RED TECNIKA 28 Technical specifications

USE AND INSTALLATION
MANUAL
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EN
COD.8901113900

Contents Technical dept. - All rights reserved - Reproduction prohibited
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1.GENERAL INFORMATION .....................................................................................................3
1.1.Symbols used in this manual ...................................................................................................3
1.2.Proper appliance use...............................................................................................................3
2.GUARANTEE TERMS..............................................................................................................5
2.1.Warnings ...............................................................................................................................5
The guarantee applies, provided that:..................................................................................................5
2.2.Exclusions..............................................................................................................................5
2.3.Additional clauses ...................................................................................................................6
2.4.Liability..................................................................................................................................6
2.5.Court with jurisdiction .............................................................................................................6
2.6.Liability exclusion....................................................................................................................6
2.7.Service call.............................................................................................................................7
2.8.Installation standards..............................................................................................................7
3.TECHNICAL SPECIFICATIONS AND DIMENSIONS ...............................................................8
3.1.General information on hot water boilers ..................................................................................8
3.2.TECNIKA 28-35 boiler description.............................................................................................8
3.3.Technical data........................................................................................................................9
3.4.Boiler fuel supply..................................................................................................................11
3.5.Main components .................................................................................................................12
4.INSTALLING A "TECNIKA" HOT WATER BOILER................................................................16
4.1.Packaging ............................................................................................................................16
4.2.Boiler room ..........................................................................................................................16
4.3.Connection to the flue pipe....................................................................................................17
4.3.1Roof outlet along an external steel flue pipe........................................................................19
5.3.1Roof outlet along a traditional flue pipe...............................................................................20
4.4.System connection................................................................................................................21
4.5.Filling the system..................................................................................................................21
4.6.Basic requirements for installing “Tecnika” hot water gasification boiler to allow simple
maintenance and servicing:...............................................................................................................22
5.OPERATION ........................................................................................................................29
5.1.“Tecnika” hot water wood gasification boiler interface control panel..........................................29
6.START-UP PROCEDURES ....................................................................................................31
6.1.Basic requirements ...............................................................................................................31
6.2.Electrical connections............................................................................................................32
6.3.1Wiring diagram .................................................................................................................33
6.3.Boiler start-up preparation procedure .....................................................................................34
6.4.Igniting the fuel and heating the boiler...................................................................................34
6.5.Adjusting the air flow control thermal valve ............................................................................36
6.6.Nominal operating mode of the boiler.....................................................................................37
6.7.Fuel hopper loading ..............................................................................................................38
6.8.Adjusting boiler operating parameters ....................................................................................40
6.9.Boiler operation in stand-by mode..........................................................................................43
6.10.Boiler shutdown ...................................................................................................................43
7.TROUBLESHOOTING...........................................................................................................45
8.CLEANING AND MAINTENANCE .........................................................................................47
8.1.Instructions for inspection and maintenance ...........................................................................47
8.2.Training and end user demonstration of maintenance and adjustment procedures of the boiler...53

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General information Technical dept. - All rights reserved - Reproduction prohibited
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General information
The user is NOT permitted to service this boiler.
The manufacturer cannot be held liable for personal injury, harm to animals or property damage resulting
from failure to observe the instructions contained in the manuals supplied with the boiler.
1. GENERAL INFORMATION
1.1. Symbols used in this manual
When reading this manual, pay particular attention to the parts marked with symbols. These symbols are
used to give the following warnings:
1.2. Proper appliance use
The instruction manual is an integral and essential part of the product and must be kept by the user or
system manager.
Read the warnings contained in the manual carefully, since they provide important information about safe
installation, use and maintenance.
Keep the manual in a safe place for future reference.
Installation and maintenance must be performed in compliance with the applicable regulations according to
the manufacturer's instructions and by qualified personnel trained pursuant to the law.
Incorrect installation or improper maintenance could cause personal injuries, harm to animals or property
damage, for which the manufacturer will not be held liable.
Before carrying out any cleaning or maintenance operations, disconnect the appliance from the mains power
supply using the system switch and/or the relevant cut-off components and close all cocks.
If the appliance has a fault and/or is not operating correctly, switch the appliance off and do not make any
attempt to repair it or service it directly. Contact authorised personnel only. Any repairs to products must be
carried out using only original spare parts. Failure to observe the above recommendations may compromise
the safety of the appliance.
If the appliance is sold or transferred to a new owner or the owner moves, leaving the appliance in situ,
always ensure that the manual is kept with the appliance so that it can be consulted by the new owner
and/or installer.
For all appliances with optional equipmement or kits (including electrical kits) use only original accessories.
This appliance must be used only for the use expressly intended. Any other use is to be considered incorrect
and therefore dangerous.
DANGER!
Serious risk to safety
and to life
CAUTION!
Potentially hazardous
situation for the product and
the environment
NOTE!
Recommendations for
users

