Cerbos UNI User manual

UNI
Cast-iron solid fuel boiler
Installation and
operating instructions
Rev. June 2010

Content:
1. Introduction
2. Characteristics of boilers
3. Technical para eters
4. Delivery and accessories
5. Location and installation
5.1. Regulations and directions
5.2. Location options
5.3. Installation into the heating syste
5.4. Surplus heat re oval equip ent
5.5. Chi ney connector
5.6. Installation procedure
6. Operating instructions
6.1. Putting into operation – instructions for a specialized service organization
6.2. Putting the boiler into operation
6.3. Firing
6.4. Operation
6.5. Fuel
7. Maintenance and cleaning
7.1. Maintenance
7.2. Regular inspections
7.3. Boiler cleaning
7.4. Annual inspection
8. Health and safety infor ation
9. I portant warnings
10. Guidelines on the product end-of-life disposal
11. Warranty and liability for defects
12. Certificate of warranty

1. INTRODUCTION
Thank you for buying the boiler UNI. Please read carefully this anual before installing and putting the product into
operation and keep it during the whole ti e of its service life. Do not touch or intervene in any parts of the product
unless it is explicitly allowed. The installation, aintenance and service of this boiler can be perfor ed only by
technicians of a specialized service agency. This anual as well as necessary regulations have to be observed when
installing the boiler and specifying its correct location, at establishing the water connection and structuring the
chi ney.
2. CHARACTERISTICS OF BOILERS
The UNI boiler is a cast-iron sectional boiler for burning solid fuels with three-draught design. It is intended for hot-
water heating of single fa ily houses and other objects.
The three-draught boiler design enables to achieve a high efficiency and low e ission values. The boiler can be used
both in gravity central heating syste s and syste s with forced circulation.
The boiler burns wood and black coal – fuel specifications are given further in this anual. Because the heating
powers of single solid fuels differ fro each other, the boiler output varies between the stated axi u and
ini u values. Coke can be utilized as an alternative fuel.
3. Technic al para eters
Model UNI 3 UNI 4 UNI 5 UNI 6 UNI 7 UNI 8
Nu ber of sectional boiler ele ents 3 4 5 6 7 8
Fuels Wooden logs, black coal
Output range kW 13 –
16.5 19.5 – 20 24 - 28 27 - 35 30.5 - 44 33.8 – 53
Weight kg 190 235 280 325 370 415
Water volu e l 22 28 34 40 46 52
Co bustion cha ber volu e d 3 33.0 51.6 70.3 89.1 107.8 126.5
Maxi u height of the loaded fuel 280
Heating water service te perature range °C 60 up to 90
Mini u return water te perature °C 60 (reco ended)
Safety syste activated at °C 95
Maxi u service pressure bar 3
Flue gas outlet dia eter 160
Water inlet/outlet connections 2"
Height (H2) 1 070
Width (A) 520
Length (L) 432 537 642 747 852 957
Fuel type Wooden logs
Output kW 13 19.5 24 27 30.5 33.8
Efficiency % 62-67,5
Boiler class 1
Maxi u loading co bustion ti e h 2 up to 4
Required fuel para eters Maxi u water content 20%
Reco ended cross-section 10 c x 10 c
Average calorific value 14 – 18 MJ/kg
Flue gas average te perature °C 220 - 300
Required chi ney draught bar 0.15-0.2 0.15-0.22 0.15-0.25 0.15-0.26 0.15-0.27 0.15-0.28
Boiler hydraulic loss at Δt=20 °C bar 0.13 0.51 1.03 1.81 2.92 4.63
Average CO content at %10 O₂ g/ ³ 8 500 – 10 800
Fuel type Black coal
Output kW 16.5 20 28 35 44 53
Efficiency % 70.6 – 76.6
Boiler class . 2
Maxi u loading co bustion ti e h 4 up to 6
Required fuel para eters Maxi u water content 15%
Reco ended size between 30 up to 60
Average calorific value 26 – 28 MJ/kg
Flue gas average te perature °C 220 - 320
Required chi ney draught bar 0.15-0.2 0.15-0.22 0.15-0.25 0.15-0.26 0.15-0.27 0.15-0.28
Boiler hydraulic loss at Δt=20 °C bar 0.24 0.76 1.46 2.47 3.90 5.84
Average CO content at %10 O₂ g/ ³ 4900 - 7400

