THERMOSTAHL ENERDENSE Manual

GAS/LIQUID FUELED STEEL BOILER
ENERDENSE
INSTALLATION AND SERVICE MANUAL
VERSION:
2.1
UPDATE:
12.04.2022

Contents
1. GENERAL INFORMATION ................................................................................... 3
1.1. Proper use of the appliance ................................................................................ 3
1.2. Safety warnings ................................................................................................ 3
1.3. Data label ........................................................................................................ 3
1.4. Document information ....................................................................................... 3
2. TECHNICAL FEATURES AND DIMENSIONS ......................................................... 4
2.1. Technical features ............................................................................................. 4
2.2. Function principle .............................................................................................. 4
2.3. Working medium............................................................................................... 5
2.4. Dimensions ...................................................................................................... 6
2.5. Fuel................................................................................................................. 7
3. BOILER MOUNTING ........................................................................................... 7
3.1. Transportation and delivery ................................................................................ 7
3.2. Boiler room ...................................................................................................... 8
3.3. Chimney ........................................................................................................ 10
3.4. Condensate drainage ....................................................................................... 10
3.5. Mounting the burner ........................................................................................ 11
3.6. Mounting the control panel ............................................................................... 12
3.7. Door adjustment ............................................................................................. 13
4. INSTALLATION ................................................................................................ 14
4.1. Hydraulic connections ...................................................................................... 14
4.2. Expansion vessel ............................................................................................. 14
4.3. Safety features ............................................................................................... 15
4.4. Filling the system ............................................................................................ 15
4.5. Connection diagrams ....................................................................................... 16
5. ELECTRICAL CONNECTIONS ............................................................................ 17
5.1. General instructions......................................................................................... 17
5.2. Control panel functions .................................................................................... 17
6. BOILER START-UP ........................................................................................... 19
6.1. Initial lighting checks ....................................................................................... 19
6.2. Start-up ......................................................................................................... 19
6.3. Checks to carry after initial start-up .................................................................. 19
6.4. Combustion regulation ..................................................................................... 20
7. SERVICE AND MAINTENANCE .......................................................................... 21
7.1. Cleaning the boiler .......................................................................................... 21
7.2. Maintenance after long stop.............................................................................. 21
7.3. Basic service procedures .................................................................................. 22
8. TROUBLESHOOTING ........................................................................................ 22

GENERAL INFORMATION
3
1. GENERAL INFORMATION
1.1. Proper use of the appliance
Before you make use of this appliance make sure you have read and fully understood the
instructions included in this manual.
The installation and use of the appliance must be performed according to the instructions
indicated in this manual in combination with the current national safety regulations.
The appliance is designed for use in pumped hot water central heating systems. Any other use
is considered improper and is prohibited. THERMOSTAHL declines any responsibility for
damages or injuries caused by improper use; in this case the risk is completely at the user’s
responsibility.
To ensure an efficient and flawless function of the appliance, it is strongly recommended that
you have performed an annual service by a qualified technician.
1.2. Safety warnings
All installation and maintenance procedures must be carried out by professional and authorized
personnel, in compliance with the indications in the present manual and national regulations.
Any failure to correctly install this appliance could cause damage or injuries!
Do not make modifications to parts of the appliance, unless you have contacted the company
and an authorized service contractor.
Only original accessories and spare parts must be used to ensure correct and safe function.
Make sure you respect the cleaning and maintenance procedures on the corresponding
intervals. Failure to do so can cause malfunction to the appliance and possible damages.
The boiler is design to function on the fuels indicated in the corresponding paragraph. Any
other fuel is prohibited. Do not use explosive or flammable substances! Do not store such
substances inside the boiler room.
The working pressure varies according to the model. Make sure you use the appropriate water
pressure. Working in a pressure higher than the one indicated in this manual is
strictly prohibited and dangerous!
1.3. Data label
The data label of the appliance is placed on the boiler’s side cover, on the external part. Make
sure that it is properly placed and readable.
On the label it is indicated the serial number and the manufacturing year of the appliance.
1.4. Document information
This document is an integral and indispensable part of the product and must be retained in
good condition by the user. Keep it in a safe place for future reference.
If the appliance is sold or transferred to another person, this manual has to always follow the
appliance and handed to the new user or installer.