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General information Technical dept. - All rights reserved - Reproduction prohibited
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The TECNIKA appliance has been built according to the latest technologies and in
accordance with the applicable technical safety regulations.
Nonetheless, the incorrect use of the appliance may result in hazards and also endanger the
user or others, or even damage the appliance or other objects.
The appliance is intended for the operation of hot water heating systems.
Appliance use in accordance with the envisaged purposes includes scrupulous observance of
the instructions provided in this manual.
RED reserves the ri
g
ht to make any chan
g
es to the desi
g
n and factory settin
g
s of the burner and hot water
boiler without having to inform the end users of such changes.
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Guarantee term Technical dept. - All rights reserved - Reproduction prohibited
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2. GUARANTEE TERMS
The Manufacturer guarantees the product, with the exception of parts subject to normal wear specified
below, for two years from the date of purchase, provided that proof of purchase is supplied in a document
specifying the name of the retailer and the date the sale was made and that the completed guarantee
certificate was sent within 8 days of said purchase. The product must also be installed and tested by a
specialised installer and in accordance with the detailed instructions provided in the instruction manual that
accompanies the product.
The guarantee covers the replacement or free repair of parts recognised as being faulty at source due to
manufacturing defects.
2.1. Warnings
Installation, electrical connection, functional check and maintenance of this appliance must only be
performed by qualified or authorised personnel.
This appliance must not be used by anyone (including children) with reduced physical, sensory or
mental skills and with little experience and knowledge, unless they are supervised or have been
instructed to use the appliance by the person in charge of its safety.
The guarantee applies, provided that:
1. The boiler is installed, in accordance with the applicable standards in force and the instructions
provided in the product use, maintenance and installation manual, by legally qualified personnel
(Italian Ministerial Decree no. 37 of 22nd January 2008);
2. The customer holds the documentation certifying its suitability in all parts:
a. INSTALLATION REPORT - filled in by the installer
b. TEST REPORT and GUARANTEE APPLICATION - filled in by an authorised serviceman
c. The guarantee applies from the date of first start-up of the boiler, which must be
indicated on the boiler manual or from the invoice date. This documentation must be
presented to the authorised service centre in the event of servicing.
2.2. Exclusions
The guarantee does not cover any parts found to be faulty due to negligence or inappropriate use, incorrect
maintenance, or installation not performed in compliance with the manufacturer's instructions. The
manufacturer will not be held liable for any damage which may - either directly or indirectly - be caused to
persons, animals or property resulting from failure to observe all the instructions provided in this manual
and, specifically, concerning the warnings regarding installation, use and maintenance of the appliance.
The guarantee is not valid if:
1. The terms for the guarantee application were not observed.
2. Installation was not performed in observance of the applicable standards in force and the
instructions provided in the use, maintenance and installation manual.