Opening to connect the discharge valve R ½“
Figure No. 1 – Boiler sche atic illustration
4. Delivery and accessories
The UNI boiler is delivered as follows: co plete boiler dru and cardboard package containing the boiler shell and
insulation are placed side by side on a palette while boiler accessories are inserted inside the boiler dru . The boiler
ust not turn over during the transportation.
Accessories delivered regularly together with the boiler:
Draught controller
Suspension plate
Cleaning brush
Scraper
Fire hook
Ther o ano eter ( ounted on the boiler shell upper cover)
Obligatory accessories for closed heating systems:
Two-way safety valve DBV 1 - 02 .
This equipment may not be used in the case of open heating systems.
4.1 Delivery and accessories
tandard boiler delivery:
• Boiler on the palette
• Shell in the cardboard package including insulation
•Ashtray (inside the boiler drum)
• leaning tools (cleaning brush, scraper, fire hook)
• Thermomanometer (mounted on the boiler shell upper cover) (1 piece)
• Filling and discharge cock Js 1/2“ (1 piece)(mounted on the boiler drum)
• Draught controller (1 piece)
• Smoke flap control label (1 piece)
• Shell connection accessories (in the shell cardboard package)
• Heating and return water flange 2“ (2 pieces); (mounted on the boiler drum)
• ommercial and technical documentation
Essential accessories: (not included within the delivery)
• Two-way safety valve DBV 1 – 02. This equipment may not be used in the case of open heating systems.
• Safety valve (1 piece)
At customer’s request: (not included within the delivery)
• Filter 3/4“ (for a boiler equipped with the two-way safety valve DBV 1 – 02)
The boiler equipment ordered as “essential accessories and at customer’s request” is not included within the basic
boiler price.
5. Location and installation
5.1 Regulations and directions

The solid fuel boiler can be installed only by a specialized company validly authorized to execute its installation and
maintenance. An installation project according to applicable regulations is required. Before installing the boiler onto
an older heating system, the installation company has to rinse out (clean up) the whole system. The heating system
must be filled with water corresponding to Č N 07 7401 and especially its hardness cannot exceed the required
parameters.
In case the two-way safety device reacts adding the water that does not comply with Č N 077401, it is necessary to
treat the water inside the system so that it meets again requirements of this standard.
a) To the heating system
ČSN 06 0310 Heating systems in buildings – Designing and installation.
ČSN 06 0830 Heating systems in buildings – Protecting equipment.
ČSN 07 7401 Water and steam for thermal energy devices with operating steam pressure up to 8 Mpa.
ČSN EN 303–5 Boilers for central heating systems – Part 5: entral heating solid fuel boiler with manual or automatic
fuel supply and maximum nominal output of 300 kW – terminology, requirements, testing and marking.
b) To the chimney
ČSN 73 4201 Designing of chimneys and smoke stacks.
c) With regards to fire regulations
ČSN 06 1008 Fire safety of heat installations.
ČSN EN 13 501-1 Fire-technical material properties. Building material combustibility grades.
d) To the system for TUV heating
ČSN 06 0320 Heating systems in buildings – Hot water preparation – Designing and projection.
ČSN 06 0830 Heating systems in buildings – Protecting equipment.
ČSN 73 6660 Water distribution pipes.
5. 2. Location o tions
The UNI boiler ust be installed in a separate boiler-roo specifically odified for heating purposes. The boiler-
roo area should be sufficient to enable the boiler installation and aintenance. It ust be secured a satisfactory
fresh air circulation for the co bustion process. The chi ney structure ust ensure the appropriate draught with
regards to the respective boiler type and ust eet the building criteria entioned further in this anual and
binding regulations. You can never install the boiler within open spaces or terraces, inside pre ises inhabited by
people as kitchens, living roo s, bathroo s, bedroo s or in areas where explosive or fla able aterials are
stored.
It is reco ended to install the boiler onto a fire-proof concrete base. The base ini u di ensions are stated
within the following table:
Model UNI 3 UNI 4 UNI 5 UNI 6 UNI 7 UNI 8
Base height ( ) 50
Base width ( ) 600
Base length ( ) 385 490 595 700 805 910
Free space
The below-indicated ini u free space should be available around the boiler.
Figure No. 2 – Free space

Safety distance from flammable materials
− When installing and operating the boiler, it is necessary to observe the safety distance of 200 mm from flammable
materials with B, 1 and 2 combustibility grades (according to ČSN 06 1008).
− Regarding easily flammable materials with 3 combustibility grade that burn quickly and alone even after the
ignition source has been removed (e.g. paper pasteboard, cardboard, asphalt and tar pasteboards, wood and wood-
fibre boards, plastics, flooring materials), the safety distance must be doubled to 400 mm.
− The safety distance must be also doubled if the building material combustibility grade has not been proven.
The boiler location with regards to the necessary handling space:
− Basic environment AA5/AB5 according to ČSN 33 2000-3.
− Minimum handling space of 1000 mm should be reserved in front of the boiler.
− Minimum distance between the rear boiler part and wall makes 600 mm.
− Minimum space of 400 mm for accessing the rear boiler part must be reserved from one side at least.
Combustibility grades of building materials and products
ombustibility grades of
building materials and
products
Building materials and products classified according to their combustibility grade
(selection from ČSN EN 13 501-1)
A – nonflammable
B – hardly flammable
C1 – heavily flammable
C2 – moderately
flammable
C3 – easily flammable
granite, sandstone, concrete, bricks, ceramic tiles, mortars, fire-stopping plasters,…
akumin, izumin, heraklit, lignos, basalt plates and felts, fibre-glass boards,…
beech wood, oak wood, hobrex plates, plywoods, werzalit, formica, sirkolit,…
pine wood, larch wood, spruce wood, chipboard and cork slabs, rubber flooring
materials,...
asphalt pasteboards, pressed fibre-boards, cellulose materials, polyurethan, styrofoam,
polyethylene, PV ,…
Fuel location:
− It is strictly forbidden to place the fuel behind the boiler or store it next to the boiler within a distance smaller than
800 mm.
− It is strictly forbidden to place the fuel between two boilers in the boiler-room.
− The producer recommends to keep the minimum distance of 1000 mm between the boiler and fuel or place the fuel
into a room being separated from the room where the boiler has been installed.
5. 3 Installation into the heating system
The rotecting equi ment against overheating is not necessary in the event of using an o en ex ansion reservoir.
Any heat source within the open ther al syste ust be connected to the open expansion reservoir being located in
the highest ther al syste point. The expansion reservoirs ust be di ensioned so that they are able to take hold
of water volu e changes incurred by heating and cooling processes. These open expansion reservoirs have to be
equipped with non-shuttable aeration and overflow pipelines. The overflow pipeline should be designed in order to
drain off safely the highest flow quantity entering the syste . This can be reached through di ensioning the
overflow pipeline by one DN higher than the filling pipeline. The expansion reservoirs and respective connection
pipelines ust be designed and positioned so that their freezing is reliably prevented.

