ARCA AIRPELLET User manual

TECHNICAL MANUAL
AIRPELLET
8 KW, 10 KW, 12 KW
Stoves
LIBxxx 56 pag - Rev. 3 - 15/01/2013

CONTENTS
1. INSTALLATION ........................................................................................................................5
1.1 Norms and declarations of conformity................................................................................6
1.2 Installation ..........................................................................................................................6
1.3 Dimensions....................................................................................................................... 11
1.4 Positioning........................................................................................................................12
1.5 Turning on ........................................................................................................................15
1.6 Maintenance.....................................................................................................................16
2. USE AND MAINTENANCE.....................................................................................................17
2.1 Regulations and declaration of conformity .......................................................................18
2.2 Wiring diagram ................................................................................................................. 19
2.2.1 The remote control.................................................................................................... 20
2.3 User interface ................................................................................................................... 21
2.3.1 Description of the console ........................................................................................21
2.3.2 Use of the bottons..................................................................................................... 21
2.3.3 Meaning of the ligths lights LEDs ............................................................................. 22
2.3.4 Display......................................................................................................................22
2.4 Operating mode................................................................................................................ 23
2.4.1 Turning on the stove.................................................................................................23
2.4.2 Loading the pellet ..................................................................................................... 23
2.4.3 Load flame light ........................................................................................................24
2.4.4 Stove in work ............................................................................................................24
2.4.5 Changing the heating power.....................................................................................25
2.4.6 Changing the room temperature............................................................................... 25
2.4.7 The ambient temperature reaches the set temperature (set temperature)............... 25
2.4.8 Stand-by ...................................................................................................................26
2.4.9 Turning off the stove.................................................................................................27
2.5 Menu ................................................................................................................................ 28
2.5.1 User Menu ................................................................................................................28
2.5.2 Menu - M1 - Set clock............................................................................................... 30
2.5.3 Menu - M2 - Set chrono ............................................................................................32
2.5.4 Menu - M3 - Language selection ..............................................................................35
2.5.5 Menu - M4 - Stand-by ...............................................................................................35
2.5.6 Menu - M5 - Buzzer ..................................................................................................35
2.5.7 Menu - M6 - Load initial ...........................................................................................36
2.5.8 Menu - M7 - State stove ........................................................................................... 36
2.5.9 Menu - M8 - Set Technic .......................................................................................... 37
2.5.10 Menu - M9 - Escape ............................................................................................... 37
2.6 Alarms...................................................................................................................................38
2.6.1 Black-out electricity .......................................................................................................38
2.6.2 Flue temperature probe alarm....................................................................................... 39
2.6.3 Alarm over temperature flue gas ..................................................................................39
2.6.4 Alarm encoder flue gas failure....................................................................................... 39
2.6.5 Alarm misfire .................................................................................................................40
2.6.6 Alarm no pellet ..............................................................................................................40
2.6.7 Alarm temperature thermal safety .................................................................................40
2.6.8 Alarms flue gas pressostat ............................................................................................41

2.7 TROUBLESHOOTING..........................................................................................................42
2.8 Technical Menu.....................................................................................................................44
2.8.1 M8-1 Setting factory .................................................................................................45
2.8.2 M8-2 Other settings.................................................................................................. 45
2.8.3 M8-3 Type of pellet...................................................................................................45
2.8.4 M8-4 Type of chimney.............................................................................................. 45
2.8.5 M8-5 Bank of database ............................................................................................ 46
2.8.6 M8-6 Test outputs ....................................................................................................47
2.8.7 M8-7 Reset partials hours ........................................................................................ 47
2.8.8 M8-8 Alarm reset......................................................................................................47
2.8.9 Parameters...............................................................................................................48
2.8.10 Other parameters .....................................................................................................49
2.9 Cleaning and Maintenance ...................................................................................................50
3
The installation of the pellet stove must be realized by qualified technician observing the technical
norms, the national and local laws in force.
Observe the safety notes concerning the installation, the maintenance and the use contained in
this manual

