Opop H 425 EKO User manual

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OPOP, LLC
Zašovská 750, 757 01 Valašské Meziříčí
Tel.: [phone], fax: [phone]
WATER HEATER H 425 EKO
Content
1. Introduction 2
2. Characteristics of the water heater 2
3. Technical description 2
4. Technical parameters 6
5. List of replaceable parts 9
6. List of supplied accessories 10
7. Assembly of basic accessories 10
8. Water heater operation 12
8.1 Starting the fire 12
8.2 Stoking and opening the ash doors 12
8.3 Ash removal 13
8.4 Cleaning the water heater 13
9. Maintaining the water heater and the heating apparatus 14
10. Safety instructions for the assembly and operation of the water heater 15
10.1 Assembly and setup of the draft regulator 16
10.2 Assembly of the discharge valve 16
10.3 Connecting to the chimney 16
10.4 Sorting construction products and structures based on their reaction
to fire 17
10.5 Water heater location –important warnings 18
10.6 Instructions for assembling and using pressurized expansion containers 18
10.7 Connecting the water heater to a protection device against overheating 19
10.8 Safety instructions for the water heater operation 21
11. Waste removal 23
12. Determining the size of the accumulation reservoir 24
13. Malfunction measures 24
14. Safety and other regulations 25
15. Warranty card 26

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1. INTRODUCTION
Dear customer:
We appreciate very much that you have chosen a product from our production line and become
therefore one of our customers. We believe you will be fully satisfied with our product. We hope
that the product will prove to be reliable and will serve you for a long time. All employees of our
company have contributed to it and now you can participate in the process too - by careful reading
the manual and by complying with all prescribed rules and regulations.
OPOP, LLC
2 . CHARACTERISTICS OF THE WATER HEATER
The design and surface of the steel water heater of the H4xx EKO line are designated for individual
and central heating of family houses or suitable production facilities with a maximum hydrostatic
height of the heating water of 20 m. The H425 EKO water heater is designed for burning solid fuels,
i.e. brown coal and wood (burning other materials, for example, plastic, is not acceptable!). The
boiler has to be connected to a chimney that corresponds to the power output of the boiler. Besides a
professional installation and correct service, a good performance of the boiler requires a sufficient
draft. This boiler was certified by the Machinery Testing Institute in Brno in accordance with ČSN
EN 303-5.
3. TECHNICAL DESCRIPTION
The upper part of the boiler is formed by an insulation cover, which significantly contributes to the
overall thermal insulation and, at the same time, preheats air that enters the boiler via the valve in
the stoking door. Under this cover, there is the already mentioned stoking door, which is attached to
the weldment by a pin system. The cleaning door is attached to the weldment by butterfly nuts. All
types of doors are sealed to the boiler body by a thermal insulation cord. The actual boiler body is
welded from steel plates. The boiler is completely insulated (including the inside bottom part)
against thermal leaks to the surroundings, which significantly influences its efficiency.
When looking from the above, the boiler body is divided by water partitions into three parts:

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a) The front area behind the boiler head wall is formed by a feeding shaft with a cast-iron, sliding
grate.
b) The middle part forms the burning area, padded with a fireclay lining and a stainless steel pipe,
through which about 40% of secondary air flows. The remaining 60% of the air flows through two
side openings, located immediately under the first water plate.
c) The rear part of the boiler is formed by a reverse draft, where the combustion products flow under
the bottom part of the last partition and rise to the smoke hub. In the upper part of this area, there is
a sliding stoking valve, which allows for a direct draft of the combustion products into the smoke
hub when initially making fire.
The furnace chamber consists of a slanting and sliding cascade cast-iron grate. These grates are
controlled by the grate lever on the side of the boiler. The volume of incoming secondary air can be
mechanically adjusted (in the case of the H425 EKO water heater) by revolving valves located on
both sides of the boiler.
Setting up secondary air flow for brown coal (nut 1):
Under normal operation with nominal power output and when using brown coal (fossil fuel), the
valves are open as it is showed on Picture A. It means that the handles of both revolving valves (left
and right side) are in the position that they point exactly towards the marked line.
Picture A
Setting up secondary air flow for wood (maximum length of 39 cm):
Under normal operation with nominal power output and when using wood (biological fuel), the
valves are open as it is showed on Picture B. It means that the handles of both revolving valves (left
and right side) are in the maximum opening position.

