BENEKOV K14 Quick start guide

BOILER OPERATION AND INSTALLATION
GUIDE
BENEKOV K14
BENEKOV K20
BENEKOV K25

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•Dear customer,
Thank you for purchasing an automatic wood pellet boiler BENEKOV
models K14, K20 and K25 and thus showing confidence in the company
BENEKOVterm Ltd. Horní Benešov.
To get used to the correct handling of your new product right from the
start please read these operating instructions, mainly chapters 7 and 8.
Please be advised to observe the following information and observe the
instructions of both the manufacturer as well as the service company
that installed the boiler.
An initiation test of the boiler type was conducted by Vysoká Škola
Báňská - Technical University of Ostrava, authorized person 260
(Certificate No. 3-17 dated 25th August 2017).
In accordance with Government Directive no. 176/2008 of the “Col.”, appendix
1, point 1.7.4. these are
ORIGINAL USER’S INSTRUCTIONS.
Copyright 2017 Leopold Benda jr. and co., licenced to BENEKOVterm Ltd.
All rights reserved
All text, images are subject to copyright and other intellectual property protection.

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Table of contents
1. Boiler use and advantages.................................................................................................................. 4
2. Boiler technical specifications............................................................................................................. 4
3. Recommended boiler fuel................................................................................................................... 5
4. Boiler description................................................................................................................................ 6
4.1. Boiler construction........................................................................................................................... 6
4.2. Burners description........................................................................................................................ 11
4.3. Burners operation.......................................................................................................................... 11
4.4. Operation, control and safety features of the boiler....................................................................... 13
4.5. Boiler accessories.......................................................................................................................... 14
5. Boiler positioning and installation...................................................................................................... 14
5.1. Regulations and directives............................................................................................................. 14
5.2. Boiler position options.................................................................................................................... 16
5.3. Connection to the chimney............................................................................................................ 19
6. Commissioning the boiler - instructions for contractual service companies.................................... 19
6.1. Connecting dimensions ................................................................................................................. 20
6.2. Installation of the ceramic parts into the combustion chamber ..................................................... 21
6.3. Checks before commissioning the boiler....................................................................................... 21
6.4. Commissioning the boiler .............................................................................................................. 22
7. Boiler operation by the user.............................................................................................................. 22
7.1. Feeder calibration.......................................................................................................................... 22
7.2. Lighting the boiler up ..................................................................................................................... 23
7.3. Boiler operation.............................................................................................................................. 23
7.4. Boiler decommissioning................................................................................................................. 24
7.5. Residual risks and their prevention................................................................................................ 25
8. Boiler maintenance........................................................................................................................... 25
9. Burner maintenance, settings and service ....................................................................................... 26
9.1General instructions...................................................................................................................…..26
9.2 Cleaning the tubular aeration rotary chamber ...........................................................................…..26
9.3 Setting up airflow into the furnace .................................................................................................. 28
9.4 Lubricating furnace bearings .......................................................................................................... 29
9.5 Replacing the ignition coil............................................................................................................... 31
9.6 Diagram of burner electrical connection......................................................................................... 32
10. Troubleshooting.............................................................................................................................. 35
11. Guidelines for compliance with the environmental parameters of the product................................ 37
12. Instructions for disposal of the product after its service life............................................................. 37
13. Warranty and damage liability......................................................................................................... 37
ATTENTION!......................................................................................................................................... 39
Appendix to the “Warranty Certificate” for customer - user................................................................... 40
Declaration of Conformity for K14, K20 and K25 boilers....................................................................... 41