1. INSTALLATION
AVVISO!
Read carefully the precautions to follow correctly the recommendations .
Do not try to install the heater: get in touch with authorized personnel who have
the relevant training.
In case that there is a breakup in the stove or it didn't correctly work, to put on in contact with
the of Assistance Service of zone: whatever attempt that does him to get off pieces or to realize
the maintenance of the stove can expose the consumer to a danger of power drains. The stove
contains pieces whose substitution must have realized from the Assistance Service.
The stove is a appliance of heating; its pieces can reach extreme temperatures and the contact
with the same without the suitable protection you can provoke scorching of different degree.
Pay particular care to the children.
In the case to realize a removal, puts on in contact with the Assistance Service for its withdrawal
and new installation.
Insert neither the fingers nor other objects in the fissures of exit of the pipe of air.
Inside the instrument there is a high speed fan that could cause serious personal wounds. Pay
special attention to the children
Doesn't directly remain during long time statement to the flow of warm air.
The direct and prolonged exposure to the warm air could be dangerous for the health. Pay a
particular attention in that environments in which is present sick, children or old person.
In the case in which the stove doesn't work well, immediately stop the appliance, disconnect the
corresponding automatic interrupter and put on in contact with the Assistance Service. The
prolonged use of the appliance under said conditions could cause fires or sparks.
AVVISO!
During the operation of installation of the stove, maintains the children far from of the zone of
job to avoid unexpected accidents.
Don't stop neither cover in some way the body of the stove, neither obstructs the situated
loopholes in the superior part. The obstruction of said loopholes could cause fires.
Don't use the stove in zones that contain instruments of precision, neither works of art. The
quality of the preserved objects would be deteriorated.
Don't expose animals neither plants directly to the flow of air of the stove. The exposure
prolonged to the direct flow of the stove could have some negative effects in plants and
animals.
Occasionally ventilate the environment until it is using the appliance. An insufficient ventilation
could be the cause of an insufficiency of oxygen in the environment.
Don't expose the stove to the water. The electric isolation could result ruined, with , as
consequence, the possibility of short-circuits.
Verify the conditions of installation to locate the possible damages that stove could have.
Don't use gas inflammable gas next to the heater. Disconnect the automatic interrupter if the
instrument is not used during long time periods
We test the starting of all of our products.
5

1.1Norms and declarations of conformity
1.1 Laws
Our factory declares that the stove is
conforming to the following norms and
European directives ok CE marking.
89/336 and 2004/108/CE, EMC directive and
following amendments.
2006/42/CE, Machinery Directive,
89/106/CE, Product for Construction.
EN 60335-1, EN 50165, EN 50366, EN
55014-1, EN 61000-3-2, En 61000-3, EN
14785
The installation of appliances has to comply
the local and national legislation and the
European directives.
Responsibility
The manufacturer won't accept direct or
indirect responsibility, civil or penal derived
from:
an insufficient maintenance;
not observation of the instructions
contemplated in the present training manual.
an use of this appliance ont allowes by the
Country of destination;
the installation from personal unqualified or
without the pertinent formation.
the changes and reparations not authorized
from the manufacturer.
the employment of non original spare parts
non original.
The use of pellet not approved by the
manufacturer.
1.2 Installation
Chimney of exhaust gas
To prevent malfunction of the product is
critical to have a chimney installed in a
workmanlike manner and use a good quality
pellet.
The chimney of exhaust gas must comply the
followings requisite:
It shouldn’t be connected to any other
type of fireplace, stove, boiler or bell of
ventilation (fig 1).
It has to be installed to a distance adjusted
from where material fuel there is or
inflammable through a hollow of air or
opportune isolation.
The inside section will have to be uniform,
preferably circular: the square or
rectangular sections should have angles
rounded off with a greater ray of 20 mms,
a maximum relationship among the sides
of 1,5; the walls have to be the smoothest
possible not to have particularly narrow
zones, irregular curves or discontinuity or
deviations from the superior axle to the
45°.
fig. 1: methods to install the exaust gas ducts
6