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Picture B
Note
- A great advantage of the perfect burning of this boiler is the fact that the secondary air, which we
can regulate by the above mentioned revolving valves, is preheated! Preheating takes place in the air
chamber, which forms a part of the boiler body. It means that the air that enters the fire chamber and
the area between the partitions does not have the temperature of the surrounding environment
(usually 10-20°C) but rather a temperature that oscillates around 80-90°C. This system significantly
contributes to the prevention of tarring and prolongs the lifespan of the boiler body.
- The fireclay lining is important for a perfect combustion of burnt gases (works as a “catalytic
convertor”). Because of that, this boiler produces very low emissions. Furthermore, the lining
accumulates heat and is therefore able to transmit heat to the heating system even after all the fuels
are burnt.
On the bottom part of the front wall, there is an ash door, which secures the needed intake of
primary air to the combustion chamber. The ash door is equipped with a manually controlled
opening for regulating the volume of incoming primary air. Under normal operation with nominal
power output and when using brown coal and wood, the revolving opening is always in the same

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position. This position is marked by a line for an easy orientation –see Picture C. The power output
of the boiler can be increased by making the opening gradually bigger.
Picture C
The mouthpiece for adding water as well as the smoke hub are located on the center axis of the rear
part of the boiler. The mouthpiece for water output is moved sideways from the center axis by 140
mm. The upper part includes a G3/4" mouthpiece for attaching the regulator of combustion air and a
G1/2" mouthpiece for attaching a sensor of the overheating fuse device. The bottom part has a
G1/2" mouthpiece for the discharging and feeding valve.
Boiler walls are thermally insulated by a 40-mm layer of mineral wool and covered with treated
cover plates. The stoking, cleaning and ash doors are made of sheet-metal, surface-treated parts and
they are thermally insulated as well. The front cover plate is furnished by the following informative
measurement devices for monitoring temperature and pressure of the heating water inside of the
boiler:
Capillary thermometer TCS 48 (technical data –scale range: 0 to 120 °C; measuring range: 20 to
100 °C; accuracy: ±4% of the scale range)
Manometer MCS 48 (technical data - scale range: 0-4 bars; scale divisions: 0.1 bars; accuracy:
±2.5% of the scale range)
4 . TECHNICAL PARAMETERS
Table 1
WATER HEATER H425 EKO