TECHNICAL FEATURES AND DIMENSIONS
4
2. TECHNICAL FEATURES AND DIMENSIONS
2.1. Technical features
The ENERDENSE boiler is a high efficiency steel boiler, with horizontal condensing heat
exchanger, function for liquid or gaseous fuel.
The heat exchanger is made of special stainless steel, corrosive resistant, which ensures
optimal heat transfer from flue gas to the water.
It functions on the principle of reversed flame, and then guidance of the flue gases towards the
third pass, positioned at the upper part of the boiler, where they are further cooled until the
condensing temperature. The heat absorbed by the condensation preheats the water entering
the boiler. Flue gas temperature at the exit of the boiler is 55oC.
It is appropriate for function with pressurized burner for light oil or natural gas.
DESCIPTION OF COMPONENTS
▪Steel boiler body with INOX heat exchanger
▪High efficiency INOX turbinators
▪Removable rear smoke box with condesnsate evacuation tube
▪Front door insulated with refractory material, equipped with a flange for burner mounting
and a flame inspection pipe
▪Rockwool body insulation of 50 mm thickness
▪Electrostatically painted external covers
▪Control panel for electromechanical operation (optional)
2.2. Function principle
ENERDENSE is a high efficiency steel boiler with condensing heat exchanger, for function with
liquid or gaseous fuel.
The heat exchanger is made of special inox steel, with high corrosion resistance, which ensures
optimal heat transfer from the exhaust gas to the water.
The function is based on reversed flame in the fire chamber, the exhaust gases are then
guided to the tubes of the third pass positioned at the lower part of the boiler, where they are
further cooled down until they reach condensing temperature. The heat obtained by the
condensing heat exchanger is used to pre-heat the water entering the boiler. The final
temperature of the exhaust gas is 55℃.
The unit is designed to function with liquid or gaseous fuel burner.
In a conventional boiler, the water is heated through the heat of combustion, and the resulting
flue gases are guided to the chimney. As a result, the energy contained in the flue gas is lost.
Condensing technology exploits these gases, which consist to a large extent of hot water
vapour. It extracts the flue gas heat and feeds the energy obtained into the heating circuit.
In order to extract this energy, water vapour must condense. It does this at a temperature of
below 55°C. The condensing boiler cools the steam through a specially designed heat
exchanger. The energy gained is used to preheat the cold heating water. The hot water then
passes into the primary heat exchanger where it is heated further to reach the desired
temperature. During this process, small amounts of waste water occur which must be disposed
of at the drainage.
Condensing boilers must be connected to a plastic pipe for the flue gas.

TECHNICAL FEATURES AND DIMENSIONS
5
2.3. Working medium
The ENDS boiler is designed for function with water as working medium, with a maximum
concentration in polypropylene glycose of 50%.
The maximal temperature of the water is 95ºC. For condensing regim the return
temperature must be maximum 35oC. The boiler is appropriate for open and closed heating
systems with maximal operation pressure 6 bars.
The quality of the heating plant water is an important element for the performance of the
system. The water that enters the heating plant must be clean, transparent and free from salts
and chemical substances. It must be filtered, so as no quantity of sand or mud from the water
supply comes into the boiler.
The hardness of the water must be within permissible limits. In regions where the water is
hard, it is necessary to use water softeners.
Properties of the water for use:
▪Total hardness lower than 0.9 PH, 0.5 DH
▪P2O5–content 2-3 mg/lt
▪Alkalinity 200-800 ( mg NaOH/lt )
▪PH of circulation water 9-9.5
▪Hydrazine content ( Ν2Η4) 2 mgr/lt

