DOMUSA BioClass iC DX User manual

BIOCLASS iC DX
Biomass boiler
EN | INSTALLATION AND OPERATING INSTRUCTIONS

Thank you for choosing a DOMUSA TEKNIK heating boiler. Within the product
range offered by DOMUSA TEKNIK you have chosen Bioclass iC DX
model. With a suitable hydraulic installation and with a correct fuel, this boiler
will provide the ideal level of comfort for your home.
This manual forms an essential part of the product and it must be given to
the user. We recommend you read the warnings and recommendations in
the manual carefully, as they contain important information on the safety,
use and maintenance of the installation.
These boilers must be installed by qualified personnel only, in accordance
with the legislation in force and following the manufacturer’s instructions.
Commissioning of these boilers and any maintenance operations must only
be carried out by DOMUSA TEKNIK’s Authorised Technical Assistance
Services.
Incorrect installation of these boilers could result in damage to people,
animals or property, and the manufacturer will hold no liability in such cases.
DOMUSA TEKNIK informs all parties concerned that, in compliance with
section 1 of the first additional provision of Law 11/1997, the responsibility
for delivering packaging waste or used packaging for its proper
environmental management will be that of the final owner of the product. At
the end of its useful life, the product must be taken to a selected collection
point for electrical and electronic equipment or must be returned to the
distributor at the time of purchasing a new equivalent appliance. For more
detailed information on the collection schemes available, contact either the
collection facilities of the local authority or the distributor where the purchase
was made.

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4
BIOCLASS iC DX
ÍNDICE
1 LIST OF COMPONENTS ............................................................................................................... 6
2 INSTALLATION INSTRUCTIONS .................................................................................................. 8
2.1 LOCATION .............................................................................................................................................. 8
2.2 HYDRAULIC INSTALLATION .......................................................................................................................... 8
2.3 CYLINDER ....................................................................................................................................... 9
2.3 FUEL .................................................................................................................................................... 9
2.4 INSTALLING THE HOPPER .......................................................................................................................... 10
2.5 INSTALLATION OF A ROOM TEMPERATURE SENSOR OR THERMOSTAT ...................................................................... 11
2.6 ELECTRICAL CONNECTION ........................................................................................................................ 12
2.7 COMBUSTION PRODUCT REMOVAL ............................................................................................................... 12
2.8 BIO HYDRAULIC KIT INSTALLATION ............................................................................................................. 13
2.9 LOSS OF PRESSURE IN THE BOILER .............................................................................................................. 13
2.10 INSTALLATION WITH A BT BUFFER TANK (OPTIONAL) .................................................................................... 14
3 COMMISSIONING OF THE BOILER ............................................................................................ 17
3.1 PRIOR WARNINGS .................................................................................................................................. 17
3.2 FILLING THE INSTALLATION ....................................................................................................................... 17
3.3 INITIAL CALIBRATION OF THE FEED AUGER .................................................................................................... 17
3.4 COMMISSIONING ................................................................................................................................... 18
3.5 INSTALLATION DELIVERY .......................................................................................................................... 18
4 DIGITAL DISPLAY .................................................................................................................... 19
5 OPERATION ............................................................................................................................. 22
5.1 “ONLY HEATING” OPERATION .................................................................................................................... 22
5.2 OPERATING WITH A SANIT DHW TANK (OPTION) ........................................................................................... 22
5.3 BOILER TEMPERATURE SET POINT SELECTION ................................................................................................. 23
5.4 DHW SET TEMPERATURE SELECTION .......................................................................................................... 23
5.5 SELECTING THE SETPOINT TEMPERATURE OF THE BUFFER TANK (ONLY WITH BUFFER TANK) ......................................... 24
5.6 FUNCTIONING ACCORDING TO OUTDOOR TEMPERATURE CONDITIONS OTC (OPTION) ............................................... 24
6 OPERATING WITH BIO HYDRAULIC KITS (OPTIONAL) ............................................................... 25
7 OPERATION WITH A BT BUFFER TANK (OPTIONAL) .................................................................. 26
7.1 OPERATION WITH A TEMPERATURE SENSOR IN THE BT BUFFER TANK (P.08 = 2) ..................................................... 26
7.2 OPERATION WITH A CONTROL THERMOSTAT IN THE BT BUFFER TANK (P.08 = 4) .................................................... 27
8 OPERATING WITH LAGO FB OT+ REMOTE CONTROL (OPTIONAL) ............................................. 28
9 "ICONNECT" CONNECTIVITY .................................................................................................... 29
9.1 REQUIREMENTS FOR CONNECTING TO ICONNECT ............................................................................................. 29
9.2 BOILER REGISTRATION IN ICONNECT ........................................................................................................... 30
9.3 DESCRIPTION OF THE ICONNECT APPLICATION ............................................................................................... 31
9.4 ICONNECT APP MAP ............................................................................................................................... 31
10 USER MENU ........................................................................................................................... 33
10.1 ASHTRAY STATUS ................................................................................................................................. 35
11 SETUP MENU ......................................................................................................................... 36
11.1 TIMERS PROGRAMMING PROCESS .............................................................................................................. 37
11.2 HEATING TIME SCHEDULES ...................................................................................................................... 38
11.3 BOILER TIMER PROGRAMMING .................................................................................................................. 38
11.4 CVS SUCTION SYSTEM TIMER PROGRAMMING (CVS SUCTION SYSTEM OPTION ONLY) ............................................. 39
11.5 DHW RECIRCULATION FUNCTION TIMER PROGRAMMING (DHW TANK OPTION ONLY) ............................................... 39
11.6 TIME SETTING ..................................................................................................................................... 39
11.7 ASHTRAY EMPTY WARNING FUNCTION ........................................................................................................ 40
11.8 MANUAL SETTING OF FEED AUGER CALIBRATION ............................................................................................ 40
11.9 REGISTRATION OF THE BOILER IN ICONNECT ................................................................................................ 40
11.10 SCREEN CONTRAST SETTING .................................................................................................................. 40
12 CALIBRATION MENU .............................................................................................................. 41
12.1 FEED AUGER FILLING ............................................................................................................................. 4 2
12.2 FEED AUGER CALIBRATION ...................................................................................................................... 43
12.3 MANUAL SETTING OF FEED AUGER CALIBRATION ............................................................................................ 44
12.4 MANUAL ASH CLEANING ACTIVATION .......................................................................................................... 44
12.5 MANUAL CIRCULATION PUMPS ACTIVATION .................................................................................................. 44