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Table 2
Note
- Fuel
consump
tion is
directly
dependen
t on the
quality
and type
of the
used fuel
and also
on
keeping
the
internal
heat-
radiating
areas of
the boiler
clean.
The
smaller
are the used split wooden pieces, the greater output can be achieved, however, the burning time
shortens. To the contrary, when we need a lower output, we can use bigger pieces of wood, which
will prolong the burning time.
*
1
The actual size of the accumulation reservoir must be determined by a project engineer.
Parameter name
Unit
Coal
Wood
Operational draft - prescribed
Pa
22
Operational draft - minimal
Pa
15
Nominal heat output
[kW]
25
22
Efficiency
[%]
79.4
79.3
Boiler class pursuant to ČSN EN 303-5
3
3
Guaranteed fuels
-
Brown coal
nut 1
Split
hardwood,
length up to
39 cm,
humidity up to
20%
Water volume
[ l ]
41
Flue diameter
[mm]
150
Fuel consumption
[kg/hour]
4.2
6.0
Temperature range of heating water
[°C]
65 - 90
65 - 90
Volume of the fuel shaft
[ l ]
55
Dimensions of the stoking opening
[mm]
176 x 405
Heating area
[m2]
2.3
Temperature of burnt gases under nominal
heat output
[°C]
303
265
Maximal excess pressure of heating water
[MPa]
0.2
Testing excess pressure of heating water
[MPa]
0.4
Weight flow of burnt gases under nominal
output
[kg/s]
0.016
0.015
Combustion time under nominal output
[h]
>4
>2
Hydraulic loss under DT= 20/10 K
[mbar]
1.1 –4.8
Volume of the accumulation reservoir*1
[l]
1,050
462
WATER HEATER H425 EKO
Boiler weight
[kg]
245
Mouthpiece type output / input (internal thread)
Js
G1 1/2"
Cooling loop connector (internal thread)
Js
G 1/2"
Discharge and filling connector (internal thread)
Js
G 1/2"
Connector for installing the output regulator
(internal thread)
Js
G 3/4"
A –total height of the boiler
[mm]
969
B –total depth of the boiler
[mm]
820
C –boiler width
[mm]
635
D –flue location
[mm]
705
E –location of the intake water mouthpiece
[mm]
107.5
F –location of the output water mouthpiece
[mm]
792.5
G –location of the output water mouthpiece in
relation to the center axis
[mm]
140
H –depth of the boiler base
[mm]
577
Thickness of the walls of the boiler body
(water/flame)
[mm]
5
Thickness of the walls of the boiler body (water)
[mm]
3

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Množství
1
1
1
3
3
1
1
1
1
2
1
1
1
Název dílu
Roštovací mechanismus
Posuvný rošt litinový
Šikmý rošt litinový
Šamotová tvarovka_II (30x275x400)
Šamotová tvarovka_I (30x100x400)
Šamotová tvarovka III (30x200x400)
Plech zatápěcí klapky
Táhlo zatápěcí klapky
Páka roštovacího mechanismu
Pant horního víka
Popelníková zásuvka
Regulátor tahu
Teploměr TCS 48
Poz.
19
22
23
24
25
26
28
29
31
33
34
42
43
Množství
1
1
1
1
1
1
1
1
1
1
1
1
1
Název dílu
Těleso kotle H425 EKO
Trubka sekundáru
Čistící uzávěra
MANOMETR MCS 48
Kryt boční (levý)
Kryt přední
Zadní kryt
Kryt boční (pravý)
Popelníková dvířka
Růžicová rukojeť
Přikládací dvířka
Čistící dvířka
Horní kryt
Poz.
4
2
3
4
6
7
8
9
11
14
15
17
18
TEPLOMĚR
CHLADÍCÍ
SMYČKA
MANOMETR
REGULÁTOR
TAHU

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Daiagram: DRAFT REGULATOR, MANOMETER, COOLING LOOP,
THERMOMETER
Table:
Position
Part name
Quantity
Position
Part name
Quantity
4
H425 EOK boiler
body
1
19
Grate mechanism
1
2
Secondary pipe
1
22
Sliding cast-iron
grate
1
3
Cleaning lid
1
23
Slanting cast-iron
grate
1
4
Manometer MCS
48
1
24
Fireclay fitting II
(30x275x400)
3
6
Side cover (left)
1
25
Fireclay fitting I
(30x100x400)
3
7
Front cover
1
26
Fireclay fitting III
(30x200x400)
1
8
Rear cover
1
28
Plate of the fire-
starting valve
1
9
Side cover (right)
1
29
Pin of the fire-
starting valve
1
11
Ash door
1
31
Grate mechanism
lever
1
14
Rose handle
1
33
Upper lid hinge
2
15
Stoking door
1
34
Ash drawer
1
17
Cleaning door
1
42
Draft regulator
1
18
Upper cover
1
43
Thermometer TCS
48
1

