guarantee appliance efficiency and its correct operation,
yearly maintenance must be performed by qualified personnel.
Should you decide not to use the appliance, parts entailing
potential sources of hazard must be made safe.
Should the appliance be sold or transferred to a new owner or
if you move and leave the appliance, always make sure that the
instruction manual accompanies it in order to be consulted by
the new owner and/or installer.
Only original accessories must be used for all appliances with
optionals or kits (including electric).
This appliance is intended solely for the use for which it was
expressly designed.
Any other use is to be considered improper and therefore dan-
gerous.

5
General information
1.2 - SYMBOLS USED IN THE MANUAL
Pay special attention when reading this manual to the parts marked by the symbols:
1.3 -APPROPRIATE USE OF THE APPLIANCE
The NOVAIREX appliance has been constructed according to the current level of engineering and acknowl-
edged technical safety rules.
Nonetheless, if improperly used, dangers could arise for the safety and life of the user and other persons
or damage to the equipment or other objects.
The appliance is intended to operate in hot water circulation heating systems.
Any other use must be considered improper.
UNICAL will not be held liable for any damage resulting from improper use.
Use according to the intended purposes also includes strict compliance with the instructions in this manual.
The user must be instructed concerning the use and operation of his heating system, in particular:
• Deliver these instructions to the user, as well as other documents concerning the appliance inserted in the envelope
inside the packaging. The user must keep this documentation safe for future consultation.
• Inform the user about the importance of the air vents and the flue gas exhaust system, highlighting their essential
features and the absolute prohibition of modifying them.
• Inform the user concerning controlling the system's water pressure as well as operations to restore it.
• Inform the user concerning correct temperature control, control units/thermostats and radiators for saving energy.
• Remember that the system must receive regular maintenance at least once a year and combustion analysis must
be performed every two years (as per national law).
• Should the appliance be sold or transferred to a new owner or if you move and leave the appliance, always make
sure that the instruction manual accompanies it in order to be consulted by the new owner and/or installer.
The manufacturer will not be held liable in the event of damage to persons, animals or objects resulting from
failure to comply with the instructions contained in this manual.
1.4 - INFORMATION FOR SYSTEM MANAGER
NOTE!
Tips
for the user
ATTENTION!
Possible dangerous
situation for the product
and the environment
DANGER!
Serious danger for
personal safety and life

6
1.5 - SAFETY WARNINGS
ATTENTION!
The appliance must be installed, adjusted and maintained by professionally qualified personnel, in com-
pliance with the standards and provisions in force. Incorrect installation can cause damage to persons,
animals and objects for which the manufacturer cannot be held responsible.
DANGER!
The boiler must be serviced or repaired by professionally qualified personnel, authorised by Unical. We
recommend stipulating a maintenance contract.
Insufficient or irregular maintenance can jeopardise the operating safety of the appliance and cause damage
to persons, animals and objects for which the manufacturer cannot be held responsible.
Modifying parts connected to appliance
Do not modify the following parts:
- the boiler
- the air, water and electrical current lines
- the flue gas pipe, the safety valve and the exhaust pipe
- the construction parts which affect the operating safety of the appliance
Attention!
To tighten or loosen the screwed fittings, use only appropriate fixed spanners.
Incompliant use and/or inappropriate tools can cause damage (e.g. water or gas leakage).
Explosive and easily flammable substances
Do not use or store explosive or easily flammable materials (e.g. petrol, paints, paper) in the room where the ap-
pliance is installed.
ATTENTION!
The appliance must not be used by people with reduced physical, sensory and mental abilities, without
experience and knowledge. These people must be previously trained and supervised during manoeuvre
operations. Children must be supervised so that they do not play with the appliance.

7
General information
1.6 - TECHNICAL DATA PLATE
The technical data plate is adhesive and is included in the
document case; it must be applied by the installer on the
outside of the casing.
The serial number of the boiler is on the riveted plaque on
the front plate of the body (front right top side).

