DOMUSA TEKNIK LIGNUM NG Series User manual

INSTALLATION AND OPERATING INSTRUCTIONS
LIGNUM NG

Thank you for choosing a DOMUSA TEKNIKheatingboiler.Fromtherange
of DOMUSA TEKNIK products you have chosen the Lignum NG model.
With a suitable hydraulic installation and with firewood for fuel, this high-
efficiency wood boiler will provide the ideal level of comfort for your
home.
This manual forms an essential part ofthe product and it must be given to
the user. We recommend you read the warnings and recommendations in
the manual carefully, as they contain important information on the safety,
use and maintenance of the installation.
These boilers must be installed by qualified personnel only, in accordance
withthelegislationinforceandfollowingthemanufacturer'sinstructions.
Incorrect installation of these boilers could result in damage to people,
animals or property, and the manufacturer will hold no liability in such
cases.

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CONTENTS Page
1LISTOFCOMPONENTS.....................................................................................................................................................2
2CONTROLCOMPONENTS................................................................................................................................................3
3INSTALLATIONINSTRUCTIONS.....................................................................................................................................4
3.1LOCATION.............................................................................................................................................................................................4
3.2HYDRAULIC INSTALLATION..................................................................................................................................................................4
3.3FUEL:PREPARING THE FIREWOOD.......................................................................................................................................................5
3.4IGNITION AND POSITIONING OF THE FIREWOOD ................................................................................................................................7
3.4.1IGNITION TUNNEL..............................................................................................................................................................................7
3.4.2PAPER,CARDBOARD AND KINDLING................................................................................................................................................7
3.4.3SAWN WOOD (PLANKS)....................................................................................................................................................................8
3.4.4THICK WOOD OR STUMPS.................................................................................................................................................................8
3.4.5THICK KINDLING AND WOODWORKING WASTE...............................................................................................................................8
3.5UNSUITABLE FUEL ................................................................................................................................................................................8
3.6COMBUSTION PRODUCT REMOVAL.....................................................................................................................................................8
3.7ELECTRICAL CONNECTION...................................................................................................................................................................9
3.7.1DHWTANK ELECTRICAL CONNECTION (OPTIONAL)......................................................................................................................9
3.8EXAMPLE OF AN INSTALLATION WITH A BUFFER TANK....................................................................................................................10
3.9EXAMPLE OF AN INSTALLATION WITH A BUFFER TANK AND DHWTANK.......................................................................................11
4ADJUSTINGTHECOMBUSTION AIR..........................................................................................................................12
5 TEMPERATURE RELIEF SAFETYVALVE.....................................................................................................................13
5.1OPERATING PRINCIPLE .......................................................................................................................................................................13
5.2VALVE ASSEMBLY................................................................................................................................................................................13
6 STARTING UP THEBOILER............................................................................................................................................14
6.1PRIOR WARNINGS ...............................................................................................................................................................................14
6.2FILLING THE INSTALLATION................................................................................................................................................................14
6.3START-UP............................................................................................................................................................................................14
6.4INSTALLATION HAND OVER................................................................................................................................................................15
7DIGITALDISPLAY AND SELECTING PARAMETERS............................................................................................... 16
8BOILERMAINTENANCE AND CLEANING................................................................................................................. 18
8.1CLEANING THE BOILER .......................................................................................................................................................................18
8.1.1ASHES..............................................................................................................................................................................................18
8.1.2TAR...................................................................................................................................................................................................18
8.2BOILER MAINTENANCE:......................................................................................................................................................................19
8.2.1DRAINING THE CONDENSATION WATER........................................................................................................................................19
8.2.2BOILER WATER CHARACTERISTICS..................................................................................................................................................19
8.3SAFETY WARNINGS:............................................................................................................................................................................20
8.3.1SAFE HANDLING OF ASHES.............................................................................................................................................................20
8.3.2HAZARDS RELATED TO THE DOOR OF THE FUEL LOADING CHAMBER.........................................................................................20
9 SHUTTING DOWN THEBOILER...................................................................................................................................21
9.1DETECTION OF LACK OF FUEL............................................................................................................................................................21
10TECHNICALCHARACTERISTICS................................................................................................................................ 22
11DIAGRAMSANDMEASUREMENTS.........................................................................................................................23
12ELECTRICAL DIAGRAM................................................................................................................................................ 24
13SENSORVALUES............................................................................................................................................................25
14SPARESLIST....................................................................................................................................................................26
15ALARMCODES...............................................................................................................................................................38
16GUARANTEECONDITIONS........................................................................................................................................39