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The guarantee does not cover:
1. Damage made by atmospheric agents, chemicals, electrochemical elements, incorrect product use,
natural disasters, electrical discharges, fires, faults in the electrical system, modifications to or
tampering with the product, and/or other causes not ensuing from the product manufacturing
2. Damage caused by normal corrosion
3. Damage relating to the combustion chamber
4. Damage to seals, claddings, painted/chromed parts, handles and electrical wires
5. Damage to masonry work
6. Damage to parts of the system for the production of DHW not supplied by RED
7. Damage to the heat exchanger if a suitable condensation-proof circuit is not set up to guarantee a
minimum boiler return temperature of at least 55 °C.
8. Servicing for calibration or product adjustments
9. Incorrect or negligent use.
10. All damage caused by transport; we consequently advise you to check the goods carefully upon
receipt, notifying your retailer immediately of any damage, making a note on the delivery note and
on the copy that travels with the carrier.
Please contact your retailer and/ or local importer in the event of product failure.
RED will not be held liable for any damage which may - either directly or indirectly - be caused to property,
or personal injury or harm to animals ensuing from failure to observe all the instructions provided herein and
the applicable regulations regarding installation, use and maintenance of the appliance.
The parts replaced will be guaranteed for the remaining guarantee cover period starting from the original
date of purchase of the product.
2.3. Additional clauses
If faulty or malfunctioning parts are detected during normal product use, these will be replaced free of
charge ex retailer who made the sale or ex our local technical service centre.
For products sold abroad, the same circumstances will again result in free replacement, ex our retailer, with
the exception of specific conditions agreed upon at the time of negotiations with the foreign distributor.
In the case of replaced parts, the guarantee will not be extended.
No damages are awarded for the product downtime period.
This is the only applicable guarantee and no-one is authorised to provide any other guarantees in the name
of or on behalf of RED.
2.4. Liability
RED will not pay any compensation for direct or indirect damage caused by or dependent upon the product.
2.5. Court with jurisdiction
In the event of any controversy, the court with jurisdiction is the Court of Pordenone (Italy).
2.6. Liability exclusion
The manufacturer is not able to supervise the observance of the instructions provided in this manual. Nor is
it able to monitor the conditions and methods of installation, operation, use and maintenance of the product.
Incorrect installation could cause damage and endanger persons. Consequently, we cannot be held in any

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way liable for losses, damage or costs ensuing from incorrect installation, improper functioning and incorrect
use and maintenance or in any way connected to the latter. Similarly, we will not be held in any way liable
for any violations of patents or third party rights ascribable to the use of this product.
The manufacturer reserves the right to make any changes to the product, technical specifications or to the
manual without notice.
If hazard-free operation is no longer possible (for instance, due to visible damage), turn off the appliance
immediately.
2.7. Service call
Service calls must be made to the retailer, who will forward the call to the technical support department.
The manufacturer cannot be held liable if the product and any of its accessories are used incorrectly or
modified without authorisation.
Only original spare parts must be used for replacements.
2.8. Installation standards
Tecnika 28-35 is wood-fired boiler.
It must be installed according to the provisions of the following standards:
Italian Law Decree no. 93 of 25th February 2000
Implementation of Directive 97/23/EC (P.E.D.) on the subject of pressure equipment.
SCOPE OF APPLICATION: liquid fuel (naphtha, gas oil, fuel oil) and solid fuel operated appliances.
ITALIAN LAW no. 46 of 5th March 1990 and related applicative regulations Italian Ministerial Decree no.
447 of 6th December 1991 (and subsequent amendments)
System safety standards
SCOPE OF APPLICATION: without limits to heat potential.
Standard UNI 10847 of 03/2000
Single flue systems for liquid and solid fuel generators. Maintenance and control. Guidelines and procedures.
SCOPE OF APPLICATION: liquid and solid fuel operated systems.
ITALIAN LAW of 9th January 1991 No. 10 and related applicative regulations Italian Ministerial Decree
no. 412 of 26th August 1993 (and subsequent amendments), Italian Ministerial Decree no. 551 of 21st
December 1999.
Regulations specifying amendments to Italian Presidential Decree 412 on the subject of planning, installing,
running and servicing heating systems in buildings for the purposes of limiting energy consumption.
SCOPE OF APPLICATION: without limits to heat potential.
ITALIAN LAW NO. 186 of 01.03.1968
Installation standard CEI 64-8 / II ed.
Electrical utility systems at a nominal voltage of no more than 1000 V in alternating current and 1500 V in
direct current.
Installation standard CEI 64-8 / I ed.
Electrical utility systems in buildings intended for residential and similar purposes.