1 Heat source
2 Expansion reservoir
3 Protecting pipeline
4 Expansion pipeline
5 Overflow pipeline
6 Filling pipeline
7 Water level li iter
8 Return pipeline
Figure No. 3 – Exa ples of connecting the open expansion reservoirs
5.4. Sur lus heat removal equi ment
The two-way safety valve DBV 1 - 02 serves for removing the sur lus heat in case the boiler water tem erature
exceeds 95°C. This two-way safety valve is connected to boiler flanges as shown in the figure No. 5. If the syste is
fitted with the two-way safety valve DBV 1 – 02 and the boiler beco es overheated (inco ing water te perature is
higher than 95°C), the two-way safety valve creates a cold water cycle until the te perature decreases below the
li it value. At this o ent, the discharge cooling equip ent and inlet of cold water being added into the syste are
closed si ultaneously.
Figure No. 4 – Two-way safety valve DVB 1 - 02

1 – Boiler
2 – Two-way safety valve DBV 1 – 02
3 – Protection valve
4 – Reduction valve
5 – Filter
6 – Ball cock
7 – Pu p
8 – Surplus heat re oval
9 – Draining cock
I – Cold water inlet
II – Heating water outlet
III – Return water inlet
Figure No. 5 – Reco ended sche e of connecting the two-way safety valve DBV 1 - 02
Technical data of the two-way safety valve DBV 1 – 02 (manufactured by the com any Regulus)
Opening te perature (li it value): 100°C (+0°/- 5°C)
Maxi u te perature: 120°C
Maxi u pressure on the boiler part: 300 kPa
Maxi u pressure on the water part: 600 kPa
No inal flow at delta p = 100 kPa: 1.9 3/h
A lication
The two-way safety valve DBV 1 – 02 is intended to protect the central heating boilers against overheating. The
draining and filling valve inside the valve body is controlled by a ther ostatic ele ent. When the li it te perature is
reached, draining and filling valves are opened si ultaneously which eans that the cold water flows into the boiler
while the hot water is drained off. When the te perature drops below the li it value, draining and filling valves are
closed at the sa e ti e.
ATTENTION! This does not su ersede the rotection valve.
In case the two-way safety device reacts adding the water that does not com ly with ČSN 077401, it is necessary to
treat the water inside the system so that it meets again requirements of this standard.
Installation
The installation can be perfor ed only by a professionally co petent person. In order to secure a correct function of
the ther ostatic two-way safety valve, it is necessary to adhere to specified conditions of its installation and respect
the flow direction arking on the valve body. The safety valve should be always ounted into the outlet boiler
pipeline or directly onto the boiler in its upper part where the heated water leaves the boiler being distributed into
the heating syste . When attaching the valve, it is essential to check whether the usage of 3/4“ sleeve piece – that
can be ounted either inside the pipeline or on the boiler – ensures a full sub ersion of the ther ostatic valve
ele ent following the valve installation. After ounting into the sleeve piece, the discharge conduit draining the hot
water fro the boiler shall be connected at the point “C” (figure No. 4). The inlet of cold water (according to the
figure No. 5) that ensures the boiler cooling after the valve is put into operation shall be connected at the point “A”
(figure No. 4). A filter for retaining echanical i purities ust be fitted onto the cooling water inlet. At the point
“B”(figure No. 4), a conduit shall be attached leading into the heating syste reverse pipe in the boiler vicinity
(according to the figure No. 5).
Regular maintenance