Lignum NG
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1LIST OF COMPONENTS
1.Waterinlet/outlet
2.Topcover
3.Safetyheatexchanger
4.Pipecleaningmechanism
5.Fumepipes
6.Toprefractoryelement
7. Bottom refractory element
8. Controlpanel
9. Heatexchanger
10. Woodhousing
11. Peep-hole
12. Base
13. Topdoor
14. Bottomdoor
15. Extractor fan
16. Fume chamber

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2CONTROLCOMPONENTS
1.ButtonforchangingMenusettings:
Usedfor selecting the adjustable Menu settings.
2.STOPbutton(andreducevalue):
Used to stop the fan and, as a result, the
combustion adjustment. Also used to reduce
thevaluesoftheselectedMenusettings.
3.STARTbutton(andincreasevalue):
Activates the fan and the combustion
adjustment. Also used to increase the values of
the selected Menu settings.
4.Mainswitch:
Turnonthecontroller.
5.Fusecarrier:
It protects the controller and the elements
dependent on the controller. It is recommended
that a porcelain, slow-blow, 5x20mm, 3.15A
nominal current fuse be used.

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3INSTALLATIONINSTRUCTIONS
The boiler must be installed by personnel authorised by the Ministry of Industry, in compliance with
theapplicablelawsandregulations.
This boiler is suitable for heating water to a temperature below boiling point at atmospheric pressure.
It must be connected to a heating buffer tank, which must always be compatible with its performance
andpower.
This appliance must only be used for the purpose for which it has been expressly designed. Any other
use is considered unsuitable and therefore hazardous. The manufacturer shall not be considered liable
under any circumstancesfor damage caused by unsuitable,erroneousorirrationaluse.
Remove all the packaging and check the contents are complete. In case of doubt, do not use the
boiler. Contact your supplier. Keep the packaging elements out of reach of children, as they can be
dangerous.
When younolonger wish to usethe boiler, disable thepartsthatcouldrepresent a potential hazard.
3.1 Location
The boiler must be installed in a sufficiently ventilated site, away from humidity. It must be located
so that the air grilles on the premises are not obstructed and normal boiler maintenance is possible.
It must be kept a minimum distance of 1 m from the fuel tank or install a radiation protection plate.
The boilers must not operate on flammable surfaces. The boiler must have an external combustion
airsupply(minimumopening300 cm2).
Generally, it is not recommended to install boilers of up to 50 kW in stairways, living areas, corridors
or garages. Similarly, installing boilers in locations with ventilation, fans, extractor fans, air
extraction systems, etc. should be avoided (e.g. tumble dryer extraction). It must be kept a
minimum distance of 0.4 m from flammable building materials so as to not reach surfaces
temperaturesabove85°C.
3.2 Hydraulic installation
The hydraulic installation must be made by qualified personnel. The applicable installation
legislation (RITE) must be complied with, and the following recommendations should also be taken
intoaccount:
- It is obligatory and essential to install a heating water buffer tank (see “ Example of
installation with buffer tank ” ). The minimum volume of the buffer tank must be calculated
basedonStandardEN303-5.
- It is obligatory and essential to install a device for raising the return temperature, to prevent
any water condensation in the heat exchanger. If this requirement is not complied with,
DOMUSATEKNIK's guarantee of the appliance will automatically be null andvoid.
- It is obligatory and essential to install the temperature relief valve supplied with the boiler.
To correctly install the boiler, carefully follow the instructions given in the section "Installing
the temperature relief valve" . If this requirement is not complied with, DOMUSA TEKNIK's
guaranteeoftheappliancewillautomaticallybenullandvoid.
- The inside of the installation piping should be thoroughly cleaned before switching on the
boiler.
- We recommend inserting cut-off valves between the installation piping and the boiler to
simplifymaintenancetasks.