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3. TECHNICAL SPECIFICATIONS AND DIMENSIONS
3.1. General information on hot water boilers
"TECNIKA" hot water wood gasification boilers are have a steel structure and use solid biomass, in the form
of wood logs, as fuel. The boiler is designed for connection to hot water heating systems.
Tecnika boilers comply with P.E.D. 97/23/EC.
TECNIKA series hot water wood gasification boilers consist of the following components:
"TECNIKA" hot water boiler - 1 (one)
ceramic ducting element in combustion chamber - 1 (one)
thermal valve for controlling air flow rate - 1 (one)
steel brush for cleaning ashes - 1 (one)
ash scraper – 1 (one)
"TECNIKA" series hot water boiler use and instruction manual - 1 (one).
3.2. TECNIKA 28-35 boiler description
The "TECNIKA" hot water boiler heat exchanger complies with the operating requirements of this type of
appliance, as set out in the operation standard:
EN 303-5/2000.
The hot water boiler consists of the following components/modules:
heat exchanger, consisting of a welded steel plate structure. The upper part of the boiler
accommodates the fuel hopper which is manually filled with wood logs. The fuel chamber is the ideal
environment for the fuel pyrolysis process and volatile gases are conveyed towards the lower section
of the boiler, where they are oxidised in the combustion chamber. The combustion chamber contains
a ceramic coating, a nozzle and a combustion gas ducting element to ensure combustion process
efficiency;
combustion nozzle, made of ceramic material, positioned in the lower section of the fuel hopper
to ensure optimal conditions for combustion process efficiency;
ceramic ducting element,positioned in the boiler combustion chamber allows high temperature
levels and guarantees optimal fuel oxidation;
combustion gas fan fitted on the back of the boiler conveys combustion gases outside the boiler
and controls its operation;
air distribution box, provided with primary air control valve. This box doubles as heat exchanger
and pre-heats the ambient air before it is used in the combustion chamber of the boiler. The inlet of
this box is provided with an inlet control fin actuated by a thermostat valve and controls the air
taking into the boiler;