TECHNICAL FEATURES AND DIMENSIONS
6
2.4. Dimensions
TECHNICAL DATA
Boiler type
ENDS
125
ENDS
200
ENDS
300
ENDS
400
ENDS
500
ENDS
600
Nominal heat output 50/30oC
kW
125
200
300
400
500
600
Nominal heat output 80/60oC
kW
113
181
271
362
452
543
Back-pressure
mbar
1-2
1-2
2-3
3-4
3-4
3-4
Pressure drop
mbar
15
26
32
33
35
38
Water contents
lit
200
300
390
480
760
860
Weight
kg
405
540
740
830
1070
1150
Pmax
bar
6
6
6
6
6
6
Heat efficiency 50/30oC
%
105
105
105
105
105
105
Heat efficiency 80/60oC
%
95
95
95
95
95
Maximum condensation production (gas)
lit/h
17,4
27,8
41,8
55,6
69,5
83,5
BOILER
TYPE
H
B
E
D
W
F
L
L1
T1-T2
T3
T4
T5
T6
mm
mm
mm
mm
mm
mm
mm
mm
mm
mm
inch
mm
mm
ENDS 125
1140
124
780
150
660
380
1100
1605
DN50
202
1”
1½”
40
ENDS 200
1280
124
895
185
740
400
1350
1840
DN65
202
1”
DN50
40
ENDS 300
1340
124
925
185
840
400
1500
2060
DN80
252
1”
DN50
40
ENDS 400
1340
124
925
185
840
400
1800
2360
DN80
252
1”
DN50
40
ENDS 500
1530
124
1010
220
1040
450
1800
2400
DN100
302
1”
DN50
40
ENDS 600
1530
124
1010
220
1040
450
2000
2600
DN100
302
1”
DN50
40

BOILER MOUNTING
7
2.5. Fuel
The ENDS is designed for function with the following fuels:
1. Natural Gas, according to DIN 4756 and 4788, with lower calorific power 10,0 kWh/Nm3.
The delivery conditions of natural gas to the burner are stabilized by the Norm for natural
gas I 6-98, for gas with low pressure (p=50mbar)
2. Light oil fuel EL, according to DIN 4755 and 4787, with a viscosity of 4, 5 cSt at 20oC and
lower calorific power 11,5 kWh/kg.
3. Light oil fuel with lower calorific power 11,2 kWh/kg.
If you wish to use an alternative fuel, please contact the manufacturer.
When liquid fuel is used, pay attention at the following:
•When filling the fuel tank, avoid any water or dust entering together with the fuel in the
tank.
•When the room temperature of the location where the boiler is mounted is lower than
0oC, it is recommended the use of a pre-heater.
3. BOILER MOUNTING
3.1. Transportation and delivery
The boiler is delivered complete with the metal covers, well packaged. The loading and
unloading of the boiler must be performed with a forklift or a crane. A special hook is provided
on the upper part of the boiler for lifting for models ENDS 180 upwards.
The boiler is heavy. Do not try to lift by hands or other unsuitable equipment.
Danger of injury! Perform all moves with extreme attention and care.
Remove the boiler packaging with attention. Keep the packaging material away from
children since it can be dangerous. After having unpacked everything, make sure that the
appliance is intact and undamaged. In case of doubt do not use the appliance and inform the
supplier.
The ENDS boiler is delivered with the following equipment already fitted and mounted:
▪Boiler steel body
▪Insulation mounted on the boiler body and tightened with plastic tapes
▪Metal covers mounted on the boiler body
▪Turbinators positioned inside the fire tubes
The following accessories are positioned inside the boiler body. Remove them carefully by
opening the middle door.
▪Cleaning tools
▪Control panel (optional)
In the documentation folder you will find:
▪Technical manual
▪Warranty leaflet

BOILER MOUNTING
8
3.2. Boiler room
3.2.1. General requirements
The boiler must be installed in a special and separate room. This room must be chosen so that
it offers easy access for fuel transport, air supply and exhaust gas evacuation. The doors of the
boiler room must be metallic, open outwards, and have at least 0,9 m width.
The boiler installation is prohibited in rooms with extensive dust, dangerous
gases, and moist spaces.
For the correct boiler function it is necessary that the boiler room has openings for natural
ventilation and combustion air supply. It is recommended that two different openings are used
for this purpose, positioned on opposite walls and diagonally to ensure good air circulation. The
cross section of the openings must be minimum 1/12 of the total surface of the boiler room.
The boiler room must be provided with a drainage channel. All safety devices must be
connected to this channel.
The boiler room must have an appropriate fire extinguishing system, according to the
regulations in force. In case that the building is designed with a fire alarm system, a smoke
detector must be positioned on top of every boiler.
The fuel storage is prohibited in the boiler room. If so, the storage must be separated from the
boiler with a non-flammable wall, and proper distanced from the boiler.
Fig 1. Boiler room ventilation and air supply