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1. Boiler use and advantages
Use of the boiler:
The BENEKOV K14 hot water boiler is designed to heat small or low-energy houses, chalets and other
buildings whose thermal loss does not exceed 15 kW.
The BENEKOV K20 hot water boiler is designed to heat small or low-energy houses, chalets and other
buildings whose thermal loss does not exceed 20 kW.
The BENEKOV K25 hot water boiler is designed to heat small or low-energy houses, chalets and other
buildings whose thermal loss does not exceed 25 kW.
BENEKOV K14, K20 and K25 boilers are designed to burn wooden pellets.
Boiler advantages:
•the boilers meet the requirements of boiler class 5 and ECODESIGN
•high efficiency of the boilers
•minimal environmental impact
•automatic boiler operation
•patented burner solution with self-cleaning furnace
•automatic boiler ignition and extinguishing
•mechanical delivery of the fuel from external feeder to the furnace
•simple, time-efficient use and maintenance
•low operating costs
•modern design
2. Boiler technical specifications
Chart 1 Dimensions and technical parameters of the boilers
Boiler type
BENEKOV
K14
BENEKOV
K20
BENEKOV
K25
Weight
kg
215
310
Volume of the water tank
dm3
45
70
Diameter of the flue pipe
mm
115
145
Boiler heat exchange surface
m2
1,71
2,16
Fuel store capacity
dm3
200
370
kg
120
222
Boiler dimensions: width
depth
height
mm
mm
mm
889
1035
1453
1256
1186
1453
Diameter of the fuel store replenishing
aperture
mm
542x388
635x690
Highest allowed operating pressure
bar
2,0
Testing pressure
bar
4,0
Recommended heating water operating
temperature
°C
65 - 80
Temperature controller setting range
°C
60 - 85
Hydraulic loss of the boiler: ∆ T = 10 K
∆ T = 20 K
mbar
mbar
5,72
1,64
19,07
4,71
23,84
5,89

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LpAsound pressure level
dB
54,7 ± 3,2
Required chimney draught
mbar
0,05 –
0,08
0,05 –
0,09
0,05 –
0,10
Boiler connections: - heating water
Js
G 1”
- return water
Js
G 1”
Connection voltage
1 PEN 230V / 16A / ~ 50 Hz
Maximum electrical input power
W
395
429
Electrical rating
IP 20
Chart 2 Thermal-technical parameters of the boilers
Boiler type
BENEKOV
K14
BENEKOV
K20
BENEKOV
K25
Rated output
kW
15
20
25
Adjustable output
kW
4,5 –15
6 –20
7,5 –25
Fuel consumption
kg . hr-1
1,0 –3,2
1,3 –4,5
1,7 –5,8
Output in inhibition mode
kW
1
1
1
Fuel consumption during inhibition
kg . hr-1
0,25
0,25
0,25
Burning time at rated output and full fuel
store
hr
40
28
22
Boiler class according to EN 303-5
5
5
5
Eco design
Yes
Yes
Yes
Flue gas temperature
- at rated output
°C
115
135
150
- at minimum output
°C
90
90
90
Efficiency at rated output
%
91,3
90,4
89,5
Efficiency at minimum output
%
88,1
89,1
90,0
Mass flow rate of flue gases at exit point
- at rated output
kg . s-1
0,007
0,008
0,013
- at minimum output
kg . s-1
0,003
0,004
0,005
Electrical input power at rated output
W
45
55
64
Electrical input power at minimum output
W
29
29
29
Electrical input power in STAND BY mode
W
3
3
3
3. Boiler fuel specifications
Chart 3 specifies required (warrantied) types of fuel for BENEKOV K14, K20 and K25 boilers:
Chart 3 Required fuels
Fuel type according
to EN 303-5
C1 –wooden pellets
Grain (average)
[mm]
6 - 8
Length
[mm]
max. 30
Bulk density
[kg/m3]
600 - 650
Water content
[%]
max. 12
Ash content
[%]
max. 1,5
Calorific value
[MJ.kg-1]
min. 17
WARNING! Poor fuel quality can significantly affect the performance and emission parameters
of the boiler.
The pellets must meet the requirements of standard EN ISO 17225-2 Solid biofuels –Specification and
fuel grades –Part 2: Sorted wooden pellets.