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BIOCLASS iC DX
13 TECHNICAL MENU .................................................................................................................. 45
13.1 ENTRY AND SET THE ACCESS CODE ("COD", P.25) ......................................................................................... 48
14 BOILER'S SETUP PARAMETERS ............................................................................................... 49
14.1 BOILER MODEL (P.01) .......................................................................................................................... 49
14.2 BOILER HEAT OUTPUT (P.02, P.03) .......................................................................................................... 49
14.3 GENERAL FAN SPEED FACTOR (P.04) ......................................................................................................... 49
14.4 FUEL FOR IGNITION (P.05) ..................................................................................................................... 49
14.5 FUEL CONSUMPTION (P.06) .................................................................................................................... 49
14.6 FUEL TYPE (P.07) ................................................................................................................................ 49
14.7 MANAGING BT BUFFER TANKS (P.08, P.28, P.50) ........................................................................................ 50
14.8 AUXILIARY PARAMETER FOR FUEL SELECTION (P.26) ...................................................................................... 50
14.9 BOILER MINIMUM TEMPERATURE MODE (P.13, P.14) ..................................................................................... 50
15 HEATING CIRCUIT'S SETUP PARAMETERS ............................................................................... 51
15.1 HEATING PUMP POST-CIRCULATION TIME (P.15) ........................................................................................... 51
15.2 BOILER'S PUMP OPERATING MODE (P.18) ................................................................................................... 51
15.3 MINIMUM BOILER WATER PRESSURE (P.19) ................................................................................................. 51
15.4 MAXIMUM HEATING FLOW TEMPERATURE OF MIXED CIRCUITS (P.27) .................................................................. 51
15.5 TYPE OF ROOM TEMPERATURE DEVICE (P.46, P.47, P.48) .............................................................................. 51
15.6 ROOM TEMPERATURE HYSTERESIS (P.49) ................................................................................................... 52
15.7 ROOM TEMPERATURE CORRECTION (P.51, P.52, P.53) .................................................................................. 52
16 DHW CIRCUIT'S SETUP PARAMETERS ..................................................................................... 53
16.1 LEGIONELLA PROTECTION FUNCTION (P.17) ................................................................................................ 53
16.2 DHW RE-CIRCULATION FUNCTION (P.20 = 2) ............................................................................................. 53
17 ADDITIONAL FUNCTIONS ....................................................................................................... 54
17.1 CVS SUCTION SYSTEM CYCLE TIME (P.22) ................................................................................................. 54
17.2 RESET DEFAULT VALUES (P.24) ............................................................................................................... 54
17.3 PUMPS ANTI-LOCK FUNCTION ................................................................................................................... 54
17.4 ANTI-FROST FUNCTION .......................................................................................................................... 54
17.5 BOILER PRESSURE SENSOR FUNCTION ......................................................................................................... 54
17.6 CONNECTING THE LAGO FB OT+ REMOTE CONTROL ..................................................................................... 54
17.7 ROOM THERMOSTAT CONNECTION ............................................................................................................. 55
17.8 CONNECTING THE ROOM SENSOR .............................................................................................................. 55
18 MULTI-FUNCTIONAL RELAY (P.20) .......................................................................................... 56
18.1 BOILER ALARMS EXTERNAL SIGNAL (P.20 = 1) ............................................................................................. 56
18.2 DHW RE-CIRCULATION FUNCTION (P.20 = 2) ............................................................................................. 56
18.3 AUTOMATIC WATER FILLING FUNCTION (P.20 = 3) ....................................................................................... 56
19 CLEANING THE ASH DRAWER ................................................................................................. 57
19.1 SAFETY WARNINGS: .............................................................................................................................. 58
20 SAFETY LOCK-OUTS ............................................................................................................... 59
20.1 WATER OVERHEAT SAFETY LOCK-OUT (E-11) ............................................................................................... 59
20.2 FUEL ENTRANCE TUBE OVERHEAT SAFETY CUT-OUT (E-05)............................................................................... 59
20.3 LOW PRESSURE LOCK-OUT ...................................................................................................................... 60
21 SHUTTING DOWN THE BOILER ............................................................................................... 60
22 EMPTYING THE BOILER .......................................................................................................... 60
23 BOILER MAINTENANCE ........................................................................................................... 61
23.1 FREQUENCY OF MAINTENANCE OF THE BOILER AND CHIMNEY ............................................................................. 61
23.2 BURNER CLEANING PROCEDURE ................................................................................................................ 61
23.3 HEAT EXCHANGER CLEANING PROCEDURE .................................................................................................... 63
23.4 DRAINING THE CONDENSATE WATER .......................................................................................................... 64
23.5 BOILER WATER CHARACTERISTICS ............................................................................................................. 64
23.6 DHW CHARACTERISTICS ........................................................................................................................ 64
24 DIAGRAMS AND MEASUREMENTS ........................................................................................... 65
25 CONNECTIONS DIAGRAM ....................................................................................................... 67
25.1 BOILER ............................................................................................................................................. 67
25.2 BURNER ............................................................................................................................................ 68
26 ELECTRICAL DIAGRAM ........................................................................................................... 69
27 TECHNICAL DATA .................................................................................................................. 70
28 ALARM CODES ....................................................................................................................... 72