BOILER MOUNTING
9
3.2.2. Boiler room dimensions
The boiler must be placed on a horizontal plane, with adequate mechanical resistance to
support the boiler’s weight. The boiler must be positioned in the room in such a way so that it
is easily accessible from all the sides. The following dimensions are recommended (see Fig 2):
Distance from the front wall (N):
For boilers up to 100 kW –minimum 1,5 m
For boilers bigger than 100 kW –minimum 2 m
Distance from the rear wall (L):
Appropriate distance for maintenance access. Minimum 0,6 m.
Distance from side walls (M):
For boiler up to 300 KW –minimum 0,6 m
For boilers bigger than 300 kW –minimum 1 m
Boiler room height (H):
For boilers up to 70 kW –minimum 2 m
For boilers 70 to 230 kW –minimum 2,4 m
For boiler 230 to 400 kW –minimum 3 m
For boiler bigger than 400 kW –minimum 3,5 m
Distance between two boilers (P) must be at least 1m.
Fig 2. Recommended boiler room dimensions

BOILER MOUNTING
10
3.3. Chimney
The appropriate chimney installation is very important for the boiler’s efficient
and safe function!
The chimney must be made of a material which is corrosion resistant to the
condesate (plastic PP).
The chimney must be positioned if possible in the interior of the building. It must be vertical,
with no changes in the direction. The cross-section of the chimney can be round or
rectangular.
The chimney must be equipped with a cleaning door at its base. Also cleaning doors are
recommended where there are changes in direction. Tactical cleaning is recommended (every
year) for efficient boiler function.
Dimensioning and installation of the chimney must be made in conformity with the standards
and regulations applicable to condensing boilers.
3.4. Condensate drainage
During the boiler function a significant amount of condesate is produced. This
must evacuated to a pipe connected to the drainage. On the drainage pipe it is
obligatory to install a syphone and an initial filling hole, according to Error! Reference
source not found..
Before starting the boiler, pour a water inside the condensate evacuation pipe
through the filling hole.
The condensate drainage must comply with the following requirements:
▪Avoid of flue gas entering the drainage pipe
▪It must be water-tight and correctly dimensioned in order to avoid leakage of condensate
inside the boiler room
▪The condensate evacuation must not be made directly to the exterior, during winter ice can
be formed which will block the flow of the condensate
▪The upper generatrix of the drainage pipe must not be at a level higher than the bottom of
the chimney box
▪The boiler must be positioned on a support according to the drawing. If this is not possible,
the syphone should be buried underneath the floor level.
▪It is mandatory to install a filling hole of the syphone at the upper level of the drainage
pipe, and it must be left free in case of drainage blockage.
The condensate is slightly acidic. It is recommended that the condensate drainage
must be made of plastic materials, type PVC/PP which are not vulnerable to chemical
corrosion. In some cases, the water –drainage utility supplier may demand neutralizing of
the condensate before eliminating in the main drainage. These regulations should be
respected!
*Minimum syphone height according to standard ** Minimum height according to over-pressure at max power
Fig 3. Condensate drainage

BOILER MOUNTING
11
3.5. Mounting the burner
The ENDS boilers are overpressure boilers and it is necessary to take into account the static
pressure of counter-pressure in the combustion chamber to select the proper burner. The
burner must be selected according to the furnace power and the counterpressure. Always refer
to the burner manufacturer technical datasheet. The selected burner must be according to EN
267 for liquid fuel, and EN 676 for gas, and in conformity with the CE directive 2009/142/EEC.
The part of the fuel pipes, which are connected to the burner must have sufficient length and
must be flexible, in order to allow the opening of the boiler door.
The gap around the boiler flange is filled by fireproof ceramic material. The supply of fuel must
be adjusted at the nominal power of the boiler, by selection of the appropriate atomizer.
For the mounting of the burner on the boiler, you must take care of the following:
▪The burner must be well fixed on the special flange of the boiler. The four screws must be
fastened well, so that the burner is not loose on the boiler.
▪The sealing flange of the burner ensures insulation from combustion gas leaks. Take care
that it does not break.
▪The injection neck of the burner must be deep enough in the boiler, so that its edge reaches
deeper than the plate that carries the tubes. The burners with long injection neck are more
proper for boilers made of steel.
▪The burner must be positioned horizontally and parallel to the combustion chamber.
▪The position of the burner must be correctly aligned in connection with the center of the
combustion chamber. In this way a uniform flame is developed and a better distribution of
the thermal load is ensured.
▪The door must fit well on the sealing cord in order not to have combustion gas leaks.
▪The space between the injection neck of the burner and the door of the boiler must be
insulated with fireproof material.
▪The fireproof material of the door of the boiler must be replaced with new material, if it gets
damaged during the use.
The burner neck must penetrate inside the combustion chamber in a way that
the entire heat exchange surface of the fire chamber is performed uniformly by the
exhaust gas. If the neck of the burner is of very small size, the flame goes directly to
the fire tubes, a fact that results in excessive increase of the thermal strain of the
boiler.
Legend
1.
Burner
2.
Burner mounting flange
3.
Door insulation with fire proof material
4.
Insulation around the injection neck of the
burner
5.
Boiler door
6.
Ceramic insulation flange
7.
Sealing cord
8.
Burner injection neck
9.
Tube
10.
Boiler front plate