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4. Boiler description
4.1. Construction of the boiler
The boiler design meets the requirements of:
EN 303-5: 2013 - Boilers for central heating - Part 5: Boilers for central heating for solid fuels, with
manual or automatic delivery, rated thermal outputs up to and including 500 kW - Terminology,
requirements, testing and marking.
The main part of the boiler is a boiler body welded from steel boiler plates. All parts of the boiler body
at the interface flue gas/heating water are made of 5 mm thick sheet metal. The combustion chamber
with a burner is at the front part of the boiler body, the 3-level plate fin exchanger is at the back of the
boiler body. This is the critical point of heat transfer between the flue gases and the heating water. The
side walls of the combustion chamber of the boiler body are protected by ceramic plates which regulate
the flow of the flue gases and assist in perfect combustion.
On the upper wall of the boiler body in the front part is a hollow where the heating water temperature
sensor and the emergency thermostat sensor are located.
The burner is attached to the side wall of the boiler body. Its rotary part (the furnace), in which the
combustion itself takes place, is made of heat-resistant stainless steel. Other burner elements are
galvanized or painted for protection.
Under the burner in the boiler there is an ash drawer.
The fuel store is next to the boiler. The fuel is delivered from here via the stainless feeder upwards and
falls through the overflow (flexible hose) into the burner. Depending on the position of the fuel store in
relation to the boiler body, the boiler is manufactured in two versions:
•right version –the fuel store is to the right of the boiler body when viewed from the front
•left version –the fuel store is to the right of the boiler body when viewed from the front
The burner fan is integrated into the burner assembly. The amount of combustion air is regulated by
the boiler programmer.
The heating water inlet and outlet for connection to the heating system are located at the back of the
boiler and are made of two outlets with G 1" internal thread. The outlet with G 1/2 " thread at the
bottom on the right is for installation of the drain valve. There is an exhaust pipe to discharge the flue
gases into the chimney at the rear of the boiler at the top.
The boiler body, its lid and door are insulated with harmless insulation which reduces heat loss to the
surrounding area.
The steel cladding is colour-treated by high-quality powder coating.

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Fig 1 Front and rear view of the BENEKOV K14 boiler
1. fuel store lid
2. fuel store
3. chain to secure the feeder
4. throttle flap locking bolt
5. store feeder drive
6. fuel feeder inspection window
7. control panel of the boiler control unit
8. fuel store feeder
9. fuel overflow
10. rotary burner
11. boiler body door
12. throttle flap lever
13. boiler body lid
14. heating water outlet
15. boiler flue outlet
16. manufacturer’s label
17. boiler control unit distribution board
18. emergency thermostat
19. boiler body
20. drain valve outlet
21. heating water inlet
9
8
7
4
6
3
2
1
19
18
16
17
15
14
13
5
10
11
20
21
12

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Fig 2 Front and rear view of BENEKOV K20 and K25 boilers
1. fuel store lid
2. fuel store
3. chain to secure the feeder
4. store feeder drive
5. control panel of the boiler control unit
6. fuel store feeder
7. fuel overflow
8. throttle flap lever
9. throttle flap locking bolt
10. rotary burner
11. boiler body door
12. boiler body lid
13. manufacturer’s label
14. heating water outlet
15. boiler flue outlet
16. boiler control unit distribution board
17. emergency thermostat
18. boiler body
19. drain valve outlet
20. heating water inlet
9
8
7
4
6
3
2
1
19
18
16
17
15
14
13
5
10
11
20
12

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Fig 3 BENEKOV K14 boiler basic dimensions

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Fig 4 BENEKOV K20 and K25 boiler dimensions