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5. List of replaceable spare parts
List of spare parts Position of the spare part from page 8
1) Stoking door 15
2) Cleaning door 17
3) Ash door 11
4) Slanting cast-iron grate 23
5) Sliding cast-iron grate 22
6) Stoking valve plate / stoking valve pin 28, 29
7) Cleaning lid 3
8) Grate mechanisms 19
9) Ash drawer 34
10) Front cover 7
11) Side cover (left, right) 6, 9
12) Scraper and hook for cleaning boiler surfaces
13) Broom (holder + steel brush)
14) Manometer MSC 48 4
15) Draft regulator for combustion air 42
16) Filling / discharging valve
17) Stoking door handle
18) Secondary pipe 2
19) Rear cover 8
20) Rose handle 14
21) Upper cover 18
22) Lever of the grate mechanism 31
23) Upper lid hinge 33
24) Fireclay fitting I (30x100x400mm) 25
25) Fireclay fitting II (30x275x400mm) 24
26) Fireclay fitting III (30x200x400mm) 26
27) Thermometer TSC 48 43
Note
- Soft wood can be used in the boiler as well (for example, spruce, pine, alder, etc.). However, if you
use soft wood, the power output will be lower than stated by the manufacturer for hardwood.

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6. List of supplied accessories
1) Scraper and hook for cleaning boiler surfaces
2) Broom (holder + steel brush)
3) Filling valve
4) Draft regulator for combustion air
5) Manometer MCS 48, Thermometer TSC 48
6) Security thermal valve TS 130 or STS 20 (not a part of the package)
7) Lever of the grate mechanism
8) Operating manual with a warranty sheet
9) Cleaning lid
10) Secondary pipe
11) Plate of the fire-starting valve
12) Pin of the fire-starting valve with a ball
13) Fireclay lining:
- Fireclay fitting I (30x100x400mm)… 3 pieces (position 2, 6 and7 on Picture E)
- Fireclay fitting II (30x275x400mm)… 3 pieces (position 1, 5 and 8 on Picture E )
- Fireclay fitting III (30x200x400mm)… 1 piece (position 4 on Picture E )
14) Oven mitt for opening the stoking door
7. Assembly of basic accessories
a) Installing the stoking valve:
The stoking valve consists of three parts, plate of the stoking valve, pin of the stoking valve and a
ball. Assemble these parts in accordance with Picture D:
Picture D

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b) Installing fireclay lining and the secondary pipe:
Because the fireclay lining could get damaged during transportation, these fitting are delivered in a
separate package. After the boiler is placed in its location and connected to the given system, insert
the fireclay fittings in it in accordance with Picture E. Do so in the marked numerical order, i.e. 1, 2,
3 and so on. Insert the secondary pipe as third WITH THE HOLES FACING UP. When you insert
the last fitting, i.e. fitting number 8, push it against fitting number 7 in a way as to make sure they
are touching each other with their edges. Be careful not to damage the fireclay fittings during
installation.
Insert the fittings one by one in the appropriate numerical order, i.e. 1, 2, 3 and so on:
Picture E
1
2
3
4
5
6
7
8