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- Leaveafreespacearoundtheboilerforcarryingoutanymaintenanceandrepairoperations.
- Drainvalvesandsuitabledevices forcorrectly bleeding the air fromthecircuitduringtheboiler
fillingstageshouldbefitted.
- Install all the necessary safety elements (expansion vessel, safety valve, etc.) to comply with the
applicableregulationsfortheinstallation.
3.3 Fuel:preparing the firewood
Firewood is the fuel which must be used for the Lignum NG boiler. If this requirement is not
compliedwith,DOMUSATEKNIK's guarantee of the appliance will automaticallybenulland void.
The quality of the fuel plays an important part in the performance and useful life of the boiler. The
firewood must have less than 20% water content (humidity). If the percentage of water is too high,
thecorrosion inside the boiler increases and the boiler performance is drastically reduced.
"Green" wood (recently cut) may contain over 50% humidity. Its caloric power is approximately half
of that of "seasoned" wood with 15% humidity. The greater the humidity of the wood, the slower
the combustion and the lower the flame temperature. This abruptly increases the amount of soot
and tar in the fumes.
Toreachdrylevelsintheair(<20%),the following drying times are recommended:
-Oak: 2.5years
-Beech,ash,fruittrees: 2years
- Linden, alder, birch: 1.5 years
-Pine,poplar,spruce: 1year
If the wood isnot cut (round wood), a minimumof2extramonths are required.
In addition to the cutting, another important factor is the physical size of the firewood. In relation
to its mass, smaller firewood has a greater surface than larger pieces of wood. It is easier to ignite
and its combustion is quicker. Large firewood may slow down combustion due to an unfavourable
volume/surface area ratio. This, unavoidably, implies a lower flame temperature and greater
contaminantemissions.
The following sizes of firewood are those recommended for a perfect and homogeneous service in
thecombustionchamber:
For Lignum NG 20, Lignum NG 30 and Lignum NG 40 boilers, the recommended log length is 50
cm. If the logs are short, it is recommended that they be placed lengthwise in the back part and
that the free spaceat the front befilledwithlogsplacedobliquely.

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Make sure the logs in the fuel loading compartment do not get stuck (avoid logs which are too
long). If the logs are too long, they do not fall properly and can cause gaps, causing a drop in the
boiler power. In order to avoidthis, it may be necessary to cut thetotal length in half.
Placetheroundedpartofthelogsfacingdown,to avoid any wedging effect.
If using briquettes, they must have a diameter of 6 to 10 cm. Their use is only recommended in
combinationwithfirewood.
Pay special attention to the energy density of the firewood, as a full load of pine wood is equivalent
to 2/3 of aload of beech wood and to½ a load of briquettes.