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2TECHNICAL FEATURES
AND DIMENSIONS
2.1 - TECHNICAL FEATURES
The heat generator mod. NOVAIREX is a steel boiler running
with natural wooden logs, total gasification, inverted flame, with
combustion chamber under negative pressure.
It is supplied in the following models:
NOVAIREX 34
NOVAIREX 45
NOVAIREX 55
The NOVAIREX boiler is complete with all the safety and control
devices required by relevant standards.
DESCRIPTION OF COMPONENTS:
• Steel boiler body with combustion chamber partially covered
with refractory material
• Burner in refractory material
• Horizontal smoke ducts
• Front door for loading wood covered with refractory material
• Bottom door covered with refractory material, complete with
combustion air adjustments and fitted with flame sight glass
• Rear smoke chamber with side inspection and ash removal
doors
• Flue gas extraction with intake modulating fan
• Safety heat exchanger
• Boiler body insulated with 50 mm thick mineral wool panels
• Powder painted sheet steel casing
PANEL BOARD COMPONENTS:
• Main switch with light indicating presence of power
• Safety thermostat for boiler overheating
• Main fuse
• Display

9
Technical features
2.2 - HYDRAULIC DIMENSIONS AND CONNECTIONS
T7 -T8
1. Panel board
2. Primary air adjustment
3. Secondary air adjustment
4. Flame sight glass
5. Cleaning doors
6. Rear smoke chamber
7. Loading door
8. Modulating fan
9. Bottom inspection and cleaning door
DIMENSIONS
A
B
C
D
E
F
G
510
680
610
680
610
880
1230 1380
190
81
190
78
1025
628
1380
190
81
11501150
628 828
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)
CONNECTIONS T1 - T2
T5
T6
T3 - T4 - T7 - T8
UNI ISO 228/1
(Ø mm)
UNI ISO 228/1
G 1¼
150
G ½
G ½
G 1½
200
G ½
G ½
UNI ISO 228/1
H65 65
(mm)
G 1½
200
G ½
G ½
65
NOVAIREX 34 NOVAIREX 45 NOVAIREX 55
T1. Central heating flow
T2. Central heating return
T3. Safety thermostat probe bulb holder, boiler flow probe
T4. Connection for any temperature relief valve probe bulb
holder
T5. Chimney connection
T6. Safety heat exchanger connections
T7. Boiler drain
T8. Return probe connection

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MODELS NOVAIREX 34 NOVAIREX 45 NOVAIREX 55
MAXIMUM NOMINAL OUTPUT* (kW) 30.61 40.09 49.10
FURNACE MAXIMUM OUTPUT (kW) 34.2 45.05 55.16
* Power achieved with good quality wood with 15% humidity content.
** Considering a thermal power requirement of 30 kcal/m3
WATER SIDE PRESSURE DROPS (10K)
WATER SIDE PRESSURE DROPS (20K)
BOILER WATER CONTENT
EMPTY BOILER WEIGHT
MAXIMUM OUTPUT
OUTPUT IN STAND-BY
BOILER CLASS ACCORDING TO EN 303-5
(m.w.c.) 0.2 0.4 0.5
0.070.070.05
(m.w.c.)
(l)
(kg)
(W)
(W)
59
363
146
5
71
475
146
5
93
623
146
5
5 5 5
DURATION OF COMBUSTION
WOOD STORAGE VOLUME
MAX OPERATING PRESSURE
LOADING OPENING
LOG LENGTH
(h) 5 6 6
218160108
(l)
(bar)
(mm)
(cm)
3
334 x 419
50
3
434 x 519
50
3
434 x 519
70
NOISE LEVEL (dB) <50 <50 <50
MINIMUM DRAUGHT REQUIRED BY CHIMNEY (Pa) 20 20 20
MIN. FLOW TEMPERATURE (°C) 70 70 70
MAX. FLOW TEMPERATURE (°C) 85 85 85
MIN. RETURN TEMPERATURE (°C) 55 55 55
NOMINAL LOADING FLUE TEMPERATURE (°C) 171 177 178
NOMINAL LOADING FLUE GAS MASS FLOW RATE (kg/s) 0.02 0.026 0.032
EFFICIENCY (%) 89.5 89.0 89.0
O2 (%) 4.73 5.05 6.12
CO2 (%) 13.9 13.74 13.6
2.3 - TECHNICAL DATA
CO 10% (mg/Nm3)361 469 367
CO 13% (mg/Nm3)263 342 267
NOx 10% (mg/Nm3)216 213 220
NOx 13% (mg/Nm3)157 155 160
Hc 10% (mg/Nm3)1 10 11
Hc 13% (mg/Nm3)1 8 8
Dust 10% (mg/Nm3)28 29 29
Dust 13% (mg/Nm3)21 21 21
FUEL CHARACTERISTICS See par. 2.7
THERMAL STORAGE VOLUME
(If Qmin > 30% of Qn)
(l) 1683 2205 2700
MAX. SUPPLY WATER TEMPERATURE
SAFETY HEAT EXCHANGER
(°C) 15 15 15
SUPPLY WATER PRESSURE
SAFETY HEAT EXCHANGER
(bar) 2 2 2
BOILER OPERATION WITH FAN
COMBUSTION CHAMBER OPERATION UNDER NEGATIVE PRESSURE
OPERATION IN CONDENSATION NO
MAXIMUM HEATABLE VOLUME ** (m3)900 1179 1444