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8. Water heater operation
Prior to starting the fire for the first time, the following has to be done:
1) Making sure that the boiler and the entire heating system is filled with water or some other
heat-conducting medium and correctly deaerated.
2) Making sure that the drafting routes are sealed.
3) Making sure that the cleaning lid (No. 3) is correctly installed in order to prevent suction
of false air into the area of the exchanger.
4) If you are using brown coal as the fuel, set the secondary valves (Picture A) to the
appropriate position. The same applies for wood - see (Picture B).
5) Using a small chain, the draft regulator shall be connected to the valve on the stoking
door. Prior to setting a fixed temperature, the valve can be half open.
8.1 Starting the fire
Making fire in the boiler is done in the same way like in a regular stove. Put paper on the grate
through the upper door and add starting spills and several bigger wood pieces. Light the inserted
load from the bottom (through the ash door) using a lit paper or fire starter (PEPO). Make sure the
primary air valve on the ash door is set correctly (in accordance with the recommended setup
showed on Picture B) and close it. Open the fire-starting valve (No. 28) by pushing the pin into the
boiler. If the draft in the chimney is too low, close the secondary air intake openings on the sides of
the boiler. When enough of the wood burns, gradually add more fuel but do not overload it, it could
suffocate the fire. Continue in this process until the level of added fuel exceeds the bottom edge of
the first partition. When that happens, you can add as much fuel as to fill the filling shaft up to such
a height that will allow for correct closing of the stoking door. When the fuel catches on fire, close
the stoking valve by pulling the pin on the rear wall of the boiler and open the secondary air intake
openings on the sides of the boiler in accordance with the recommended setup.
8.2. Stoking and opening the ash doors
To prevent escaping smoke when opening the stoking door and adding fuel or inspecting fire, follow
the following procedure:
Prior to stoking, close the air intake using the lid on the ash door and open the stoking door up to the
height of 1 to 1.5 cm in the front part of the stoking door. Wait about 10 seconds until the burnt
gases are exhausted and then close it completely. Add fuel and open the combustion air intake again.
If the chimney draft is good or the filling shaft is full, you do not need to follow the above stated
procedure.

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Note:
Upon reaching the required temperature of the output water (for example, 80oC), release the chain
on the holder of the regulator and set such a length that the valve is open only 2-3 mm. In this way,
the regulator will maintain the required temperature of the boiler. We do not recommend setting the
valve in a way that the suffocating lid on the stoking door is completely closed. The burning process
would significantly worsen.
8.3 Ash removal
In order to secure good access of the combustion air for perfect burning, we need to remove the
remaining parts of the fuel –ash from the grate. We can do so by rocking the lever that is installed
on the side wall of the boiler. The rocking motion moves the grate and the ash falls through to the
ash pit. If rough pieces of slag are created on the grate, we can remove it by rocking the lever even
more while the boiler is in operation. This motion slides the cascade grate out and the rough remains
of the fuel fell through to the ash pit. If the slag gets caught in the grate, shake it off by fast sliding
of the lever.
Follow the same procedure for cleaning the boiler after heating is terminated. Make sure that ash is
not collected in the area for the ash drawer; these remains could fell off outside of the ash drawer
and prevent correct sliding of the drawer in. When the boiler is operating, use the lever with caution!
It means that you should rock it only slightly, which should be enough for removing the burned fuel.
Otherwise you are risking that all fuel could fall through to the ash pit.
8.4 Cleaning the water heater
In order to achieve the maximum possible economy and therefore efficiency of the boiler, you
should properly clean the internal parts of the boiler body once every 3-5 days (depending on the
intensity and quality of the used fuel. We can do that by vigorous scraping of the deposit from the
walls using a scraper and steel brush, which form a part of the boiler accessories. WARNING!
Conduct the cleaning only when the fire in the boiler is out.
Follow the following procedure for cleaning:
a) Make sure that the ash drawer is in the ash pit area.
b) Disassemble the cleaning door (17). Remove the big fireclay fitting (note 8, page 11) with
the stoking valve (28). Using the hook, remove the cleaning lid (3), see diagram on page