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4.2. Burner description
The burner is designed to burn solid fuel in the form of pellets. These must meet exact requirements - see
chap. 3. Burner operation is automatic and does not normally require supervision. The system of the
refractory rotary furnace prevents the slag, one of the components of the burning process, to adhere to it. By
rotating the furnace the ash and slag are moved forward until they are completely removed from the burner.
As the adhesion is eliminated the burner cleaning process is easier and the service life of the burner is
significantly prolonged.. The burning fuel is aerated and stirred along the furnace which intensifies the burning
process and enables perfect combustion of the delivered fuel.
The burner has a very low power consumption.
In cooperation with the modern programmer the burner is equipped with a safety device which interrupts the
fuel supply in the event of system overheating, flame loss in the furnace or fan failure. When the power
supply is interrupted the fuel feed is automatically switched off so the fuel that remains in the furnace does
not cause damage to the burner.
4.3. Burner operation
The operation of the burner starts by supplying the fuel from the store (9) via a screw feeder (8) connected to
the burner itself by means of a flexible hose (7) and a connecting elbow (6). Subsequently, the fuel dose is
moved by the screw feeder in the burner (12) into the rotary furnace (1). After there is sufficient supply of the
fuel to the burner ignition by a coil (13) follows. After the ignition the burner switches to normal operation
mode according to pre-set parameters. The air necessary to burn the fuel is supplied via the fan (10) through
the aeration chamber (2) to the rotary furnace (1) and a certain amount of air flows through the chamber (5)
onto the ignition coil (13). The air inlet to the burner is located at the bottom of the burner. During the
operation of the burner a mechanism (11) rotates the furnace (1) and the aeration chamber (2). The rotation
speed is adjustable. The combustion residue is moved to the front of the burner where it falls into the boiler
ash drawer.
Fig 5 Basic view of the rotary burner

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kde: 1 –rotary burner
2 –rotary aeration chamber
3 –insulation
4 –bearing
5 –aeration chamber
6 –connecting elbow to the fuel feed
7 –fuel overflow (flexible hose)
8 –screw feeder from the fuel store
9 –fuel store
10 –fan
11 –burner rotation mechanism
12 –screw fuel feeder in the burner
13 –ignition coil
The burner operation is fully automatic and adjustable. The fuel is dispensed from the fuel store depending
on the desired heat output. When the set temperatures are reached the burner automatically goes through
controlled extinguishing and goes into standby mode. Switching from stand-by mode to ignition mode is also
fully automatic.
The user therefore only needs to set the parameters correctly, replenish required fuel amount and remove
ash from the ash drawer.
Fig 6 Feeder and burner scheme

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4.4. Operation, control and safety features of the boiler
Boiler operation and control is provided by programmer –see separate user’s instructions.
Safety features, which ensure safe operation of the boiler:
•Emergency thermostat is used to prevent the heating system against overheating. It is set by the
manufacturer to a temperature of about 95 to 100 ° C which is higher than the desired boiler
temperature. The emergency thermostat is located on the back wall of the boiler in the distribution board
of the programmer.
•Throttle flap is located between the second and third levels at the top of the fin plate heat exchanger
and is used to control the temperature of flue gases at the boiler outlet.
Boiler K14:
When operating the boiler where the temperature of the flue gases is above 100 ° C, the throttle
flap must be closed which means the flap lever on the top of the boiler must be moved as far back
as possible and secured with the locking bolt. At the beginning of the boiler operation (when the
chimney is cold) or during long-term operation of the boiler at lower output it is recommended to
operate the boiler with a partially open flap so that the temperature of the flue gases does not drop
below 90 ° C. In this case the throttle lever must be moved forward and secured by the locking
bolt.
Boilers K20 and K25:
When operating the boiler where the temperature of the flue gases is above 100 ° C, the throttle
flap must be closed which means the flap lever on the side of the boiler must be turned as far as
possible upwards (forwards) and secured by the locking bolt At the beginning of the boiler
operation (when the chimney is cold) or during long-term operation of the boiler at lower output, it
is recommended to operate the boiler with a partially open flap so that the temperature of the flue
gases does not drop below 90 ° C. In this case the throttle lever must be rotated downwards
(backwards) and secured by the locking bolt.
•Optical sensor (photodiode) detects the presence of the flame in the furnace. If there isn’t enough
flame in the furnace, the programmer starts automatic ignition, i.e. it will deliver a small amount of fuel to
the burner and the ignition spiral is activated. The ignition mode lasts for about 2 to 3 minutes and then
the boiler goes into normal operation mode. However, if the ignition does not occur, the whole process is
repeated (3 attempts in total). After an unsuccessful ignition a corresponding alarm appears on the
display of the programmer, and the burner will not work further until the fault is rectified.
•Fuel feeder temperature sensor is located in the aerial chamber of the burner. In the event the fuel
burns through inside the screw feeder in the burner, the programmer interrupts the fuel supply from the
fuel store. This sensor is activated at the temperature of 60 ° C. This is a non-returnable alarm that can
only be removed by the user.
•Fuel overflow is another safeguarding feature against the fuel burning through into the fuel store. This
is a design where both screw feeders (the feeder from the store and the feeder in the burner) are
connected by a fusible flexible hose and a connecting elbow. This creates an air gap in the fuel feed
path between the burner and the store which protects the fuel in the store against the ignition.