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Technical features
2.4 - MAIN COMPONENTS
2.5 - GENERAL
1. Panel board
2. Top cover
3. 2 side panels
4. Anti-smoke door
5. Wood storage door with refractory material and gasket
6. Primary and secondary air adjustment unit
7. Fan
8. Combustion chamber door with
refractory material, gasket, flame sight glass
9. Thick steel combustion chamber
10. Heat exchange fin
11. Boiler drain
12. Safety heat exchanger
13. Boiler body insulation in mineral wool
14. Steel boiler body
15. Burner built with refractory material with bars and grate
16. Smoke chamber
17. By pass
M Heating system flow
R Heating system return
N.B.: The fire bars and the refractory steel grate are subject to wear; it is therefore
advisable to carry out an annual inspection to prevent faulty boiler operation.
A BRIEF SUMMARY OF INVERTED
FLAME COMBUSTION
Everybody knows that to make a match last it must be held with
its head upwards. This is because in its convective motion, the
flame must not meet fuel other than that which has generated it.
As in residential heating the fuel is usually in the form of wood
logs which are loaded from the top, the flame has to go in the
opposite direction, i.e. downwards.
Natural draught is a source of negative pressure which varies
greatly depending on the type of chimney, on weather conditions,
on the type of fuel, etc.
Therefore it is necessary to integrate it with a forced ventilation
unit to stabilise its effects.
By fitting a fan it is possible to considerably reduce the section
of the gas ducts on the grate and furthermore there are no
problems with cold starts.
The small grate permits more controlled passage of combustion
air, contrarily to what happens with large traditional grates.
The air can be perfectly adjusted because the grate, covered
with burning wood, has the same crossing resistance and thus
combustion will always be optimal.
Unical has already used this principal for many years with the
Gasogen boiler.

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NOVAIREX BOILER STRUCTURE
The boiler body is composed of two oval elements placed one
inside the other, so that a water cavity is created between the two.
The large capacity wood storage has a special thermal and
mechanical high resistance refractory press, for the purpose of
keeping the by-pass area dry in all operating conditions.
The following parts can be distinguished:
1. Wood storage, drying zone
2. Gasification zone
3. Embers zone
4. Burner in refractory material
5. Combustion chamber
6. Heat exchange surface
7. Cradle in refractory material
8. Boiler water
9. Safety heat exchanger
M System hot water flow
R System return
GASIFICATION ZONE (2)
Gasification takes place in the lower part of the firewood storage.
It is very important for gasification to be as regular as possible,
so as not to overload the burner with gas.
Gasification speed depends on the amount of fuel and the size
of the drying area. Generally, it is better to use large logs if they
are dry and small logs if the wood is moist. The quantity of pri-
mary air, proportional to the delivered output, is regulated via
the adjustment system.
EXCHANGE SURFACE (6)
Operating on wood and without very high sulphur percentages,
it is important to achieve very low flue temperatures to improve
water efficiency. Accordingly, a dry-passage exchange surface
was adopted, which is already well-tested for diesel-fired boilers
operating with low temperature water, providing low flue gas
temperatures without the risk of condensation.
The surfaces of the dry ducts "A" feature cuts, to avoid dilation
issues.
The solid combustion residues (ashes), laid on the high tem-
perature refractory cradle will become, over time, increasingly
lighter until they are carried by the gas speed and deposited in
the lowest area of the rear smoke chamber, from which they will
be removed during cleaning.