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8. The cleaning lid closes the area between the rear air hole of the partition and the ash
drawer. Next, take out the fireclay lining with the secondary pipe from the boiler. Clean
the pipe thoroughly. Using the scraper and the steel brush, scrape off ash and soot from
the boiler walls. When you are done with the cleaning, put the cleaning lid (3) back and,
using a portable lamp placed in the ash pit area, make sure that the cleaning lid is correctly
set in.
c) Using the same procedure in reverse, put back in the fireclay lining, secondary pipe,
fireclay fitting (note 7, page 11), stoking valve (28) and fireclay lining (note 8, page 11).
Close the cleaning door and tighten the butterfly nuts of the cleaning door.
d) Clean the filling shaft in the front part of the boiler through the open stoking door.
e) Close the stoking door and, using short, rocking moves, remove remaining slag and ash
from the grate.
f) Remove the ash drawer through the ash door, remove the content of the ash drawer, clean
the area of the ash drawer from slag and ash, which fell outside of the ash drawer during
cleaning or moving the grate, and close the ash door.
WARNING!!!
9. Maintaining the water heater and the heating apparatus
Prior to putting the heating apparatus into operation, fill the water system of the heating apparatus
with water (soft water if possible). From time to time, inspect the water condition in the heating
apparatus. Never overheat the boiler, i.e. do not exceed 90°C. Gentle bubbling in the boiler’s body
with water temperature over 80°C does not represent any problem. If the boiler is slightly pulsing or
vibrating, it is not a defect either. The reason of these movements is the fact that the boiler is
burning fuel so well that it burns all oxygen, which it has available at the given moment, and it is
lacking it. As a result of this process, explosive gases are collected under the first water plate. These
gases begin to burn and that results in slight pulsing vibration. Moreover, it is important to make
sure that the boiler is always deaerated and the overall system filled with water. If necessary,
antifreeze liquid Friterm (www.velvana.cz) or anticorrosion inhibitor Inhikor II can be added to
water in the water system.
Removed ash has to be put into non-flammable containers with a
lid. Also, protective aids should be used and principles of personal
safety observed.

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Note:
Water hardness must comply with ČSN 07 7401. If it does not, it is necessary to treat the water
appropriately in order to achieve the values from the following table:
The user
is obliged
to use
professio
nal
service
for putting the boiler into operation, regular maintenance and repairs.
10. Safety instructions for the assembly and operation of the water
heater
The boiler for solid fuels can be installed only by a company with a valid authorization to do so or
persons authorized by our company (see the list of the service companies; the list is available from
the company service technician). A project has to be prepared for the installation in accordance with
the valid regulations. Here, we are stating a summary of the basic assembly conditions.
Prior to putting the boiler into operation, it has to be fully assembled (elements, which have to be
installed after transporting the boiler, are stored in the ash pit as accessories of the boiler).
We recommend a professional inspection of the boiler to be conducted once a year, ideally before
the heating season. The inspection should focus on correct installation of the exhaust, expansion
reservoir, wear and tear of the grates, etc. The inspection should also inspect correct function of the
cooling loop and draft regulator.
10.1 Assembly and setup of the draft regulator
In the rear part of the boiler, a ¾” mouthpiece is welded for installing the boiler’s draft regulator.
Screw the shaft of the draft regulator into this mouthpiece (water resistant connection –pack it with
the sealing cord). When the boiler is lit, set the draft regulator to at least 70 oC. When the
temperature on the thermometer reaches 70 oC, check the position of the suffocating lid. It shall be
slightly open –between 2-3 mm. This suffocating lid should never be completely closed.
If the opening of the suffocating lid does not correspond to the setup, extend or shorten the chain of
the draft regulator.
Recommended values
Hardness
mmol/l
1
Ca2+
mmol/l
0.3
Concentration of the total Fe + Mn
mg/l
(0.3)*
*) recommended value
The manufacturer recommends installing a suitable mixing device
in the heating circle, especially when using a circulation pump, in
order to make sure that the input temperature of the heated water in
the boiler does not drop under 65°C.

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Note:
10.2 Assembly of the discharge valve
At the rear bottom part of the boiler, a ½” mouthpiece is welded. Screw (and pack) the discharge
valve into it. After you fill the system with water, this valve must be closed!
10.3 Connecting to the chimney
Recommended diameters of chimneys for central heating boilers –these data are only informational.
Boiler output
kW Chimney height 8m Chimney height 12m Chimney height 15m
12 15 x 15
18 15 x 20
25
Ø180 mm
30 Ø 180 mm
35
Ø200 mm
49.5
Ø200 mm
Chimney diameter mm
The boiler can be connected to a chimney only in accordance with ČSN 73 4201:2002 (Designing
chimneys and flues).
Water heaters can be connected to a chimney only with consent by the appropriate chimney
sweeper organization.
The boiler has to be connected to a separate chimney flue with a sufficient draft for all practically
possible operational conditions. Warning! Chimney draft is always smaller during higher
humidity, fog and when the chimney head is hot as a result of a long exposure to the sun.
The pipe outlet attached in the flue and installed to the smoke hub of the fuel appliance must be
correctly assembled and installed in order to avoid random or spontaneous loosening. We
recommend that the flue between the boiler and the chimney is not longer than 1 meter and that it
The longer the burning period after grating, the smaller volume of
secondary air is necessary, and vice versa.