BOILER MOUNTING
12
Boiler type
D
D1
D2
A
B
M
S
Min burner
tube length
mm
ENDS 125
150
190
-
-
-
4 x M8
75
230
ENDS 200-400
185
224
310
-
-
8 x M10
75
270
ENDS 500-600
220
-
-
360
360
7 x M16
115
300
3.6. Mounting the control panel
To mount the panel, fasten the clips on the respective holes in the boilers cover, as shown in
the diagram. Place the panel over the clips until they are caught in the position.
The cable routes can be made through the inside of the boiler, through the respective holes in
the jackets.

BOILER MOUNTING
13
3.7. Door adjustment
The boiler door can be adjusted in all three axes. To adjust horinzontally and vertically, gently
losen the nuts and move the hinge into to oval hole. To adjust the depth, tighten the nut.
You can also change the direction of the door by changing the hinge position. Lower the door,
and change the position of the hinge and locking screw, as in diagram below.

INSTALLATION
14
4. INSTALLATION
4.1. Hydraulic connections
If a connection pipe is not used, it must be sealed before water fill!
4.2. Expansion vessel
The ENDS boiler is recommended to be connected with closed expansion vessel. The volume of
the expansion vessel is calculated according to the quantity of the water in the installation and
the static height. When choosing the expansion vessel, it should never be chosen marginal
size, but a size greater.
The expansion vessel should be connected at the return line of the boiler. Before the
installation, the pressure inside the expansion vessel should be regulated according to its
geometrical height from the point of its position up to the highest point of the installation. If
this height is lower than 8 m, then the pressure is adjusted at 0,8 bar. If the boiler room is on
a rooftop, the pressure on the tank should be adjusted at 0,5 bar.
The automatic filling valve must be installed next to the expansion tank and it is adjusted so
that, when the installation is cool, there is a pressure equal to the geometrical height
mentioned above plus 2 m. In areas where high-pressure distributing networks are present, a
pressure reducing gear must be placed.
Legend
T1
Boiler outet
T2h
Boiler inlet - high temerature
T2c
Boiler inlet - low temperature
T3
Chimney connection
T4
Drianage valve
T5
Safety connection
T6
Condensate draiange connection

INSTALLATION
15
4.3. Safety features
The boiler can be delivered as an optional with a safety kit, which shall be connected to the
corresponding safety connection pipe. The kit consists of a safety valve, an air relief valve and
a thermomanometer.
Additional safety equipment can be mounted on the outlet line, at a distance less than 1,5 m
from the boiler.
Fig 4. Boiler safety kit
4.4. Filling the system
After completing all the hydraulic connections, the circuit may be filled with water. After filling
the system, open the radiators air valves to get rid of the air in the installation.
Verify that the installation pressure is according to the technical feature of the boiler. The
pressure must be verified through the boiler’s manometer. An additional manometer should be
installed on the cold water inlet to verify the cold pressure, at the lowest point of the
installation, at a point close to the boiler.
The whole installation must remain under nominal pressure for at least 10 minutes. During this
period, check that all the connections are tight and there are no water leakages. Make sure
that during this period no pressure drop appears.
After firing the boiler, make sure the network functions properly at working temperature and
pressure.
The hardness of the mains water supply affects the boiler’s life span. It is
recommended to use a water softener if water hardness exceeds 15of.
Do not fill the system at the working pressure! When the boiler will be heated,
the water pressure will raise. Filling pressure must be at least 1 bar lower
than working pressure!
Boiler type
Connection*
ENDS 125
1 ½”
ENDS 200-600
2”
*Safety kit is not included. Contact the
manufacturer for further information.