Turn the safety valve head once a year to re ove pertinent i purities for ed inside the valve. Clean up the filter
fitted on the cooling water inlet.
Heat removal equi ment – storage reservoirs
It is reco ended to install a storage reservoir in case the required volu e exceeds 300 litres.
A calculation of the stack exchanger s allest volu e:
Vsp = 15Tb x QN (1-0,3 x (QH/Q in))
Where:
Vsp = storage reservoir volu e in litres
QN = no inal heat output in kW
Tb = burning ti e in hours
QH = building ther al load in kW
Qin = lowest heat output in kW
The storage reservoir di ensions at central heating boilers operated with single specified fuels ust be deter ined
according to the output of the largest storage reservoir. However, this storage reservoir is not necessary if the
calculated volu e is s aller than 300 l.
5. 5. Chi ney connector
The UNI boiler ust be connected to an independent chi ney ensuring at least the required ini u draught. The
s oke stack between the boiler and chi ney should be insulated with ineral wool. The s oke stack leading to the
chi ney and chi ney itself ust be ade out of steel or equivalent aterial which ay be used at te peratures
around 400°C. All joints of the exhausting syste ust be sealed to enable a good burning and high efficiency. The
s oke stack ust be attached to the chi ney through the shortest way possible and shall co ply with di ensions
stated within the subsequent sche e. Any horizontal connections and equip ent increasing the pressure losses, as
bends, have to be excluded.
A co pact vertical steel pipeline should not be used as the
chi ney. The chi ney ust consist of one inner and one outer
layer. The outer layer can be ade out of steel or bricks.
Regarding the inner layer, stainless steel parts are preferred
because of corrosion. The space between the inner and outer
layer ust be insulated in order to prevent the condensation in
flue gases.
A cleaning hole ade out of steel and sealed against a possible
leakage should be prepared at the lowest chi ney level.
The s oke stack length between the boiler and chi ney should
not exceed 100 c .
The chi ney dia eter ust be by 10% larger than the s oke
stack dia eter on the boiler. As regards the chi ney
total height
and ini u inner dia eter, the following sche e
should be
taken into account with reference to the boiler
output unless
stated otherwise within respective binding
regulations.
Figure No. 6 – Exa ple of the
chi ney connection

The highest outdoor chi ney level should be in co pliance with di ensions presented on the following sketch in
order to ini ize any har ful environ ental i pacts and i prove the chi ney draught.
Figure No. 7 – Deter ination of the chi ney dia eter
5.6 . INSTALLATION PROCEDURE
Boiler installation – in the closed heating system with the two-way safety valve DBV 1 - 02
1. Place the boiler drum onto a base wall (pad).
2. onnect the heating water flange to the heating system.
3. onnect the return water bottom flange to the heating system.
4. onnect the two-way safety valve DBV 1 – 02 (according to the figure No. 5) to the return heating water flange,
cooling water inlet and surplus heat outlet.
5. Put the smoke extension on the smoke pipe and insert into the chimney opening.
6. Screw the draught controller into the opening in the upper part of the front sectional boiler element. The procedure
of adjusting the boiler draught controller is presented within the manual enclosed to the respective controller.
hell installation
1. Remove shells from the cardboard package.
2. Put the left and right shell part on the anchoring screws and fix them to the boiler drum in the front part using
screws and nuts (right part with the aid of screws – 3 pieces, left part with the aid of nuts – 3 pieces; at the same
time, they serve for attaching the suspensions of feeding and ashtray doors.
3. The thermomanometer is already inserted in the upper shell part. Insert the temperature gauge into the
thermometer well located in the upper part of the front boiler drum sectional element and insert the pressure gauge
into the well of outgoing (heating) water flange. The pressure gauge capillary must not touch the boiler drum.
4. Install 4 pieces of fastening pins into the upper shell part. Put the upper cover onto side shell parts – insert the
fastening pins into prepared feathers.
5. Put the rear shell part on and bolt it to the side and upper shell parts with the aid of screws.