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REFRACTORY BURNER (4)
The burner consists in a refractory stone (pos. 4.) This stone
has a central rectangular opening that the flame passes through.
The embers lie directly on the stone which divides the fire wood
storage compartment from the lower combustion chamber.
Furthermore the main refractory stone has a rectangular seat
in which the suitably grooved thermal steel fire bars are placed
(pos. 2), which receive the secondary air from a front distributor.
The embers are prevented from falling by refractory steel rings.
The combustion gases, poor in oxygen and still rich in carbon
not yet combined, go through the embers and enter the opening
in the centre of the main stone.
Inside this pre-combustion chamber, the gases combine with
the pre-heated secondary air coming through the grooves of
the two cast iron fire bars.
This will produce a high oxygen rich bluish-coloured flame.
This flame comes out from the oval opening and invades the
combustion chamber.
Due to the high temperatures at play the refractory burner will
turn a bright red colour.
COMBUSTION CHAMBER (5)
Combustion is optimised by increasing the flame temperature
and producing a strong turbulence in the bottom chamber.
For this reason the flame, in addition to not touching cold walls
irrigated by water, bounces and is divided on a semicircular
cradle which rests on the lower exchange surfaces, which, aside
from delimiting the smoke ducts, also has the task of collecting
the ashes and possible embers.
The flames, after bouncing off the walls of the lower area and
refractory parts, head with a whirling motion to the front part of
the combustion chamber and enter the flue ducts. Combustion
will be complete and clean and the dominant colour will be that
of the ashes: white.
M = Hot water flow
R = System return
P = Primary air
S = Secondary air
F = Flue gas
1. Refractory steel grate
2. Refractory steel fire bars
Technical features

14
2.6 - WOOD CHARACTERISTICS
Wood is formed mainly by cellulose and lignite. It
also contains other substances, such as resin (fir -
pine), tannin (oak - chestnut) and, obviously, a large
quantity of water.
Good quality woods are oak, ash, beech, maple and
fruit trees, except cherry; medium quality wood is:
chestnut and birch; sufficient quality wood: lime tree,
poplar and willow. Resinous trees are, normally,
second-rate quality fuels.
Wood is therefore an extremely heterogeneous
fuel, due to different essences (beech, oak, fruit,
resinous), different moisture content, and due to
different shapes and dimensions.
Boiler operation will inevitably be effected by all
these factors. Especially by the log dimensions, the
moisture content and the way wood is loaded in the
boiler.
WOOD MOISTURE
The calorific value of the different types of wood
depends on their moisture content, as illustrated in
the table. Boiler output and autonomy will diminish
as the moisture increases. The table provides the
power reduction factor based on the moisture of the
wood being used.The heat output of the NOVAIREX
boiler is calculated for wood with a 17% moisture
content.
As an example, wood which has been dried for
2 years in a sheltered area has a 25% moisture
content.
Example:
moisture of the wood being used = 25%
output = nominal output x 0.86
Correction factors for wood moisture
% OF
HUMIDITY
CALORIFIC
VALUE
kWh/kg
CORRECTION
FACTOR
15
20
25
4.50
4.18
3.87
1
0.93
0.86
DIMENSIONS
The dimensions, together with the moisture content,
contribute to determine the boiler’s output. Small
pieces (with a length, however, conforming to indi-
cations indicated hereby) are more easily flammable
and therefore have the tendency to increase the
boiler’s output and therefore to reduce its auton-
omy. Moreover, they fall with greater facility, in the
lower chamber, reducing the risk of the formation of
“bridges”. The so-called “bridge” is an empty space
in the firewood storage compartment, where unburnt
wood logs remain. In this case the bed of embers
is not fed with continuity and the refractory burner’s
slot is uncovered. In these conditions, preferential
air ducts are created with a very small flame due
to an excess of air.
CALORIFIC
VALUE
MJ/kg
16.20
15.05
13.93