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•The Hall probe is a part of the fan and it detects its revolutions. If there is an unscheduled stop of the
fan the programmer immediately interrupts the fuel supply from the store. This is a non-returnable alarm
that can only be removed by the user.
4.5. Boiler accessories
Standard accessories:
•the boiler operating and installation manual which includes the Warranty Certificate
•operating instructions for the boiler programmer
•addendum to the BENEKOV boiler operating and installation instructions - Installing the fuel store for the
BENEKOV K14, K20 and K25 boilers
•list of contractual service organizations
•ceramic parts - see chap. 6.2.
•ash drawer
•cleaning rake
Optional accessories:
•Boiler remote control with ecoSTER200 room panel function
Optional accessories are not included in the basic price of the boiler!
5. Boiler placement and installation
5.1. Regulations and directives
The solid fuel boiler may only be installed by a company with valid installation licence.
The heating project must be designed in accordance with valid regulations.
The heating system must be filled with water that meets the requirements of ČSN 07 7401: 1992; in particular
the hardness of the water must not exceed the required parameters.
Chart 4 Heating water parameters
Parameter
Unit
Value
Hardness
mmol/l
1
Ca2+
mmol/l
0,3
Fe + Mg total concentration
mg/l
0,3 (recommended value)
Regulation and directive relating to:
A) heating circuit
ČSN EN 303-5:2013 Boilers for central heating - Part 5: Boilers for central heating using solid
fuels, with manual or automatic delivery, with a rated thermal output not
exceeding 500 kW - Terminology, requirements, testing and marking
ČSN 06 0310:2014 Heat systems in buildings –Design and Installation
ČSN 06 0830:2014 Heat systems in buildings –Safety devices
ČSN 07 7401:1992 Water and steam for thermal power equipment with working pressure up to 8
MPa
B) chimney