Filling the heating system with water
The water hardness must meet requirements of ČSN 07 7401 – if it be to the contrary, treat the water as given in
the cha ter No. 5.1.
Heating systems fitted with the o en ex ansion reservoir enable a direct contact of the heating water with
atmos here. In the course of heating eriod, the water ex anding in the reservoir absorbs oxygen which enhances
its corrosive effects and, at the same time, eva orates significantly. For refilling the system, only water treated
onto values com lying with ČSN 07 7401 can be used.
The heating syste ust be thoroughly rinsed to re ove all i purities. It is necessary to aintain a stable water
volu e in the heating syste during the course of heating period. When adding water into the heating syste , it is
inevitable to look out for preventing any air induction into the syste . Water fro the boiler and heating syste
ust never be drained or taken at disposal except for cases indispensably needed, e.g. in the event of repairs etc. A
drainage and filling of new water increase the danger of corrosion and scale for ing. If it is necessary to refill water
into the heating system, add it only into a chilled boiler in order to avoid disru tions of sectional boiler elements.
After filling the boiler and heating system, it is essential to check the tightness of all joints. When using the two-
way safety valve DBV 1 – 02, the cooling water is added gradually into return water.
The ter ination of installation and heating test execution ust be recorded in the “Certificate of warranty”.
6. OPERATING INSTRUCTIONS
6.1 . Putting into operation – instructions for a specialized service organization
The boiler can be put into operation only by specialized installation companies entitled to performing all respective
activities.
Inspection activities before the start-up
Before putting the boiler into operation, it is necessary to check:
a) Filling the heating system with water (check of the thermomanometer) and system tightness.
b) onnection to the chimney – this connection can be done only upon approval of the respective chimney company
(chimney revision).
c) Functionality of the draught controller and thermostatic valve.
6.2. Putting the boiler into operation
1. Fire the boiler.
2. Set the boiler to the needed service temperature – recommended temperature of the outgoing water is 80° .
3. Adjust the draught controller including the chain length (in accordance with the enclosed draught controller
instructions).
4. heck the functionality of safety equipment against overheating (two-way safety valve DBV 1 - 02).
5. Run the boiler under operating conditions in compliance with respective standards.
6. Recheck the boiler tightness.
7. Inform the user how to operate the boiler.
8. Make entry into the certificate of warranty.
6.3. Firing
1. heck the amount of water inside the heating system using the thermomanometer.
2. Open the shutting armatures between the boiler and heating system.
3. heck whether the chimney draught as regards the connected product is sufficient.
4. lean up the fire grate, ashtray, smoke stacks and boiler walls.
5. Open the ashtray and flue gas chamber doors. Lay the kindling and wood onto the cleaned fire grate along the
whole boiler depth.
6. Put the smoke flap inside the smoke extension to the position “open” and close the auxiliary air inlet of the feeding
door.
7. Fire the kindling through the open combustion chamber door and close it subsequently.
8.The ashtray door should remain opened until the kindling fires perfectly. It is recommended to lay another weaker
layer of the basic fuel onto the burning kindling.
9. lose the ashtray door after it fires well – add further fuel through the feeding door up to its lower edge and align
the fuel into an even layer along the whole boiler depth.
10. Set the primary air supply using the draught controller after closing the ashtray door – recommended
temperature adjustment makes at least 70° .
11. As soon as the fuel merges into deep red glow, open slightly the auxiliary air inlet in the feeding door.

6.4. Operation
1. After reaching the heating water temperature, adjust the supply of combustion air. The boiler output can be
roughly regulated by changing the chimney draught with the aid of smoke flap inside the smoke extension. A fine
output regulation is achieved by using the auxiliary air choker that adjusts the air supply under the fire grate through
the draught controller. Set up the draught controller so that the ashtray door choker is almost closed when the
required heating water temperature has been reached.
2. During the operation, the boiler must be refueled depending on the heat requirements and combustion intensity.
Feed the fuel so that the fuel layer is evenly high along the whole boiler depth. The fuel should be added up to the
maximum height of 2 cm below the bottom margin of feeding space opening.
3. When burning black coal or wood, it is necessary to keep slightly open the auxiliary air inlet of the feeding door all
the time during which the gases and flames from the freshly fed fuel are evolving. If adding any new fuel, open
slightly the feeding door by about 2 cm and wait for 10 seconds approximately until the flue gases are exhausted into
the chimney. Afterwards, you may open the door completely.
4. When changing over to the lowered night service, clean up the fire grate, let the freshly fed fuel burn up well and
then suppress the boiler output by choking the chimney draught with the aid of smoke flap located in the smoke
extension and closing the auxiliary air inlet flap in the feeding door. It is always necessary to prevent any leakage of
flue gases into the area of boiler-room. If a leakage occurs, the draught controller must be totally inactivated (close
the choker completely).
5. In the morning, recover the boiler operation by unclosing the smoke flap and raking up the fire grate after the
ashtray door is opened.
6. Ashtray door must be permanently closed during the boiler operation.
7. Empty the ashtray according to needs (it is necessary to use gloves).
8. When using shut-off valves, it is necessary to install the protection valve between the boiler and shut-off valve.
9. It is recommended to clean up the filter after the heating test is finished and subsequently before starting the
heating period.
Figure No. 8 – Auxiliary air choker
Suspension plate
UNI is a three-draught boiler. It is equipped with a suspension plate (50) on the boiler front sectional ele ent to
avoid leakage of flue gases fro the boiler when the upper door is opened. The suspension plate also protects the
upper door against overheating.