15
Technical features and dimensions
3INSTRUCTIONS FOR
INSTALLATION
3.1 - GENERAL WARNINGS
ATTENTION!
This boiler is intended solely for the use for
which it was expressly designed. Any other
use is to be considered improper and there-
fore dangerous.
This boiler heats water at a temperature
lower than the atmospheric pressure boiling
temperature.
ATTENTION!
The appliances are designed to be installed
inside suitable rooms or technical spaces
only. The appliances cannot be installed or
operate outdoors. Outdoor installation can
cause malfunctioning and be dangerous.
Choose specifically designed appliances for
outdoor installation.
Before connecting the boiler, have professionally
qualified personnel:
a) Thoroughly wash all the piping of the system
to remove any residue or impurities which
could jeopardise proper operation of the
boiler;
b) Check that the chimney/flue has an appropri-
ate draught, without any bottlenecks, and that
no exhausts from other appliances are insert-
ed, unless the flue has been implemented to
accommodate several utilities according to
specific standards and prescriptions in force.
Only after this check can the fitting between
the boiler and chimney/flue be mounted;
ATTENTION!
The appliance must be installed by a qualified
technician with the technical-professional
requirements according to law 37/08 which,
under his own responsibility, guarantees
compliance with the standards according to
good practice rules.
The boiler must be connected to a central heat-
ing system and/or domestic hot water production
network compatible with its efficiency and output.
3.2 - INSTALLATION STANDARDS
It must be installed by a professionally qualified technician, who
shall take the responsibility of observing all local and/or
national laws published in the official journal, as well as
applicable technical standards.
3.3 - INSTALLATION ON
OLD OR RETROFITTABLE SYSTEMS
Before installing this appliance on old systems, check that:
- The flue is able to withstand the temperature generated by
the combustion products, has been measured and designed
according to the regulations in force, is airtight and insulated,
and does not feature obstructions or constrictions.
- The flue has a device for releasing condensation.
- The electrical system has been set up by a qualified techni-
cian in compliance with the rules in force.
- The rate, head and direction of the flow of the circulation
pumps are appropriate.
- The expansion vessel(s) can fully absorb dilation of the fluid
in the system.
- The expansion vessels can fully absorb dilation of the fluid
in the system.
- The system has been cleaned and cleared of all sludge and
scale, has been vented, and all its seals have been checked.
- There is a water supply treatment/recirculation system.

16
3.4 - PACKAGING
The NOVAIREX boiler is delivered unassembled: the casing, fan,
panel board, handles and cleaning accessories are shipped in
separate boxes.
After having removed all packaging, make sure that
the supply is complete and undamaged.
If in doubt, do not use the appliance and contact
the supplier.
The packaging elements (cardboard boxes,
straps, plastic bags, etc.) must be kept out of
the reach of children as they are potential
sources of danger.
Unical will not be held liable for damage to per-
sons, animals or objects due to failure to comply
with the instruction above.
3.5 - TRANSPORT
To make boiler transport, loading and unloading easier, it features
special "G" hooks on the top for lifting.
The document envelope, inserted in the wood storage compart-
ment, contains:
- Hydraulic test certificate (> 35 kW)
- User/System manager operating instructions for the system
- Installation and maintenance instruction booklet
- Warranty
- Coupons for returned spare parts
- Adhesive plate with technical data
- Adhesive plate with local ventilation requirements (< 35 kW)
If the boiler is stored for long periods, it should
be adequately protected.
Description of packs:
1. Boiler body
2. Package containing casing and boiler insulation
3. Package containing casing and smoke chamber insulation
4. Package containing the panel board
5. Package containing flue gas sucking fan
6. Package containing: air intake header, smoke chamber in-
spection covers, turbulators, handles, sundry screws, flame
inspection mirror, cleaning accessories. This package is sent
inside the wood storage compartment (top door).
6
1
2
G
54
3
5
1
2
G
4
3

17
Technical features and dimensions
600
1000
1300 600
600
3.6 - INSTALLATION
NOVAIREX is a heat generator which withdraws the combustion
air required for the combustion process directly from the room
in which it is installed.
For this reason, and above all for the safety of the persons using
NOVAIREX, it must be installed in a ventilated room so that a
continuous flow of combustion air is always assured.
It is therefore essential to make air vents linked with the outside
which, in compliance with that indicated by Standard UNI 10683,
have the following features:
1. A free width of 100 cm or more2, ensuring at least that pres-
sure in the installation area does not exceed 4 Pa;
2. Be made close to the floor;
3. Be appropriately protected by metallic mesh or grille so that
the minimum air passage cross-section is not reduced;
4. Be positioned in such a way that it cannot be obstructed.
The correct air influx can also be guaranteed by using
openings towards an adjacent room as long as that room
is provided with direct ventilation and that it is not a room
with a fire risk such as depots, garages or storerooms as
regulated by standard UNI 10683.
NOVAIREX should be installed in rooms without
natural draught equipment or appliances which
can create a vacuum in the room in relation to
the outside environment and therefore hinder
the draught of the flue gas exhaust system (UNI
10683).
To make it easier to clean, there must be a clearance space
in front of the heat stove no less than the length of the stove
itself. You must at least make sure that the door can open 90°
unobstructed.
NOVAIREX can be placed directly on the floor as it is equipped
with a self-supporting frame.
When inspecting compatibility of the heating
system, you should make sure that the support
surface (floor) has a support capacity (kg) suit-
able to bear the weight of the product. If it is not
adequate, suitable safety measures should be
taken (e.g. load distribution plate).
Furthermore, should the floor be made of combustible material
(such as parquet) it should be protected by placing a sheet of
fireproof material underneath the NOVAIREX and adequately
wider than the base.
When installation is complete, the boiler must be horizontal and
stable, in order to reduce vibrations and noise.
However clearance space must be left behind the boiler and on
both sides to allow the casing to be opened for maintenance.
There must also be sufficient clearance for loading the pellet tank.
Do not approach or touch the outer surfaces of the com-
bustion chamber with flammable material as it can reach
high temperatures following continuous use.