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3.4 Ignitionandpositioningofthefirewood
How the firewood is loaded into the housing is very important for an optimised combustion
process. It isrecommended that the firewood be inserted intothe loading compartment as follows:
Insert thick pieces of wood or stumps in the top area
only
4th Layer: Medium firewood
- Load the necessary amount in the compartment
3rd Layer: Ignition material
- Thick chippings, small chippings
2nd Layer: Paper, cardboard
- Ignite evenlythroughout the compartment
1st Layer: Small firewood
- Do not place immediately on top of the grill opening
- Place the chippings crosswise on top of the first layer
Ignition
tunnel
Chippi
Grill
opening
IMPORTANT: If there is no charcoal from a previous firewood load, put the first layer (at the bottom
of the fireplace) with abundant wood, as dry as possible, to obtain the proper amount of charcoal
(approximately10zm).
3.4.1 Ignitiontunnel
The ignition tunnel allows the combustion air to flow during ignition. Therefore, do not place any
combustion material on top of the opening of the grill during the ignition, leaving the ignition
tunnelfreeofobstacles.
3.4.2 Paper,cardboardandkindling
The fire should be lit with paper, cardboard and/or kindling. The cardboard should be placed
evenly on top of the ignition tunnel, across the entire surface of the first layer of small logs. If the
cardboardusedissmall,distribute it in paperball shapes. The kindling must be placed crossways
under the cardboard.
Theignitionprocessismanualand must be performed as follows:
-Partially loadthecombustionchamberwithsmalldrylogsandpaper,cardboardorwood
chips.
-Turn the boiler on and pressSTART to start up the induced draught fan.
-Lightapaperballusingamatchoralighter.
-The lit paperis placed with the paper/cardboard ontop of the ignition tunnel. The door can
bekeptslightlyopentoeaseignition.

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-Oncethefirehasspreadandembershaveformed, distribute them evenly, add therest of
theloadontopandfullyclosethedoors.
-Thecontrolautomatically regulates the combustion process.
3.4.3 Sawnwood(planks)
Sawn wood can be used in a similar way to kindling to ease ignition above the tunnel. The
planks should not be placed too close to each other, so that air circulates during ignition. It is
recommended that at least1 cm be left between planks.
3.4.4 Thick wood or stumps
Thick wood or tree stumps (part of the trunk joined to the root) can be placed on the top layer,
on top of several layers of firewood. Do not use more than one oversized piece of firewood or
stumpinthesameload.
3.4.5 Thick kindling andwoodworkingwaste
Thick kindling (G100, > 100mm), small material, woodworking waste, etc. must only be placed in
the loading compartment on top of at least three layers of firewood (approximately half of the
combustionchamber).
3.5 Unsuitablefuel
- Woodwith>20%humidity.
- Waste,plastics
- Paperandcardboard (only for ignition).
- Sawdust, wood shavings.
- Smallkindling.
- Coal.
- Material generally forbidden by legislation regarding atmospheric contamination and air
quality,such as treatedwood,beams,etc.
3.6 Combustionproductremoval
The Lignum NG boiler is a biomass boiler and it is essential for it to be connected to a flue, i.e. a
smoke duct able to create a pressure drop (which in this case should be between 0.10 and 0.20
mbar),incompliancewiththeapplicablelawsinthisregard.
The combustion product exhaustion ducts must be installed by qualified personnel and must
comply with the regulations in force. For the flue to create a pressure drop, the following
recommendationsshouldbetakenintoaccount:
- Itshouldbesuitablyinsulated.
- It should be independentlylocated, with a separate flue for each boiler.
- Itshouldbevertical,avoidinganyanglesgreaterthan 45º.

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- It should always have the same diameter. It is recommended that it be circular, and never any
narrowerthan theboileroutlet.
- It is obligatory to install a fume inspection plate with condensation collection, to remove
the condensation generated in the flue. Otherwise, the condensation may reach the inside of
the boiler and cause irreparable damage, which would not be covered by DOMUSA TEKNIK's
guarantee. The condensation pipe should lead to a drain outlet, as a large amount of water
may be generated. This connection must be made in compliance with the regulations for
draining off condensation water to the drain system.
- It is recommended that a draught stabiliser be installed to prevent any pressure drop
variations in the flue due to atmospheric conditions, which could affect correct boiler
combustion. This draught stabiliser must be installed below the fume inspection plate to
preventanyleakageofcombustiongases.
3.7 ElectricalConnection
The Lignum NG boiler must be connected to 230 V~ ac 50 Hz by the connector labelled “220V AC”
on the back of the boiler. Thesocketshouldhaveanappropriate earth connection.
The circulating pump must be connected to the 3-pin connector “ ”on the back of the boiler,
on the side opposite the connection tothe mains electrical supply.
3.7.1 DHWtankelectricalconnection(optional).
If there is an optional DHW tank, connect the DHW 3-way diverter valve in the 3-pin connector
“ ”. Connect the DHW temperature sensor in the controller, as indicated in the "Electrical
Diagram" .
The hydraulic installation for the 3-way DHW diverter valve should be made so that the heating
circuit(buffertank)canflowthroughthevalvewhenitisidle(notpowered):
HEATING
BOILER
DHW
NA/ NO
NC
V3V