All the appliances should have must have an
own chimney with an equal or superior
diameter to the pipe of gone out of the stove
and a non inferior height to that declared;
In the same environment not ever use two
stoves, a fireplace and a heater to firewood, a
heater and a kitchen, etc, because the
draught of one of these appliances could
damage that some other. The ducts of
collective ventilation that can reduce the
atmospheric pressure in the environment of
installation, are not admitted, even if installed
in environments that are adjacent to the site
of installation, or to communicate with it.
You recommends that the flue gas both duct
endowed with a chamber that accumulates
the solid materials. This chamber must have
done so that can easily be opened and can
easily be inspected through a hermetic cover.
the pipe of the flue gas ducts doesn't have to
pass through inflammable material;
Chimney
The superior part of the fireplace has to
respect the followings conditions:
Should have an useful diameter of exit non
inferior to double of chimney.
The top of the fireplace of the roof that
remains to contact with the outside (for
example, in the case of open lofts or
mansard) must be covered with bricks or tiles
and in every case must be well isolated.
Must be builds for holding out of the chimney
the rain, the snow, and extraneous bodies, so
that the unload of flue gas is not prevented
The top of the fireplace has to be of a type
against back wind above to the peak of the
roof.
The structures or other obstacles that over
the superior part of the fireplace it doesn't
have to be too much next to the superior part
of the same fireplace
fig. 2: characteristics of the chimney pot.
7

Chimney
fig. 3
The customer has to own the" certified of conformity of the chimney".
In the flue must be a vacuum of 12 Pa
with the stove working.
The descharge of flues gas represented in
the following figures is the optimal in
demand solution to also assure the
disposal of the flues gas with out fan
caused by a possible lack of electric
energy. The least gradient of 1.5 meters
among unloaded back of the stove and the
terminal to “T” external to the building, it
assures the disposal of the flues residual
gas of the combustion in the case
described (Otherwise these would
stagnate inside the hearth and they would
go to escape in the environment with
besides the possibility of bursts). The
brought figures point out the optimal
solution when is decided for the unload the
flues gas over the roof or inside the
chimney. In the case to unload the flues
gas over the roof him proceeds foreseeing
to insert a link “T” with cover of inspection,
stirrups of link adjusted to the height of the
chemney, converges that cross the roof
and chimney pot of protection against bad
weather.
fig 4
8

If you want to use the classical chemney in
masonry a link foresees him to “T” with a
cover of inspection, stirrups of support
adjusted.
If the chimney is very old is obligation to
restore to pipeline health introducing it in
steel or porcelain of the diameter not superior
to 150 mms. Adequately seal the part of entry
and exit in the chimney in comparison to the
part in masonry.
It is forbidden the use of a net to the extremity
of the pipe of unloading, since it could cause
the bad operation of the stove. If the duct
smokes is installed in fixed way it is
opportune to foresee some openings of
inspection to be able to effect the inside
cleaning especially in its horizontal lines. To
such intention follow the scheme. How much
described above it results essential to be able
to remove ash and residual that can be
created during the process of combustion.
The system of unloading flue gas will have to
entirely be for the stove, it is not permitted to
realize the I unload in common with exits with
other appliances. The I unload of smoke it
realizes him through the pipe of 8 cm,
positioned in the back part.
It will be had to prepare one" T" with a cover
of receipt of the condensation.
The I unload of flue gas of the stove it will
owe is go connected to the outside using a
steel pipe or black resistant thin to a
temperature of 450°C, without obstructions.
The pipe will be tight.
To assure that the pipes are tight and their
possible isolation stopped it is necessary to
use material resistant up to 300 °C, silicone
or suitable mastic for high temperatures.
The horizontal sections can have until a
longitude of 2 meter. Is possible to have three
curve of 90°at maximum. If the pipe of flue
gas is not inserted in the exit of flue gas, you
need a opportunely isolated vertical section of
a minimum of 1,5 meter, except in case of
evident danger for the safety , and a terminal
with a device of back wind (fig. 5).
The vertical duct can be in the inside or in the
outside. If the duct of the flue gas is in a
fireplace, this will owe this certificate for solid
fuel and if it is greater than 150 mm in
diameter, a change is necessary inserting an
inside insulation that isolates flue gas from
the contact of the bricks.
It has to be possible to inspect all the
sections of the duct of flue gas. If it deals with
a fixed duct, it will have to have orifices to
realize works of inspection and of cleaning.
The adjacent place must not be use as
garage neither to be a space without
ventilation or exchange of air, a storage of
inflammable material neither to be used for
an activity that supposes a danger of fire.
fig 5: inside installation of flue gas ducts that it
should be realized in conformity with the norms
fig. 6: outside installation of flue gas ducts that it
should be realized in conformity with the norms
9