Figure No. 9 – Suspension plate
You can lift the suspension plate when feeding a new fuel – however, keep it always in the right position to aintain
an efficient co bustion.
6.5. Fuel
The fuel ust eet the data presented within the section on technical para eters. The anufacturer does not bear
any liability for proble s caused by using fuels that are not suitable with respect to this boiler.
7. MAINTENANCE AND CLEANING
A regular aintenance perfor ed by skilled personnel in co pliance with the anufacturer’s instructions is
necessary for ensuring the effective syste operation.
7.1 . Maintenance
•Re ove ash fro the ashtray during the boiler operation several ti es a day depending on the used fuel
because the full ashtray prevents the correct distribution of co bustion air under the fuel and causes uneven
fire penetration of the fuel laid on the grate. Re ove all residues fro the co bustion cha ber, especially slag,
before any new firing and in the course of the orning recovery of boiler operation. The ash should be gathered
into non-fla able containers equipped with a cover. When working, use rotective means and pay attention
to your personal safety.
•While burning black coal or wood, clean up regularly the boiler walls inside the co bustion cha ber, boiler
s oke draughts and s oke extension (using a brush when the boiler is cooled down and te perature does not
exceeds 40°C) once a onth.
•When using fuels with larger evolution of gas and tar deposits conta inate the walls of co bustion area,
re ove the by burning dry and hard wood while putting the boiler onto the axi u service te perature.
•Attend properly the s oke flap swivels and pivots of all doors after the heating season is over.
7.2 . Regular ins ections
•In the case of open syste , check the water level inside the expansion reservoir. In the case of closed syste ,
deaerate the whole heating syste and adjust the syste water pressure according to the water colu n height
at axi u te perature of 40°C. If the water level or pressure is below the level of water colu n height after
the boiler is filled for the first ti e, it is necessary to supply additional water into the syste and deaerate it
again. The water to be added into the syste ust be treated in co pliance with local regulations (see the
chapter 5.1.) in order to avoid corrosion inside the heating circle and boiler. The water refilling into the heating
syste can be done only if the boiler is cold otherwise the cast-iron ele ents ay crack.
•Check the boiler front door whether the seal is functional. Replace the door gaskets where appropriate.
•Check the insulation condition inside the front door. If it is da aged, the front door surface te perature would
be higher. In this case, it is necessary to replace the insulation in order to save energy and prevent further
cracking.
•Check whether flue gases leak fro the chi ney connector and get it repaired if they do.

•Check the correct function of draught controller in the boiler upper part. In case of need, you can easily adjust
the controller to achieve better burning and output of your boiler. If the co bustion air a ount is not sufficient,
you ay observe an excessive soot deposition on heating surfaces and s oke evolution (or s ell). Set up the
flap of pri ary air so that larger air volu e is sucked in for ore efficient burning. If the co bustion air quantity
is redundant, solid fuels are consu ed quickly. In such a case, it is reco ended to reduce the air supply –
either by the pri ary air flap or s oke flap.
•Check the surfaces transferring the heat fro cast-iron ele ents. The soot for ation will vary in dependence on
the kind of fuel that you are using and co bustion air quantity. If you feel that the outgoing water te perature
cannot reach the usual value under the sa e conditions, it is reco ended to clean up the boiler heating
surfaces.
7.3 . Boiler cleaning
Before cleaning the boiler, switch off the pu p and other electrical appliances in the boiler-roo . Clean up the boiler
only when it is cooled.
When cleaning the boiler, re ove the suspension plate (50) shown in the figure No. 11.
When cleaning the boiler:
* Clean up all heating surfaces using the brush supplied together with the boiler.
* Clean up the flue gas routes using the supplied brush.
* Sweep the deposited soot down to the ashtray area.
* Re ove the waste.
Figure No. 10 – Procedure of re oving the suspension plate
Annual ins ection
Before any heating season, it is recommended to invite a re resentative of s ecialized service organization to
ins ect the condition of boiler, heating system, electrical connections and chimney. Do not attem t to erform
any maintenance work without assistance of qualified ersons.
8. HEALTH AND SAFETY INFORMATION
Sharp edges
Give attention when handling iron-plate panels having unsecured or sharp edges.
Pressure equip ent
1. Avoid contacts with pressure parts of the heating syste during the boiler operation. These dangerous parts are:
Boiler sectional ele ents
Boiler input and output conduit
Safety conduit
Pressure protection equip ent ounted on the heating syste
2. Never atte pt to drain water fro the heating syste while the boiler is operating.
3. Never, and by any reason, feed cold water directly into the boiler while it is operating and hot – if you do it, the
boiler sectional ele ents ay be da aged (cracks). When using the two-way safety valve DBV 1 – 02, the cooling
water is gradually added into return water.
High te perature surfaces
Avoid contacts with high te perature parts and surfaces being dangerous for hu ans as further indicated:
Boiler feeding door