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should rise toward the chimney; the recommended slant is at least 5% (3°). We also recommend that
it is attached directly - no more than one pipe elbow.
The water-heating system must be executed in accordance with ČSN 06 0310:2006 (Central
Heating, Project Design and Assembly), ČSN 06 0830:2006 (Security Devices for Central Heating
and Service Water Heating), ČSN 07 7401 (Water and Steam for Thermal Energy Devices with
Steam Working Pressure up to 8 MPa, ČSN EN 303-5 (Boilers for Central Heating –Part 5: Boiler
for Central Heating with Solid Fuels with Manual or Automatic Delivery and with Nominal Output
up to 300 kW).
The boiler and the flue must comply with the following fire standards: ČSN 06 1008:1997 (Fire
Safety of Thermal Devices), ČSN EN 13501-1:2007 (Fire Classification of Construction Products
and Construction Structures - Part 1: Classification Based on the Fire Test Results). They can be
installed in a safe distance of 400 mm from flammable substances. This safety distance has to be
complied with even if the flammable class of the given flammable substance is not known.
The safety distance can be reduced by 50% if you use a non-flammable, thermally insulating,
screening board of class A, at least 5 mm thick and placed 25 cm from the flammable substance (air
insulation).
10.4 Sorting construction products and structures based on their reaction
to fire (pursuant to ČSN 73 4201, Article 4.5)
a) Non-flammable materials –they are safe from the fire perspective, i.e. they comply with the fire
reaction class of A1 or A2 in accordance with ČSN EN 13 501-1.
b) Flammable materials –fire reaction class of B, C, D, E and F in accordance with ČN EN 13 501-
1.
10.5 Water heater location –important warnings
The boiler must be installed in accordance with ČSN 33 2000-3:1995 in basic environment
AA5/AB5.
Placing the boiler in living quarters is not allowed. In the room where the boiler is installed, intake
of combustion air must be secured permanently.
The boiler must be installed in compliance with the requirements of ČSN 06 1008 – Fire Safety of
Thermal Devices. Items made of flammable materials must not be placed on the boiler or closer to
the boiler than the specified safe distance. The safe distance must be complied with even in the case
of accessory subjects, fire starting material and fuel in the boiler room.