The stove shouldn’t be in the same place in
which extractors are found, gas apparatuses
type B neither, in any case, appliance or
devices that put in depression one the place
The stove will owe with the necessary air is
go installed for guaranteeing a regular
operation of the combustion and an
environmental comfort.
To make sure him that the environment in
which the stove is installed has enough
ventilation install a duct of taking of air with a
diameter least recommended of 50 mms to
allow the entrance of the air of the outside.
The taking of external air must have
communicated with the stove and being
positioned so that remains interrupted. It has
to be protected with a permanent grate that
cannot close or another adjusted protection
provided that the least diameter is not be
reduces.
Also the flow of air can get him of an adjacent
place in local in which installed the stove
provided that says flow can freely cross the
permanent orifices communicating with the
outside.
10

1.3 Dimensions
Dimensions of mod. 8 e 10 KW pellet stoves
fig.7
F: flue gas Ø 80mm pipe
A: Ø 48-50 mm air pipe
11
455
877
195
105 140
177
471
490
937
F
A

Dimensioni della stove a pellet mod. 12 KW
fig. 8
F: flue gas Ø 80mm pipe
A: Ø 48-50 mm air pipe
12
F
A
105 140
285
267
455
471
490
967
1027

1.4 Positioning The stove is
equipped with an electric cable that must be
connected to a female socket of 230 Volts and 50
Hz, with with a bipolar switch breaker. The
variations of tension more of the 10 percent can
put in danger the stove that doesn't have a
differential interrupter.
The electric system has to observe the norms; to
concretely verify the efficiency of the circuit of
mass to earth. The cable of power supply has to
have a suitable diameter for the feeding of the
stove.
The stove will have to be completely in plain.
Check the load capacity of the soil below.
Install the stove in an environment where you
spend your life in a way that usual to heat evenly.
Before deciding where to place the stove, you will
have to take into account the following:
The air used for combustion must not come from
a garage or a room with no ventilation or air
exchange, but rather to open space or outdoor.
The stove must not be installed in a bedroom.
fig 9: minimum distance from objects
It is better to install the stove in a large central
room of the house to ensure maximum circulation
of warm.
Safe distance from the fire
The stove should be placed taking into account
the following safety condition.
The distance from the sides and the rear part
must be 20 cm from the non-flammable material;
The distance from the sides and the rear part
must be 40 cm from moderately flammable
material;
A highly flammable material is not to be used at a
distance less than 80 cm in front of the stove;
If you install the stove on a floor of combustible
materials, the stove must be placed on a sheet of
material that insulates against heat and it is wider
on the sides of 20 cm, and 40 cm in front;
Do not place objects within the flammable
material, or any material into the stove or in the
safety distance which may cause the malfunction
of the stove;
In addition, it is recommended to maintain all
elements of fuel or flammable material, such as
wood siding, wood furniture, flammable liquids,
etc clothes. away from the radiating area of
radiation of the stove, and, in any case, for a
minimum distance of 1 m from heating block
(fig.9);
In case the flue pipe passes through walls of
wood or another combustible material, it is
necessary to isolate the exhaust pipe of smoke
with ceramic fiber and another material that has
the same characteristics.
Aspiration combustive air
The air of combustion has to integrally take
preferably from the external environment. To
get a correct and sure position of the return of
air, will need to concern all the precautions
(fig.10). There is a series of distances to observe
for avoiding that to the air of the fuel is drawn out
from other places; the opening of a window could
for example, cause eddies in the external air,
picking them up of the stove.
fig.10: distance from wall
13

Instructions for installing the fire protection
Put the protective plate of the fire following the instructions in the following figures.Install the protective plate
of the fire making sure that you have properly positioned the 3 hooks as shown.
Fig. 11: mount the plate fire
fig 12 fig 13 fig 14
fig. 15
Componenti in porcellana di maiolica
La stove è ricoperta con porcellana semi-refrattario maiolica (no si deve confondere, pertanto con altri
materiali simili come la porcellana comun). I punti od orifizi sono caratteristici di questa porcellana di
maiolica fatto a mano, e pertanto non si considerano difetti, e né tanto minimamente hanno influenza sulla
vita del prodotto
14