INSTALLATION
16
4.5. Connection diagrams
Legend
1.
Boiler
RS
Ball valve
2.
Expansion vessel
CS
Non-return valve
3.
Boiler safety kit
RG
Drain valve
4.
Heating circuit pump
5.
HUW pump
6.
Y-filter
7.
Chemical filter
8.
Automatic water fill valve
9.
Filling line
10.
Hot water boiler
11.
Dual safety valve pressre/temperature
12.
Heating installation –radiators
13.
Heating installation –floor heating
IMPORTANT NOTE: When there is only one zone (high or low temperature) always
connect the return pipe to the Low temperature boiler inlet (T2c).

ELECTRICAL CONNECTIONS
17
5. ELECTRICAL CONNECTIONS
5.1. General instructions
All electrical connection must be performed by an authorized professional, in conformity with
the local regulations and the indications of this manual. Connections must be done according
to norms EN 60529 and EN 60335-1, and protection norms IP 40 and IP 44.
All wiring must be waterproof insulated. Exposed cables should be protected within plastic
channel. The main electrical supply of the boiler must be connected to an independent safety
of max 16A. The boiler room lighting must be on a separate circuit.
The user is obliged to connect the boiler to an efficient grounding system.
THERMOSTAHL ROMANIA SRL declines any liability for damage caused to
people, animals and goods, due to defects caused by faulty electrical
connections or lack of connecting the boiler to an efficient grounding system.
5.2. Control panel functions
Fig 5. EN-1 control panel
The general switch ON/OFF interrupts the electrical supply to all the devices.
The burner thermostat interrupts the burner function when the preset boiler temperature has
been reached. It is recommended that this temperature is set between 70-90oC. This
temperature should never be set below 55oC. The burner thermostat can control both one-
stage or two-stage burners, with a preset temperature difference between the two stages of
7oC.
The pump thermostat starts the circulation pump function at the preset temperature. It is
recommended that this temperature is set around 45-55oC.
The safety thermostat will interrupt electrical supply to the burner if the boiler temperature
reaches above 95oC. If so, it needs to be reset manually by unscrewing the plastic cover.
The burner and pump indication lamps follow the function of the corresponding devices.
The control panel offers the possibility to connect with a room thermostat. When the room
thermostat contact opens, the burner function stops.
Legend:
1.
Thermometer
2.
Burner thermostat
3.
Safety thermostat
4.
Pump thermostat
5.
General ON/OFF switch
6.
Pump function led
7.
Burner function led stage 1
8.
Burner function led stage 2

ELECTRICAL CONNECTIONS
18
Fig 6. EN-1 control panel wiring diagram
Legend:
M
General ON/OFF switch
1,2,3
Electrical supply ~230V/50Hz
TS
Safety thermostat
4,5,6
Pump connection
TB
Burner thermostat
7,8
Room thermostat connection
TP
Pump thermostat
9,10,11
Burner electrical supply
L
General function lamp
12,13
Burner stage 1
LB1
Burner indication lamp stage 1
14,15
Burner stage 2
LB2
Burner indication lamp stage 2
LP
Pump indication lamp
TR
Room thermostat
G
Grounding
Unscrew the control panel cover to have access to the connection terminals in the interior.
Connect the main electrical supply to the terminals 1, 2, 3 as indicated. The burner is
connected to the terminals 9, 10, 11 and the pump to the terminals 4, 5, 6. Connect the
burner command of stage 1 and of stage 2 to the terminals 12,13 and 14,15 respectively.
Between the terminals 7, 8 there is a jumper. If you want to connect a room thermostat,
remove the jumper and connect it to these two terminals.
Attention: The room thermostat must be a simple contact interrupter. It is not
allowed to connect a digital thermostat with an electrical signal output!