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The boiler must be installed on a non-flammable, thermally insulating mat that overlaps the boiler
on the side of the ash doors by at least 300 mm and by at least 100 mm on the other sides.
If there is a possibility of a temporary occurrence of flammable gases or vapors, or during works
when a temporary fire hazard or explosion hazard could arise (for example, when pasting linoleum,
PVC, etc.), the appliance must be shut down prior to the occurrence of such a fire hazard.
Boiler and fuel location in relation to the necessary handling area:
-A handling area in front of the boiler must be at least 1,000 mm;
-Minimal distance between the rear part of the boiler and the wall shall be 400 mm;
-An access of at least 400 mm to the rear part of the boiler shall be preserved at least on
one side of the boiler;
-It is not allowed to store fuel behind the boiler or closer than 400 mm from the boiler;
-To store fuel in between two boilers in the boiler room is also not allowed;
-The manufacturer recommends to keep a distance between the boiler and fuel of at least
1,000 mm or to put fuel in a separate room.
10.6 INSTRUCTIONS FOR ASSEMBLING AND USING PRESSURIZED EXPANSION
CONTAINERS
1) The intake pipe leading to the expansion container shall be as short as possible without closures
and with dilatation option. The expansion container must be placed in a location that prevents
heating the container by radiating heat.
2) All heating systems must be designed in accordance with ČSN 06 0830 (Safety Devices for
Central Heating and Service Water Heating) and equipped with at least one dependable safety valve,
located on the output pipeline or the boiler, and a manometer. Location, assembly and diameter of
the safety valves must comply with ČSN 06 0830.
3) When installing the safety valve, you have to inspect accuracy of its setup by applying excess
pressure of 180 kPa, under which the safety valve has to open. If the setup of the safety valve is not
done correctly, you have to do it again and verify it as well.
4) Assembly and setup of the safety valve, its testing and adjusting the gas pressure in the
pressurized expansion container can be executed only by an authorized company. Prior to filling the
system with water, you need to determine the pressure in the pressurized expansion container,
provided it is higher than the hydrostatic height in the system.
5) The heat source has to be equipped, among others, in accordance with ČSN 06 0830 and ČSN EN
303-5; boilers for burning solid fuel shall be equipped with a draft regulator. The highest permitted
working temperature is 90°C.
6) The pressurized expansion container and intake pipeline shall be protected against water freezing.
7) Adjust the value of the filling gas excess pressure in the expansion container by releasing the
pressure to the value of the hydrostatic pressure of the cold system. The adjustment shall be
executed using the auto-valve on the pressurized expansion container. The excess pressure is

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measured using a manometer for measuring tire pressure. By adding water, adjust the pressure to a
value that is higher by 10 kPa, at the most, than the hydrostatic height in the system.
8) Once you fill the system with water, mark the adjusted hydrostatic height and maximum pressure
in the system upon reaching water temperature of 90°C by drawing the appropriate lines on the
manometer.
9) Shall the pressure difference marked by the lines on the manometer change during operation, i.e.
the minimal or maximum pressure is exceeded, you need to inspect the system, deaerate it, add
water to it in cold conditions or, if necessary, increase the gas pressure in the pressurized expansion
container in accordance with the instructions of the manufacturer.
10)Each pressurized expansion container must be inspected at least once a year. Such an inspection
shall include an inspection of the filling pressure.
11) An approved project shall be prepared and approved for each heating system and a device for
exhausting excessive heat connected to it. Assembling and connecting the boiler shall be conducted
in accordance with the above stated conditions.
12) If a correct pressurized expansion container is selected, the real pressure difference must not
exceed 60 kPa for water temperature in the system between 10°and 90°C. This pressure difference
can be tested during a heating test, when the water in the system is gradually heated from its cold
condition. If the real pressure difference exceeds 60 kPa, the pressurized expansion container is
incorrectly designed and a damage hazard of the boiler arises.
10.7 CONNECTING THE WATER HEATER TO A PROTECTION DEVICE AGAINST
OVERHEATING
In accordance with ČSN EN 303-5 and Government Directive 26/2003 Coll., the H425 EKO boiler
is equipped with a safety heat exchanger for exhausting excessive heat. This device secures the
highest permitted water temperature in the boiler, i.e. 110°C, is not exceeded. This safety heat
exchanger is designed as a flow water heater, controlled at its input by a safety discharge valve.
The connecting dimensions of the given mouthpieces allow for usage of two types of valves, either
the TS 130 safety discharge valve with a doubled sensor from Honeywell or the STS 20 boiler
overheating fuse from Watts. Our product is certified for both of these valves. The connection
diagram is the same for both valves.
Warning:
Execute the assembly and connection in accordance
with the stated diagram on page 20, Picture F, and with
the manufacturer’s instructions. We do not recommend
a different connection of a cooling loop.

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Cooling loop connection:
Picture F
Combustion air
draft regulator
Discharge of the
cooling water
Mouthpiece for
attaching a safety
valve against
overheating
Safety valve
sensor
Cooling loop