1.5 Turning on
Before lighting the fire in the stove, carefully
read the instructions for use and
maintenance.
Remove from the pellet storage that is
located under the top cover of the stove,
where is located the display, the components
and documentation that are included in the
packaging, making sure that the deposit is
free from any foreign matter.
Unroll the cable of the ambient sensor which
is placed in the rear of the stove without
placing it on the pieces of the hot stove.
Correctly connect the output of the pellet
stove fumes.Fill the deposit pellet 6 mm in
diameter.
Open the door and check that the grate is
properly inserted into its slot, and that the
seal is properly mounted.
Close the door. Do not open the door until it's
working. Do not open the store until the pellet
stove is operating.Connect the stove with the
appropriate power cord received with the
stove.
Before the first start of the
stove,with the dispaly in OFF, select M6
(see par.2.5.7 on page 36) To do this, press
and hold the P1 for about 2 seconds. When
appears the message M1, press the P2
button until appears in the display M6. Then
press P3 to exit the menu M6.
Put the switch at the back of the stove in the
"1" position.
Press the ON / OFF button for 2
seconds and the stove will begin its ignition
cycle
For the detailed explanations of the operation
see the chapter 2 “Use and Maintenance” .
fig. 16
15

1.6 Maintenance
WARNING!
During the first firing is necessary to ventilate well around since the early hours of operation could
emanate unpleasant odors due to the fumes of the paint and the fat that is present on the plates.
If during normal operation of the stove, the flue gas temperature reaches 220 ° C, a parameter that
can be modified to a technician, the discharge of fumes is modulated in the following way:
- Flue fan motor speed;
- Auger pellet at minimum speed;
- Heat exchanger tangential fan at maximum speed.
This mode of operation reduces the temperature of the flue gas. When the temprature of flue gas
decrease below the level of 220 °C, the stove restore the speed of the three engines to the
previous settings.
When you restore the power, after a black-out, if the time of power failure is less than 30 seconds,
the stove will restart in "WORK", otherwise it will activate the alarm AL1 Alar A1 Blac-out and the
stove enters the shutdown sequence.
Operations to be carried out for the Assistance Service each year,
before turning on the stove
A general cleaning of the interior and exterior.A through cleaning of the heat exchange pipes
A through cleaning and descaling of the grate of the cavity relative.
Clean the engine and check the bearing clearence and unions mechanisms.
Clean the flue gas channel (re-seal tubes) and cavity-extractor fan.
Clean the flue gas pressostat, replace the silicone tube.
Check the sensor of temperature.
Clean, inspect and descale the cavity of the ignition coil, replacing it if necessary.
Visually inspect the electrical cables, connections and power cord.
Clean the pellet and verify the operation of the cochlea.
Replace the door seal.
Test auger, fan, ignition.
Check the electrical parts and electronic components.
Check the channel, creating a possible cleaning.
The figures are approximate and may differ from the original product. Images are an example to
understand the way in which the product works.
16

2. USE AND MAINTENANCE
Dear Customer,
Thank you for choosing one of our products, the result of many years of experience and a
continuous search for higher quality in terms of safety, reliability and performance.
This booklet contains all the information and helpful tips to use your product with maximum safety
and efficiency.
Please note that the first switch must be by our Authorized Service
Center which verifies the installation and complete the form of the
guarantee.
Improper installation, maintenance performed poorly absolve the manufacturer from any damages
arising from the use of the stove.
The appliance should not be used as an incinerator, nor should they be used fuels other than
pellets.
This manual has been prepared by the manufacturer and is an integral part of the product and
must accompany him throughout his life. In case of sale or transfer of the product always ensure
the presence of the book because the information contained in this manual are addressed to the
purchaser and to all those people who for various reasons do the installation, use and
maintenance.
Carefully read the instructions and information contained in this manual before installing or using
any repairs.
The instructions in this manual will ensure safety and product, operating economy and a longer
operating life.
Careful planning and risk analysis made by our company have allowed the creation of a safe
product, but before performing any operation, it is recommended to strictly follow the instructions
in this document and keep it handy.
Exercise care in handling the ceramic components where present.
The product should not be placed near a wall of wood or any other combustible material, it is also
necessary to maintain the safety distances.
During operation, some parts of the stove (door, handle, casing) can reach high temperatures.
Therefore exercise great care and take precautions especially if there are children, the elderly,
the disabled and animals.
The installation must be performed by authorized persons (Authorized Service Center).
Diagrams and drawings are provided for illustrative purposes, the manufacturer in order to pursue
a policy of continuous product improvement may change, without notice, any changes it deems
appropriate.
It is recommended to use gloves to handle pellet loading door and handle for opening the door
It is forbidden to install in the bedroom.
Never cover in any way the body of the stove or occlude theslits placed on
the upper side when the appliance is in operation.
All our stoves are tested on the production line
In case of fire, disconnect the power supply, use a fire extinguisher and possibly call the Fire
Department. Then contact an Authorised Service Centre.
17