Ashtray door in the front
Water input and output conduit (although it is insulated), safety conduit
S oke stack
Connector between the s oke stack outlet and chi ney
Circulating pu ps, expansion reservoirs
Boiler-roo
1. Make sure that the boiler-roo can be easily left in the case of e ergency related to the heating syste .
2. Do not leave the solid fuels and auxiliary aterial (kindling, paper, etc.) for firing the boiler within the distance
shorter than 800 fro the boiler.
3. Do not cover openings that supply fresh air into the boiler-roo because the air supply is very i portant for good
burning.
Flue gases
1. When the feeding door is opened, a s all a ount of gas can be released on the front boiler side. Never inhale this
gas.
2. When feeding solid fuels while the co bustion cha ber interior is glowing, protect your hands and face. Use
protective gloves.
Fuel co bustion
1. Do not re ove the fuel fro co bustion cha ber while still burning.
2. Do not atte pt to extinguish the burning fuel with water or other liquids.
3. Do not leave the feeding door or ashtray door opened while the fire is still present inside the co bustion cha ber.
4. Close the air inlets and chi ney outlets when trying to slow down the fire or stop it.
5. Your boiler can burn only solid fuels specified within the section “Technical para eters”.
Never use any different solid fuel which can be har ful to the structure of boiler sectional ele ents as well as any
liquid or gas fuel.
9. IMPORTANT WARNINGS
Adhere to safety instructions when installing and running the UNI boiler:
•The boiler can be operated only by adult persons familiar with these operating instructions. It is unpermissible to
leave children at the boiler beyond control of adults. Interventions into the boiler design that could threaten the
health of attending personnel or roommates are forbidden.
•The boiler is not intended for being operated by persons (including children) whose physical, sensual or mental
disability or lack of experience and knowledge inhibit them from a safe usage of the appliance unless being
supervised or instructed about the appliance usage by a person responsible for their safety.
•hildren should be watched in order to ensure that they do not play with the equipment.
•In case the flammable vapours or gas may be created and released into the boiler-room or when performing
activities during which a temporary risk of fire or explosion may occur (gluing of floor clothes, coating with
flammable paints), the boiler must be put out of operation before commencing such activities.
•It is FORBIDDEN to use flammable liquids for firing the boiler.
•It is FORBIDDEN to overheat the boiler during its operation.
•No subjects made out of flammable materials may be placed on the boiler or within a distance shorter than the
safety distance.
•When removing ash from the boiler, no flammable materials may be placed within the minimum distance of 1500
mm around the boiler.
•When operating the boiler at temperatures lower than 60° , a moisture condensation on the boiler drum may
occur (so called low-temperature corrosion) which shortens the boiler drum service life. Therefore, it is
recommended to operate the boiler at temperatures above 60° .
•After the heating season, it is necessary to clean up thoroughly the boiler, smoke stacks and smoke extension.
Lubricate the pivots, smoke flap mechanism and other movable boiler parts with graphite grease. Keep the
boiler-room clean and dry.
•Pertinent signs of corrosion on the boiler drum cannot be considered as defects and do not affect the boiler
function.
•The system must be fitted with a protection valve (maximum overpressure of 300 kPa) dimensioned in
accordance with the nominal boiler output. If you have any other questions, please address the respective
specialized installation companies and service organizations.
•In case the two-way safety device reacts adding the water that does not comply with ČSN 077401, it is necessary
to treat the water inside the system so that it meets again requirements of this standard.

•The UNI boiler must be connected to a suitable separate chimney designed in compliance with instructions stated
further within this manual and mandatory regulations. The chimney must show the draught values required for
the given boiler model. The boiler may not be operated unless the chimney connector is ready and sufficient
burning draught ensured.
•Always ensure a satisfactory fresh air supply into the boiler-room – see the instructions for placing and installing
the boiler.
•Do not install the boiler within an area being shared or used by persons or in the place with any direct openings
to habitable rooms.
•If the hydraulic circle is not equipped with the safety heat exchanger system according to instructions provided in
this manual, the boiler must be installed into the open system.
•Do not drain any water from the hydraulic circle except for the cases of maintenance or risk of frost. The
hydraulic system may be refilled with the anti-freeze fluid Friterm.
•Do not feed cold water directly into the boiler overheated for any reason. This might lead to cracking of boiler
sectional elements. When using the two-way safety valve DBV 1 – 02, the cooling water is gradually added into
return water.
•Do not fire the boiler with the front door opened.
•The heating system should enable the water flow corresponding to the boiler output and temperature difference
between the incoming and return water should not exceed 20° .
•heck regularly whether the heating system is filled with water.
•Boilers should be installed directly onto a flat and smooth floor made out of non-flammable materials. It is
recommended that the height of pedestal is 50 mm at least and its other dimensions are bigger than ground plan
dimensions of the boiler. This pedestal isolates the boiler from water spilled on the floor.
•If the boiler is installed into an old heating system, the heating system must be rinsed and cleaned from all
contaminants before the boiler is connected.
•Your boiler cannot switch the pump on and off automatically. The pump must be switched on if the boiler
temperature is higher than temperature of cold water or if the fuel is burnt inside the combustion chamber.
Never switch the pump off unless the fire is completely quenched.
•Water in the boiler should never reach high temperatures when the pump is switched off. In such a case, an
immediate supply of cold water into the hot boiler may cause cracks of the boiler drum due to high thermal
energy.
•If the draught controller does not work properly, change its adjustment step by step as described in the draught
controller manual.
•If the chimney draught is not sufficient or completely missing (e.g. the chimney is blocked, uninsulated or built
incorrectly, etc.), you can experience combustion difficulties (no fire, excessive smoking, condensation resulting
from the cold flue gases). In this case, it is strictly recommended to inspect the chimney by an expert and repair
all possible irregularities. Your boiler has been designed on the principle of natural draught – therefore, the
correct chimney installation is so important.
10. Guidelines on the product end-of-life disposal
It is recommended to dispose the wrappage as follows:
- Plastic foil, cardboard package – use the junk services.
- Metal strapping tape – use the junk services.
- Wooden base is disposable and cannot be further utilized as a product. Its liquidation is subject to the law No.
94/ 2004 oll. and 185/2001 oll., as subsequently amended.
Because the product is made out of ordinary metal materials, it is recommended to dispose single components as
follows:
- Exchanger (grey cast-iron) – use the junk services.
- onduits, shell – use the junk services.
- Other metal parts – use the junk services.
- Insulation material ISOVER – use a company dealing with waste collection and disposal.
11. Warranty and liability for defects
Manufacturer provides the following warranty:
– Boiler: 24 months since the date of putting the product into operation; 30 months at most since the date of
dispatching from the manufacturing plant.
– Boiler drum: 5 years since the date of dispatching from the manufacturing plant.
The user is obliged to entrust a specialized installation company with putting the boiler into operation whereas all
defects may be solved and removed only by a professional contractual service organization – if this is not
respected, no warranty on the proper boiler function is applicable. After filling in the form “Certificate of quality
and completeness of the UNI boiler”, it serves as the “Certificate of warranty”.
The user is obliged to perform a regular maintenance on the boiler.