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IMPORTANT: Before carrying out any work on the boiler's electrical installation, always ensure
itisdisconnectedfromthemains.
IMPORTANT: Make sure that none of the mains cables come into contact with a hot surface
(e.g. flue).
3.8 Exampleofaninstallation with a buffer tank
The Lignum NG boiler is equipped with an electronic control that can govern a circuit with buffer
tank, with an external circulation kit to prevent condensation in the heat exchanger. The heating
circuit must be regulated and controlled with an external regulator (not included in the boiler
control).
Thefigurebelowshowsanexampleofahydraulicdiagramofabuffertankheatinginstallation:
VS:Heatingsafetyvalve
VR:Anti-condensation thermostatic valve
VA: Drainvalve
BC:Heatingpump
BT: Buffer tank VDT: Temperature relief
valve
VC: Heatingexpansion vessel
BCD: Direct circuit pump
BCM: Mixed circuit pump
P: Automaticairbleedvalve
IMPORTANT:Itisobligatoryandessentialtoinstalla heating water buffer tank.

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3.9 Exampleofaninstallationwith a buffer tank and DHW tank
The Lignum NG boiler is equipped with an electronic control that can govern a buffer tank circuit,
with an external circulation kit to prevent condensation in the heat exchanger and, optionally, a
DHWtankloading circuit.
To control a DHW circuit, connect a DHW sensor from the hot water tank to the boiler (optionally
suppliedbyDOMUSATEKNIK)anda3-waydivertervalve(see "Electrical Diagram ”).
The figure below shows an example of a hydraulic diagram for a heating installation with radiators
and a DHW tank:
VS:Heatingsafetyvalve
VR:Anti-condensation thermostatic valve
VA: Drainvalve
BC:Heatingpump
BT: Buffer tank
V3V: 3-wayvalve
VC: Heatingexpansion vessel
BCD: Direct circuit pump
BCM: Mixed circuit pump
P: Automaticairbleedvalve
IMPORTANT:Itisobligatoryandessentialtoinstalla heating water buffer tank.

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4ADJUSTINGTHE COMBUSTIONAIR
The various stages of combustion (drying, pyrolysis, gasification and combustion) of the Lignum NG
woodboilertakeplaceinacontrolledmanner in different parts of the boiler.
The wood dries and decomposes in the loading compartment via the technique known as "inverted
draught", generating a combustible gas. The heat required for the decomposition reactions (pyrolysis
and gasification) is provided by the partial combustion of the firewood. The air necessary for the
gasification is called primary air.
The gas produced in the housing is mixed with the preheated secondary air and generates an
extremely high temperature combustion in the refractory chamber, reducing emissions and
increasingtheboilerefficiency.
The induced draught fan supplies the primary and secondary air to theboilerbysuction.
The air regulators or the boilers are set by default to optimal conditions for obtaining suitable fume
temperaturesandemissions.Therefore,theinitialairsettingoftheboilershouldnotbe modified.