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hydraulic connections, have female threading (see table for dimensions) and are positioned in
the lower rear left part of the heat exchanger along the return line and in the upper rear left part of
the boiler along the flow line;
exhaust connection has female threading (see table for dimensions) and must be connected to
the exhaust valve;
emergency cooling coil is used for emergency cooling of the water circulating the heat exchanger
of the boiler when the water is very hot. The coil has a G½” male union threading;
combustion gas outlet duct (external diameter shown in Table 2.2) is located in the upper rear
part of the boiler;
the heat exchanger is thermally insulated with mineral wool to minimise thermal dispersion;
doors of the fuel hopper and the combustion chamber are made of cast iron to ensure high thermal
resistance and sealing of the boiler;
external casing of the boiler is made with sheet steel.
3.3. Technical data
Thermal and technical data of “TECNIKA” hot water wood gasification boilers:
PARAMETERS UNIT OF
MEASURE VALUES
MODEL 28 35
HEAT OUTPUT AT COMBUSTION CHAMBER kW 28 35
NOMINAL HEAT OUTPUT kW 25 30
OPERATING RANGE (min-max) kW 13-25 15-30
SOLID FUEL USED Wood logs for heating, max. water content 20%
WOOD LOG CONSUMPTION RATE (min-max) kg/h 3,7-6,9 5,1-9,7
FRESH AIR RATE REQUIRED FOR EFFICIENT
COMBUSTION PROCESS AND BOILER
OPERATION
kg/h 80-95 110-130
m3/h 55-70 100-110
AVERAGE WOOD LOG CONSUMPTION RATE
(the boiler operates in a normal heating
system)
kg/h 4.7 6.7
HEATING EFFICIENCY (min-max) % 85
TEMPERATURE OF COMBUSTION GASES AT
NOMINAL HEAT OUTPUT
°C 180-230
SOLID FUEL RESIDUE ASH The quantity depends on the ash contents of
the raw fuel, as well as on the operating
conditions
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Dimensions and technical data of “TECNIKA” hot water wood gasification boilers:
PARAMETERS UNIT OF MEASURE
V
ALUES
MODEL 28 35
WEIGHT kg 290 370
WATER SLEEVE CAPACITY dm370 90
FUEL CHAMBER CAPACITY
dm3100 130
kg 16-20 20-24
NOMINAL HEAT OUTPUT TIME INTERVAL AFTER LOADING
FUEL CHAMBER Hours 2-3 2-3
MAXIMUM WOOD LOG LENGTH mm 330 500
DIMENSIONS
L=WIDTH
mm
780
P=DEPTH 975 1123
A=HEIGHT 1282
OPERATING PRESSURE OF CIRCULATING WATER bar 2
HYDRAULIC PRESSURE LOSS AT NOMINAL HEAT OUTPUT Pa 20 21
TYPE OF EXPANSION VESSEL FOR THE HEATING SYSTEM - Open or closed
PRESSURE TESTED IN THE FACTORY bar 4
RECOMMENDED TEMPERATURE FOR THE WATER
CIRCULATING IN THE BOILER °C 80-85
RECOMMENDED TEMPERATURE FOR RETURN WATER IN THE
BOILER °C 60
DRAUGHT hPa 0.18-0.24
CONNECTIONS
FLOW/RETURN G 1 ½”
EXHAUST G ¾”
EMERGENCY COOLING COIL G ½”
COMBUSTION GAS DUCT mm 150
POWER SUPPLY - 230 V; 50 Hz
POWER SUPPLY CABLE - 3 x 1.5 mm2
ELECTRICAL CAPACITY VA 37 65
ELECTRICAL PROTECTION - IP20
BOILER CLASS (ACCORDING TO EN 303-5) - 3
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3.4. Boiler fuel supply
The boiler must be supplied with the following fuel:
wood logs, preferably cut, with the following features:
opure wood, use of contaminated wood is not allowed (i.e. painted wood, subjected to
chemical treatment or other mineral or organic substances)
othe length of the wood logs must correspond to the depth of the combustion chamber of the
boiler
(see boiler technical specifications)
othe crosswise section (diameter) of the wood logs must be: D ≤200 mm
othe raw material humidity content must be less than 20% (Wr≤20%)
owood-based fuel such as sawdust, wood chips and other small combustible particles may be
used in addition to wood logs, but their total amount must be less than 20% of the fuel
loaded into the boiler chamber.
Approximate recommended fuel parameters - cut, pre-dried wood logs
PARAMETERS UNIT OF MEASURE VALUES
TYPE OF FUEL WOOD LOGS
WOOD LOG LENGTH mm See previous table
HUMIDITY CONTENT % ≤20%
CALORIFIC POWER OF FUEL
USED IN OUR CALCULATIONS
MJ/kg >13.9
kWh/kg >3.9
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EXPLANATION: the maximum percentage of humidity in wood must be 20%. It is advisable to use wood
dried for at least 1 year.
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3.5. Main components
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Fig. 3.5.1 View of the “TECNIKA” hot water wood gasification boiler - Description of main
components of the boiler
COMBUSTION
CHAMBERDOOR
FUELHOPPERDOOR
BOILERCONTROLPANEL
AIRFLOWCONTROL
THERMALVALVE

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G 1 ½”
G 1 ½”
G ½”
G¾”
EXPLANATION: the values of the dimensions indicated by letters: L, A and P are shown in Table page 12.
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Fig.3.5.3 Side view of the “TECNIKA” hot water
wood gasification boiler
Fig.3.5.2 Front view of the “TECNIKA” hot water
wood gasification boiler
Fig.3.5.4 Rear view of the “TECNIKA” hot water wood
gasification boiler
Fig.3.5.5 Top view of the “TECNIKA” hot water
wood gasification boiler
P