18
3.8 - HYDRAULIC CONNECTIONS
ATTENTION!
Before connecting the boiler to the heating
system, thoroughly clean the piping with an
appropriate product compliant with UNI-CTI
8065, in order to eliminate metallic residue
from processing and welding, oil and grease
which could be present and which, reaching
the boiler, could alter its functioning.
Attention!
The fittings of the boiler must not take the
weight of the connecting pipes of the sys-
tem; suitable supporting devices should be
installed to do this.
The dimensions of the supply and return pipes for each boiler
model are given in the DIMENSIONS table.
Check that the system is fitted with a sufficient number of vent
valves.
3.7 - CONNECTING BOILER
TO SYSTEM
Attention!
Make sure that there are no mechanical
tension points while connecting the pipes to
avoid the risk of leakage!
Heating flow and return pipes must be connected to the boiler
at the respective fittings as shown on page 6.
For the dimensioning of the heating circuit pipes, you must take
into account pressure drops caused by radiators, thermostatic
valves, radiator stopping valves and by the configuration of the
system.
The laying of the pipes must be designed taking every neces-
sary precaution to avoid air pockets and to facilitate continuous
degassing of the system.
Make sure that the pipes of the water and heating
system are not used as earthing electrodes of the
electric or telephone system.They are absolutely
not suitable for this type of use. Serious damage
could result for the piping, boiler and radiators in
a short amount of time.

19
Technical features and dimensions
6
SCARICO
1
2
ALIMENTAZIONE
3.8.1 - CONNECTION TO THE
SAFETY HEAT EXCHANGER
Solid fuel fired boilers must be installed with
the safety devices foreseen by the relevant
laws in force.
For this purpose NOVAIREX boilers are
equipped with a safety exchanger.
A temperature relief valve must be installed on the safety
heat exchanger by the installation technician, with control bulb
set up inside the suitable sheath located on the rear of the
NOVAIREX boiler.
Attention!
The input or output can be inverted as long as
the valve is installed on the cold water intake.
Provide a drain pipe with a funnel and a siphon
leading to an appropriate drainage at the heat exchanger outlet.
This drainage must be controlled on sight.
Attention!
If this precaution is not taken, triggering of
the thermal discharge valve can cause dam-
age to persons, animals and objects for which
the manufacturer cannot be held responsible.
POWER SUPPLY
DRAIN
DRAIN
DRAIN
POWER SUPPLY
POWER SUPPLY
CORRECT
INSTALLATION
INSTALLATION
WRONG

20
3.8.2 - RECIRCULATION PUMP
For correct generator operation, a recirculation pump must
be installed in the boiler.
The recirculation pump, supplied in an optional kit, must be
connected is indicated in the figure.
The recirculation pump must assure a return temperature
equal to or greater than 55°C.
It must be controlled exclusively from the boiler control
panel.
If it is not installed, besides limiting the boiler's lifespan, it
will invalidate the warranty.
ATTENTION!
The hardness of the mains water supply con-
ditions the boiler's lifespan.
It is always recommended to treat water with a
hardness greater than 15°f.
Unical has designed a "RECIRCULATION KIT FOR OPERATION
WITH STORAGE TANK" for its customers.
The kit is supplied as an option and is available by indicating
the model of your boiler.
3.8.3 - ASSEMBLY INSTRUCTIONS
Fan assembly
Fit the fan to the smoke chamber.
IMPORTANT!
When the fan is being installed
the smoke chamber gasket must be
perfectly sealed, otherwise the wall of the
gasket would deform, causing serious
damage to the impeller and/or fan motor.
This issue occurs even more quickly the more
the wood loading door is opened.