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5TEMPERATURERELIEF SAFETY VALVE
In order to avoid the temperature inside the boiler reaching damaging levels, this valve opens and lets
the mains water supply pass into the interior coil, thereby dispelling the heat in a fully reliable manner.
This occurs when, for hydraulic reasons or due to lack of electric current, the boiler cannot dispel the
heat it is generating. Thisvalve is obligatory in Lignum NG boiler installations.
5.1 Operatingprinciple
The valve is regulated by the hot water from the boiler. If the water temperature is greater than
95ºC, the valve opens and lets the mains water through. This water moving in the coil absorbs the
boiler temperature and this prevents overheating and any damage to the boiler. The boiler
protectionsystemcorrespondswithStandardEN303-5.
5.2 Valveassembly
The temperature relief valve must be connected with free discharge to the safety heat exchanger
(in accordance with Standard EN 12828). The connection must not be blocked manually.
Furthermore, access must be granted to the heat protection mechanism and to the cleaning
inspection, once assembled. The minimum connection pressure for the safety heat exchanger is 2
bars.Thenominalpressureofthevalveis5 bars.
The temperature relief valve is installed up-current of the coil (placed respecting the flow direction
according to the arrow on the coil). The mains water supply must be connected directly to the
temperature relief valve.The connection is threaded, type Rp3/4"(DINEN10226).
IMPORTANT: It should not be possible to close the supply pipe so as to avoid any accidental
blockage.
IMPORTANT:Thecoldwaterpressureshouldnot depend on theelectricitysupply.
IMPORTANT:Thepipemustbethoroughlywashed before installation.

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6STARTING UP THEBOILER
6.1 Priorwarnings
Repair and maintenance of the boiler must be carried out by a qualified professional, authorised by
DOMUSA TEKNIK. For optimum functioning and conservation of the boiler, it should be serviced
annually.
Carefully read this instruction manual and keep it in a safe, easily-accessible place. DOMUSA
TEKNIK willnotbeliableforanydamages caused by failure to follow these instructions.
During some of the operating phases, a forced noise may be heard for a few minutes. This is normal
anddoesnotaffecttheboiler'sintegrityinanyway.
Before any servicing, disconnect the boilerfromthemains.
6.2 Fillingtheinstallation
The hydraulic installation must include a fill valve, a manometer, a safety valve, drain valves and the
necessaryhydrauliccomponentsforcorrectly filling the installation.
To fill the installation, open the fill valve until the installation manometer shows a pressure of 1 - 1.5
bars. The installation must be filled slowly, bleeding the air from the water circuit using the drain
valvesprovided for this purpose.Close the fill valve after filling.
IMPORTANT: Switching on the boiler with nowater inside couldresultinseriousdamage.
6.3 Start-up
Before beginning the start-up process, thefollowingmustbecompliedwith:
- Theboilermustbeconnected tothemains.
- Theinstallationmustbefilledwithwater(thepressuremustbebetween1and1.5bar).
Thefollowing steps are obligatoryin the start-up sequence:
- Removethecleaningbrushandtherakesuppliedwiththeboiler.
- Check the flue is correctly installed using the condensation inspection plate and a draught
stabiliser
- Checktheexternal hydraulicanti-condensation kitiscorrectlyinstalled.
- Checkthatthetemperaturerelief valveisproperlyinstalled.
- Iftheinstallationhasflow andreturnvalves,check theyareopen.
- Set the installationtype parameter (see “ Digitaldisplay and selecting parameters" ):
Thevalueis04ifthereisabuffertankwithoutaDHWtank.
Thevalueis02ifthereisabuffertank and aDHWtank.
- Set the boileradjustment mode parameter (see “ Digitaldisplay and selecting parameters" ):
Therecommendedvalueis02.

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6.4 Installationhandover
After the initial start-up, the installation engineer will explain to the user how the boiler works,
makinganyobservationsthey consider relevant.
The installer is responsible for clearly explaining to the user the functioning of any control or
regulation device formingpart of the installation but notsupplied with the boiler.