2.1 Regulations and declaration of conformity
Our company states that the stove is manufactured in accordance with the following standards and
European Directives for CE marking:• 89/336 EC and 2004/108 EC, the EMC Directive, as amended;
•2006/95 EC Low Voltage Directive and subsequent amendments;
• 2006/42 EC (Machinery Directive);
• 89/106 EC (Construction Products);
All local laws and national and European standards must be met when installing delthe appliance;
• EN 60335-1, EN 50165, EN 50366, EN 55014-1, EN 61000-3-2, EN 61000-3-3, EN 14785.
Information pertaining to a security
Please read this instruction manual and maintenance before installing and operating the stove.
If in doubt, contact your dealer or authorized service center.
• The pellet stove must only be operated in rooms used as a dwelling. This stove, being regulated by an
electronic board, allows a completely automatic and controlled combustion; in fact, the controller adjusts the
ignition phase, 5 power levels and the shutdown phase, guaranteeing a safe operation of the stove;
• The container used for the combustion does fall into the receptacle largely from the ashes produced by the
combustion of the pellets. However, it is advisable to check daily the container, since not all the pellets have
high standards (only use quality pellet recommended by the manufacturer);
• The glass is provided with a special air circulation for self-cleaning of the same, however, it is not possible
to avoid a slight grayish coating on the glass after a few hours of operation.This also depends on the type of
pellet used. Some pellets may soil more than others.
Responsibility
With the delivery of this manual, we do not accept any liability, both civil as penal, accident derivatives of
partial or total non-fulfillment of the instructions contained therein.We disclaim all responsibility originating in
the use of inadequate stove, misuse by the user, modifications and/or repairs, the use of non-original spare
parts for this model.The manufacturer disclaims any responsibility or liability direct or indirect result of:
• Insufficient maintenance;
• Non-compliance with the instructions contained in the manual;• Improper security guidelines;
• Installation not in accordance with the rules in force in the country;• Installation by unqualified and
unprepared;
• Modifications and repairs not authorized by the manufacturer;• Use of non-original spare parts;• Exceptional
events.
The stove must be turned on pellet quality, 6 mm diameter of the type
recommended by the manufacturer;
Before connecting electrically the stove, must be prepared the pipe connecting the
exhaust duct with the flue gas;
The protection grid located inside the deposit of pelletsyou do not have to ever
take away;
In the environment where you place the stove must have sufficient air exchange;
Never open the door of the stove during operation thereof.
When the stove is turned on, its surfaces surfaces, the glass, the tube flue gases
are found at high temperature:
during operation, do not touch these parts without adequate protection
keep the pellets in a dry and not humid;
keep at a safe distance, safe from stove fuel and other flammable materials.
18

2.2 Wiring diagram
fig. 17
display
NB to enable an eventual T.A. external (external thermostat / contact), press P1 to bring the temperature to
the minimum setting. You will see the word T-E. Confirm with the P3
19
N.A.
C
C
1
3
OFF
1
-+2 3
P1 P3P2

2.2.1 The remote control
Using the remote control you can adjust the heating
power, the temperature
desired and the automatic on / off the appliance.
S = indicator light indicating the pressure of each key.
Correspondence of display keys with remote control
keys
1 = p3+p5
2 = p2
3 = p3
4 = p4
5 = p5
Fig. 18
To turn on the stove, press buttons simultaneously for 1 second 2 and5;
the device automatically enters the start-up phase. This is followed by the start-up phase which
allows the stove to develop and settle the flame.
Once the start-up phase, the stove goes into normal operation buttons 4 and 5 it is possible to
adjust the heating power while using buttons 2 and 3 you can adjust the desired room temperature.
To turn off the stove and hold simultaneously for three seconds the buttons 3 and 5, the display will
show "OFF".
The remote control works with a MN21 12V battery (type gate openers).
To replace the batteries, open the cover on the back as shown in the figures below.
fig 19
Open by pressing the part shown in fig. 19
20