Any notice of failures must always be made in writing and by phone without any delay after the respective defects
have been found.
If the given instructions are not observed, the warranty provided by the manufacturer cannot be recognized. The
manufacturer reserves the right to alterations resulting from the product innovations which may not be contained
within this manual.
The warranty does not apply to:
- Defects caused by incorrect installation procedures, incorrect product operation or incorrect maintenance – see
the chapter 9.
- Damage of the product during the transportation or other mechanical damage.
- Defects caused by incorrect storage conditions.
- Defects caused by neglecting the water quality within the heating system – see the chapter No. 5.1. and 6.2.
- Defects caused by neglecting the instructions stated in this manual.
The manufacturer reserves the right to alterations resulting from the product innovations which may not be
contained within this manual.

Figure No. 11 – Boiler asse bly

Legend to the figure No. 11
Position Title Position Title
1Front sectional ele ent 33 S oke flap controller
2Central sectional ele ent 34 S oke flap
2Central sectional ele ent with recess 35 Flange seal
3Rear sectional ele ent 36 Flange
4Nipple 37 Draught controller
5Anchor bolt 38 Right shell side part including insulation
6Boiler dru botto 39 Left shell side part including insulation
7Reduction 1 1/2"-1/2" 40 a 41 Upper shell part including insulation
8Ther o eter well R1/2" 42 Rear shell part including insulation
9Plug 1 1/2" 43 Ther o ano eter
11 Feeding door cover 44 Identification label
12 Feeding door insulation 46 Ashtray
13 Special pad under the door insulation 49 Feeding door closure plate
14 Gasket – dia eter 12 50 Suspension plate
15 Auxiliary air choker 51 Suspension plate hangers
16 Auxiliary air choker screw ANut M12 TS1026/1
17 Ashtray door cover BWasher A13 TS 79/2
18 Ashtray door insulation CScrew M6x40
19 Pri ary air choker DNut M6 TS1026/1
20 Pri ary air choker axis FWasher A8.4 TS79/2
22 Feeding door handle GNut M8 TS1026/1
23 Door handle fixing screw HScrew M8x15
24 Door handle IScrew M8x20
25 Co bustion cha ber door JScrew M6x30
26 Swivel KScrew M10x25
27 Co bustion cha ber door suspension MWasher A10.5 TS 79/2
28 Upper door suspension NRetaining stirrup ring
29 Botto door suspension RScrew M6x12
30 Door closure bushing SScrew M10x40
31 Door closure pin TNut M10 TS1026/1
32 S oke extension

OPOP s.r.o.,
Valašské Meziříčí
Boiler UNI – Certificate of warranty
Boiler serial nu ber …………………………………………………………………. Boiler output…………………………………………………………
User (surna e, first na e)………………………………………………………………………………………………………………………………………………………
Address (street, city, postcode)……………………………………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………………………………………………………………….
Telephone/fax ………………………………………………………………………………………………………………………………………………………………
Boiler eets the following require ents:
ČSN EN -5: Boilers for central heating syste s – Part 5: Central heating solid fuel boiler with anual or auto atic fuel supply and
axi u no inal output of 300 kW – ter inology, require ents, testing and arking.
Manufacturer provides the following warranty:
- Boiler: 24 onths since the date of putting the product into operation; 30 onths at ost since the date of dispatching
fro the anufacturing plant.
-Boiler dru : 5 years since the date of dispatching fro the anufacturing plant.
Conditions for the warranty validity:
-Boiler installation and putting into operation ust be perfor ed according to “Boiler installation and operating
instructions” by a specialized installation co pany.
-Re oval of defects ust be executed by a specialized service organization.
-Co pleteness of the boiler delivery is guaranteed by the anufacturer.
This certificate of warranty is not valid if sub itted blank.
User’s confir ations:
-The user confir s that the boiler has been adjusted by a specialized installation co pany and did not show any defect
during the heating test.
-The user confir s to have received “Boiler installation and operating instructions” together with properly executed
Certificate of warranty and Certificate of quality.
- The user confir s to have been acquainted with the boiler operation and aintenance.
…………………………………….. …………………………………….. ……………………………………..
Dispatch date Manufacturer’s sta p Checked by (signature)
…………………………………….. …………………………………….. ……………………………………..
Date of installation and putting
into operation
Installation co pany
(sta p, signature)
User’s signature