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ČSN 73 4201:2010 Chimneys and flues - Design, implementation and connection of fuel
appliances
C) fire regulations
ČSN 06 1008:1997 Fire safety of thermal equipment
ČSN EN 13 501-1+A1:2010 Fire classification of construction products and building structures - Part 1:
Classification according to the results of reaction to fire tests
D) power supply
ČSN 33 0165: 1992 Electro technical regulations. Colour or number wire markings.
Implementation regulations
ČSN 33 1500: 1990 Electro technical regulations. Inspection of electrical equipment
ČSN 33 2000-1 ed.2: 2009 Low voltage electrical installations - Part 1: Basic aspects, determination of
basic characteristics, definitions
ČSN 33 2000-4-41 ed.2: 2007 Low voltage electrical installations - Part 4-41: Safety precautions -
Protection against electric shock
ČSN 33 2000-5-51 ed.3: 2010 Building electrical installations - Part 5-51: Selection and construction of
electrical equipment - General regulations
ČSN 33 2000-7-701 ed.2:2007 Low voltage electrical installations - Part 7-701: Single-purpose and special-
purpose appliances - Areas with bath or shower
ČSN 33 2030:2014 Electrostatics - Static electricity elimination directive
ČSN 33 2130 ed.2:2009 Low voltage electrical installations –Internal electrical wiring
ČSN 33 2180:1979 Electro technical regulations ČSN. Connecting electrical devices and
appliances
ČSN 33 2350:1982 Electro technical regulations. Regulations for electrical installations in difficult
climatic conditions
ČSN 34 0350 ed.2:2009 Safety requirements for mobile leads and cords
ČSN EN 55 014-1 ed.3:2007 Electromagnetic compatibility - Requirements for household appliances,
power tools and similar appliances - Part 1: Emissions
ČSN EN 55 014-2:1998 Electromagnetic compatibility - Requirements for household appliances,
power tools and similar appliances - Part 2: Resistance –The standard of the
group of appliances
ČSN EN 60079-14 ed.3:2009 Explosive atmospheres - Part 14: Design, selection and installation of
electrical systems
ČSN EN 60335-1 ed.2:2003 Household and similar electrical appliances - Safety - Part 1: General
requirements
ČSN EN 60335-2-102:2007 Household and similar electrical appliances - Safety - Part 2-102: Particular
requirements for appliances burning gaseous, petroleum and solid fuels
containing electrical connections
ČSN EN 60445 ed.4:2011 Basic and safety principles for human-machine interface, marking and
identification - Colour or letters and number wire markings
ČSN EN 61000-3-2 ed.3:2006 Electromagnetic compatibility (EMC) - Part 3-2: Limits - Limits for harmonic
current emissions of devices with input phase current <= 16 A
ČSN EN 61000-3-3 ed.2:2009 Electromagnetic compatibility (EMC) - Part 3-3: Limits - Limitation of voltage,
voltage fluctuation and flicker changes in low voltage distribution systems for
rated phase current <= 16 A which is not subject to a conditional connection
E) noise
ČSN EN ISO 3746:2011 Acoustics - Determination of acoustic power levels and sound power levels of
noise sources by means of acoustic pressure - Operation method with
ČSN EN ISO 11202:2010 Acoustics - Noise emitted by machinery and equipment - Determination of
emission sound pressure levels at the operator's station and other specified
locations using approximate environmental corrections

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F) machinery
CSN EN 614-1 + A1: 2009 Safety of machinery - Ergonomic design principles - Part 1: Terminology and
general principles
ČSN EN 953 + A1: 2009 Safety of machinery - Protective covers - General requirements for the
construction and manufacture of fixed and movable guards
EN 1037 + A1: 2008 Safety of machinery - Prevention of unexpected start-up
ISO 12100: 2011 Safety of machinery - Basic concepts, general principles for construction
ISO 13857: 2008 Safety of machinery - Safe distances to prevent reach of dangerous places
by upper and lower limbs
5.2. Boiler location options
Boiler location in regards to the electric supply:
•the boiler must be positioned so the plug in the socket (230V / 50Hz) is always accessible.
•the boiler needs to be always connected to the mains by a flexible secure lead with a standardized plug.
•protection against electric shock (including earth connection of individual metal parts) must be ensured in
accordance with valid regulations ČSN EN (see chapter 5.1.)
Boiler location in regards to fire regulations:
1. Location on a base made of non-flammable material
•Place the boiler on a non-flammable heat insulating mat which exceeds the size of the boiler by 20
mm on each side.
•If the boiler is located in a basement it is recommended to place it on a structure at least 50 mm high
off the floor level. The boiler must be positioned horizontally.
2. Safe distance from flammable materials
•The smallest permissible distance of the external contours of the boiler and the smoke flue from any
flammable materials (see more specifications in ČSN EN 13 501-1 + A1: 2010) is 400 mm during
installation as well as during the operation of the boiler.