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7DIGITALDISPLAY AND SELECTING PARAMETERS
The Lignum NG boiler is equipped with a digital touch display for viewing and adjusting the different
boiler settings. The various parameters displayed onthemainscreenaredescribedbelow.
The various parameters displayed on the screen are described in the table below. You can browse
through the parameters by pressing the"F"button:
Selectingtheboilerset-pointtemperature,T1.
Default value (recommended): 80ºC
IftheDHWsensorisconnected and the hydraulic installationtypeselected
includes a DHWtank, after selecting the boiler temperature and pressing theF
button,theDHWset-point temperaturemustbe selected,T2(onlyvalidfor
installationwithDHWtank).
Default value: 55ºC
Afterpressing theFbuttonagain,selectthefumeset-pointtemperature, T3 (only
validforAdjustmentMode 03).
Recommended value: 180ºC
Ventilationtimeduringperiodswithnoheatdemand.
Default value (recommended): 10 s
Ventilationintervalduringperiodswithnoheatdemand.
Default value (recommended): 5 min
Maximum fan speed.
Default value (recommended): 99%
Minimum fan speed.
Recommended value: 50%
Settings for hydraulic installation type.
WhentheLignumNGboilerisinstalledwitha buffer tank (see Example of
installation with buffer tank
), the value of this parameter must be 04.

17
If there is a buffer tank and a DHW tank (see Example of installation with buffer
tankand DHWtank ),the selected parameter is 02. In order to work with a DHW
tank, a domestic hot water temperature sensor (see Electrical Diagram )anda3-
wayvalvemustbeconnected inthe" "connector(see Electrical Connection ).
IMPORTANT:Hydraulicinstallationtypes 01 and 03 are not operational in
Lignum NG boilers.
Boileradjustmentmode.Thereare3options:
-ClassicAdjustment.01
-PID adjustment based on the boilertemperature adjustment. 02
-PID adjustment based on the fume temperature adjustment. 03.
Recommendedparameter:02 (PID adjustment basedon boiler temperature)
Servicemenusymbol.
To select the parameters, press "F". Use the “+” and “-“ buttons to increase or reduce the value of the
selected parameter (the value will be flashing). Check that the value shown on the boiler temperature
set-pointindicatoristheonedesired.
IMPORTANT: If the fume temperature is selected as an adjustment parameter, it must be taken into
account that the real value is 10 times greater than that selected. For example 20ºC
means 200ºC.

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8BOILER MAINTENANCE AND CLEANING
8.1 Cleaning the boiler
8.1.1 Ashes
The ashes must be cleaned out regularly and properly after every 3 or 5 loads of firewood,
depending on the type of wood. The ashes accumulate in both the loading compartment and
therefractory combustionchamberandintheflue. Theashcouldbedepositedintheashbox.
Tocleantheboiler,followthesesteps:
-Theboilermustbecoldbeforecleaning.Wait2-3 hours after all the fuelhasbeenfinished.
- Open the top loading door, clean the ashes through the hole in the refractory burner using the
cleaning rake provided with the boiler. We recommend that you save part of the ashes and
carbonised wood to make it easier to light the next time. Avoid scraping the rake on the
middle refractorypart in order toavoidabrasionofthe part.
- Close the top loading door and open the bottom front door. Remove the ashes that have built
upinsidethecombustionchamberandsurroundingareas.
- Clean the flue by moving the lever towards the boiler approximately 10 times. Perform full 90º
cycles.
NOTE: The flue cleaning lever can be placed on the opposite side of the boiler. To do so,
remove the sides, the back part of the roof and the flue lid, loosen the lever and the arm of
thecleaningaxle,removetheaxleandplace it in the reverse position.
8.1.2 Tar
Clean the tar from the metal surface of the fuel loading chamber using the scraper. The
gasification process produces tar and the amount will depend on the type of wood, its humidity
andthewaterinletandoutlettemperatures.It is recommendedthat itbe cleaned once a month,
althoughthefrequencymayvarydependingonthetype of wood used.