BOILER START-UP
19
6. BOILER START-UP
6.1. Initial lighting checks
Before you start the boiler, make the following checks:
▪Check that all the hydraulic connections and make sure they are tight. Make sure there is
no leakage or moisture on the pipes or other equipment.
▪Make sure that the connection with the chimney is air-tight and the chimney installation is
properly made.
▪Check that the controller bulbs are well inserted and secured in the boiler’s case.
▪Make sure that the pressure in the network is correct.
▪Check that the boiler pump and the central heating pumps function properly.
▪Make sure that the connection with the expansion vessel is correct and the expansion
volume is sufficient for the boiler. No valves should be installed between the boiler and the
expansion vessel.
▪Make sure the boiler’s separation valves are open.
▪Make sure that there is sufficient air supply and natural ventilation in the boiler room.
Do not store inflammable materials or fuel close to the boiler! Before you light
the boiler make sure the boiler room is clear and safe.
6.2. Start-up
To correctly start up the ENDS boiler, follow the next steps:
▪Make sure the control panel switch is set to OFF and the burner is stopped.
▪Make sure there is fuel in the fuel tank, or gas supply. Make sure all the connections guiding
fuel to the burner are tight.
▪Turn ON the control panel.
▪Turn the burner thermostat ON so that the burner will start function. Follow the burner
instruction in order to correctly start and set the burner.
▪Check the shape and color. Check the quality of the flame.
▪Set the thermostat as recommended.
6.3. Checks to carry after initial start-up
During the first start-up you need to carefully check the air-tightness of all the connections,
especially the doors and the connection with the chimney.
Check that the thermostats function properly and devices operate accordingly. Wait for the
boiler to reach the preset temperature and make sure the burner stops properly and the flame
falls down.
Check the temperature and pressure rise in the network. Make sure it is according to the
indications. Check if there is any water leakage in the network.
After a burning cycle is completed, check the situation inside the boiler. If the walls are too
black, it means that there is insufficient air supply. If there is condensation forming on the
boiler walls, it means that the pump operation starts at a low temperature. Make sure you set
the pump according to the indications and you install a return temperature protection system
as indicated.

BOILER START-UP
20
6.4. Combustion regulation
The flame from the burner must be thin and longitudinal and should not reach the side walls of
the fire chamber (nozzle projection angle=60º, possibly 45º for power over 140 Mcal/h).
The loading of the boiler with an atomizer smaller than the one that corresponds to the normal
heat value supply of the boiler is not recommended. The function of ENDS boilers is possible
up to 70% of their nominal heating output without any significant reduction on the outlet
temperature of the exhaust gases. Output below 70% is not allowed, since there may be
caused harmful corrosions due formation of condensations.
If during the performance measurements the temperature of exhaust gases is too low, there is
the possibility of increasing the by removing two or more turbinators (as required) from the
fire tubes that are placed at the bottom of the front tube plate.
During the combustion regulation of the burner on ENDS boiler type the following values must
be reached:
▪Burning of light oil: CO2= 12-13%, maximum temperature of burned gases outlet=220ºC
up to 180 kW and for boilers of bigger size 240ºC, soot rate=0-1 Bacharach.
▪Gas burning: CO2 max=10-12 %, maximum temperature of burned gases outlet=240ºC
▪Burning of heavy crude oil: temperature of burned gases outlet 220-260ºC, soot rate=0-1
Bacharach.
The measurements are carried out after the temperature of the water of the boiler has been
increased to 80-90ºC. For built chimneys the temperature of burned gases outlet must be at
least 150-170ºC.
GENERAL SUGGESTIONS:
▪CO: This indicates the excess air supply for good quality combustion. The more the air
increases, the CO% value reduces and the more the air reduces the CO% value increases.
▪SOOT RATE (according to Bacharach): This number indicates that in the exhaust gases
there are solid particles. If this number exceeds 2 on BH scale, you should check the
atomizer for possible defects or unsuitability for the burner and the boiler (make, type, and
diffusion angle). Generally, the BH number reduces by increasing the pressure of the valve.
In this case you should be careful because the fuel supply increases.
▪TEMPERATURE OF EXHAUST GASES: This is a value that expresses the heat losses through
the chimney to the environment. The higher the temperature is, the greater the heat loss is
and therefore the lower the efficiency.
NOTE: The current regulations of each country may require different adjustments from those
that have already been done and this requires observance of other parameters.