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Combustion gas outlet (conveyed to
convective ducting of the boiler)
Ceramic combustion gas ducting element
in combustion chamber
Combustion chamber
Combustion nozzle
Fuel hopper
Opening for extracting gas from
combustion chamber for start-up
Primary air inlet opening
Fi
g
.3.5.6 Section view of the “TECNIKA” hot water wood
g
asification boiler

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The manufacturer reserves the right to make any changes to design and construction of the
boiler without having to inform end users of such changes.
Boiler control box
Upper lid of boiler convective ducting
Combustion gas fan
Combustion gas outlet ducting
Combustion nozzle
Ceramic coated combustion
gas ducting element
Lower lid of boiler convective
ducting
Fi
g
.3.5.7 Lon
g
itudinal view of the “TECNIKA” hot water wood
g
asification boiler

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Installing Technical dept. - All rights reserved - Reproduction prohibited
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4. Installing a "TECNIKA" hot water boiler
CAUTION: be careful not to damage or crack the ceramic element fitted inside the combustion chamber of
the boiler when transporting the boiler (secure the element appropriately or transport it separately from the
boiler):
installing the hot water boiler in rooms not fit for occupancy, including corridors, is not allowed
the "TECNIKA" wood gasification boiler may be connected to a heating system equipped with open
or closed expansion vessel designed according to the water capacity of the entire heating system
both the heating system and the hot water boiler must be filled with circulating fluid (water) and air
must be bled from the system before starting up the boiler.
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4.1. Packaging
The boiler is delivered complete with assembled electrical and mechanical parts after having been tested at
the factory.
The boiler is delivered on one pallet. The boiler must always be handled vertically, using manual or
mechanical cranes, which can lift the pallet on which it is packaged or the boiler itself directly.
Take special care not to damage electrical or mechanical parts, with shocks or water sprays once the
protective packaging has been removed.
After removing the packaging, make sure the boiler is complete and undamaged
If in doubt, contact the retailer
The document envelope contains:
System manual
An instruction manual for installation, use and maintenance
Appendix G - Technical inspection report for heating system with an output of less than 35 kW
Guarantee
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4.2. Boiler room
Make sure the room complies with the requirements and characteristics set out in the applicable regulations
in force. It is also necessary for the room to provide at least as much air as is required for regular
combustion. It is therefore necessary to make holes in the walls of the room, which comply with the
following requirements:
Have a free cross-section of at least 6 cm2 for every 1 kW (859.64 kcal/h). Nevertheless, the
minimum cross-section of the opening must never be less than 100 cm2. The cross-section can also
be calculated using the following ratios:
S = K * Q ≥100 cm2
Where “S” is expressed in cm2, “Q” in kW, “K” = 6 cm2/kW
The opening must be situated at the bottom of an external wall, preferably opposite the one where
the combustion gases are vented.

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4.3. Connection to the flue pipe
For the connection of the flue outlet pipe, local and national regulations must be observed (see Standards
UNI 7129 and UNI 10683).
A flue pipe must comply with the following requirements:
It must be made of waterproof material resistant to the temperature of the smoke and related
condensation.
It must ensure sufficient mechanical resistance and weak heat conductivity.
It must be perfectly sealed, to avoid the cooling of the flue pipe itself.
It must be arranged as vertically as possible.
Chimneys both old and new, built without observing the above specifications, may be conveniently
recovered by "intubating" the chimney itself. This means a metal flue shall be inserted inside the
existing chimney and the space between the metal flue and the chimney shall be filled with suitable
insulation.
In order to prevent the wind from creating pressure areas around the chimney that prevail over the
rising force of the combustion gases, the outlet aperture must be positioned at least 0.4 metres
above any structure adjacent to the chimney itself (including the ridge of the roof) at least 8 metres
away.
The flue pipe must have a diameter of no less than the boiler union; for flue pipes with a square or
rectangular cross-section, the internal cross-section must be increased by 10% compared to the
boiler union.
The useful cross-section of the flue pipe can be calculated using the following formula:
S= K x P/√H
Sensuing section in cm2
Kreduction coefficient:0.045 for wood
Pboiler output in kcal/h
Hheight of the chimney in metres, measured from the flame axis to the outlet of the chimney into
the atmosphere. When sizing the flue pipe, please take into account the actual height of the
chimney in metres, measured from the flame axis t the top, decreased by:
0.50 m for every change in direction of the union duct between the boiler and the flue pipe
1.00 m for every metre of horizontal development of the union itself.
We recommend the sole use of outlet ducts which are suitable for the
type of fuel used. The supplier will not be held in any contractual and
non-contractual way liable for damage caused by installation and
usage errors and in any case due to failure to observe the instructions
provided by the manufacturer of the appliance.
The products of combustion of the boiler cannot be discharged in
collective flue ducts.
The correct installation of the flue duct is necessary to encourage the
normal flow of smoke from the combustion chamber to the outside in
the event of an electrical power failure.
Remember that a draught of 20 Pa must be guaranteed.