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Fig 7 Position of the K14 boiler in a boiler room

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Boiler location in regards to required handling space:
•AA5 / AB5 basic setting rating according to ČSN 33 2000-1 ed.2:2009
•minimum of 600 mm handling space must be left in front of the boiler (applies for K14 boiler) and 1000
mm (applies for K20 and K25 boilers)
•minimum distance between the back of the boiler and the wall must be 400 mm
•minimum 500 mm clearance on the side of the boiler body (applies for K20 and K25 boilers) to enable
cleaning of the exchanger convection surface
•minimum 500 mm clearance on the side of the fuel store to enable easy replenishment
•minimum 350 mm clearance above the fuel store to enable easy replenishment
Fuel store installation and positioning:
•To install the fuel store to the K14, K20 and K25 boilers follow separate appendix to BENEKOV boiler
operating and installation instructions.
•The fuel store must be, in regards to the boiler body, positioned in such way as to ensure reliable fuel
overflow without the risk of clogging the flexible hose. The flexible hose can be shortened accordingly.
•The angle of inclination between the feeder and the horizontal floor must be between 0 and 60 °, the
optimal inclinatoin is 45 °.
Fuel location:
•It is recommended to store the pellets in a dry place in their original manufacturer’s packaging (PET bags
or „big bags“).
•The pellets must not be stored behind the boiler or next to the boiler at a distance of less than 400 mm.
•The manufacturer recommends keeping the distance between the boiler and the fuel to a minimum of
1 000 mm or place the fuel in a room separate to where the boiler is located.
Fig 8 Position of the K20 or K25 boiler in a boiler room

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Permanent supply and drawing of air to enable the burning and ventilation must be provided to the room
which the boiler is installed into.
Air consumption at rated output for:
- BENEKOV K14 boiler is approximately 45 m3. hr-1
- BENEKOV K20 boiler is approximately 55 m3. hr-1
- BENEKOV K25 boiler is approximately 75 m3. hr-1
Only qualified personnel are allowed to carry out the connection of the heating system pipework or the
internal heating element.
WARNING: When connecting the boiler to the heating system, the drain valve must be located at
the lowest point and as close to the boiler as possible.
5.3. Connection to the chimney
The chimney cross-section shall not be less than 200 cm2.
Extraction by a flue pipe that is only secured in the flue and attached to the extraction outlet must be of
secure construction in order to prevent accidental or spontaneous disconnection of the pipes.
Should the extraction be longer than 2 m it must be secured. The flue pipe must be made of non-flammable
materials.
It is recommended that any leaks in the flue pipe (seams) are sealed with a sealant designed for this purpose
or covered by aluminium tape.
It is recommended that the chimney vents are sufficiently heat-insulated and protected from getting cold. This
can be ensured by suitable positioning within the building. If chimney is cooled too much it must be lined in
such a way as to prevent condensation of the vapours contained in the cooled flue gases and subsequent
absorption of the condensate into the chimney structure.
It is not recommended to have the flue pipe longer than 1 m. The cooling of the flue gases occurs in the part
which is not insulated. Furthermore, if the boiler runs at low output the condensation of the moisture in the
flue gasses could occur.
The connection of the boiler to the chimney must be carried out in compliance with the requirements set in
ČSN 73 4201:2010 Chimneys and flue pipes.
•Connect BENEKOV K14 boiler to the chimney by a metal pipe with a diameter of 118 or 120 mm.
•Connect BENEKOV K20 and K25 boilers to the chimney by a metal pipe with a diameter of 145 or 150
mm.
6. Commissioning the boiler - for contractual service companies
The commissioning of the boiler may only be carried out by a contractual service companies
authorized to carry out this activity.

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6.1. Connection dimensions
Fig 9 BENEKOV K14 boiler connection dimensions
Fig 10 BENEKOV K20 and K25 boilers connection dimensions