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Below are the main characteristic traits of the flue duct according to the provisions of
standards UNI 7129 and UNI 10683:
The smoke outlet must be equipped with inspection valves;
The minimum height of the pipe directly connected to the smoke outlet of the boiler must be
between 2-3 m;
If the presence of a horizontal section is necessary, we recommend that the same is of a maximum
length of 1.5 m and with a slope gradient of 3-5% to encourage the smoke to flow away;
Use of a wind-proof and rain-proof terminal to avoid changing the slight overpressure inside
the flue pipe (we recommend you end the flue pipe with a horizontal section);
The outlet ducting must be made with suitable materials which can withstand the products of
combustion and any condensation of the same (the inspection valve can allow any condensation
that has formed to be vented);
The ducts must be built to ensure maximum seal against smoke (UNI 10683);
We recommend you insulate the duct, especially on the outside part exposed to the weather.
Avoid installing completely horizontal sections.
The room where the heat generator is to be installed must not contain any existing or
envisaged smoke suction hoods in order to avoid depressurising the setting.
The air intakes must not be closed.
Make sure the flue pipe is kept clean, cleaning it at least once a year.
In the event of a fire in the flue pipe or duct, switch the boiler off
immediately and disconnect it from the domestic electricity mains

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4.3.1 Roof outlet along an external steel flue pipe
One of the installation solutions which could be used is to position the boiler near a perimeter wall of the
home (see figure below) so that the smoke is discharged along an external flue pipe. Here are some of the
provisions of standard UNI 7129 for this particular system configuration:
- Always make sure there is an inspection valve to allow periodic and efficient cleaning, as well as the
venting of any condensation that may have formed;
- The chimney must under all circumstances be wind-proof and rain-proof;
- Make sure the smoke outlet duct is suitably insulated in the section that crosses the wall.

It is advisable for the smoke outlet duct, if it is completely outside, to be made of double-wall stainless steel
to guarantee both greater resistance to the atmospheric agents as well as the appropriate temperature of
the smoke outlet.
Chimney
Insulatethe
fluepipe
Soottray

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5.3.1 Roof outlet along a traditional flue pipe
The flue smoke can also be discharged using an existing traditional flue pipe provided it is compliant to
standards (see UNI 10683).
Here is a brief list of the main characteristics highlighted in the standard that distinguish a good chimney:
- Suitable insulation and lagging especially in the external section exposed to the atmosphere;
- Constant internal cross-section (there must not be any narrower sections);
- Made with material resistant to high temperatures, to the action of the products of combustion and to the
corrosive action of any condensation that may form;
- Prevalently vertical arrangement with deviations from the axis of no more than 45°;
It is compulsory to plan a chamber for the collection of solid material and/or any condensation, which can be
inspected through an airtight door.
It is compulsory for you to observe the provisions of standards UNI 9615 and 9731 for the sizing of the
chimney cross-section and in any case that you avoid installing ducts with a cross-section of less than
150 mm.
In the case of larger cross-sections, it may be necessary to insert a steel duct inside the masonry one.
Direct wall discharge is not permitted.
The steel pipe must be suitably insulated with material which is resistant
to high temperatures and sealed off from the external chimney.
Soot tray accessible for
inspection with possible
condensation discharge