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6
BIOCLASS iC DX
1 LIST OF COMPONENTS
1. Pellet Auger.
2. Water pressure sensor.
3. DHW Inlet.
4. Boiler bulb holder sheath.
5. DHW bulb holder sheath.
6. Heat exchanger cleaning mechanism.
7. DHW outlet.
8. Safety valve.
9. Stainless steel Tank in tank system.
10. Heating expansion vessel.
11. Heat Exchanger.
12. Pellet inlet thermostat.
13. Ash pan.
14. Burner.
15. Air pressure sensor.
16. Viewport.
17. Boiler expansion vessel.
18. Filling loop.
19. Automatic air vent.
20. DHW safety valve.
21. Exhaust fan.
22. Chimney connection.
23. Drainage valve.

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BIOCLASS iC DX
Control components
17 18 20
16
19
1514
14. MENU touch button:
This button is used to access and browse through
the "User Menu".
15. Digital display:
It is the main boiler functioning display, on which
all the operating information, settings and values
appear. This display is also used to access the
appliance's user and service settings. In standard
operating mode (default display), the actual
boiler temperature is shown. If malfunction
occurs, an alarm code will appear on the digital
display instead of the temperature.
16. RESET touch button:
This button is used to restore functioning of the
boiler after a lock-out situation. Also it is used to
exit from any of the menus or parameters of the
boiler without saving it and to return to the
previous menu level.
17. ON touch button:
This button switches on and off the boiler.
18. Heating temperature touch button:
Use this button to select the desired boiler, room
temperature and other options related to the
heating installation. It can also be used to disable
the hot water function.
19. DHW set temperature touch buttom:
Use this bottom to select desired DHW SET
temperature. It can also be used to deactivate
DHW service.
20. SET touch button:
This button is used to access and browse through
the "Setup menu". Touch this button to access
the settings options.

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8
BIOCLASS iC DX
2 INSTALLATION INSTRUCTIONS
The boiler must be installed by personnel authorised by the Ministry of Industry, in compliance with the
applicable laws and regulations.
This boiler is suitable for heating water to a temperature below boiling point at atmospheric pressure. It
must be connected to a heating installation and/or a domestic hot water distribution network, which must
always be compatible with its performance and power.
This appliance must only be used for the purpose for which it has been expressly designed. Any other use
is considered unsuitable and therefore hazardous. The manufacturer shall not be considered liable under
any circumstances for damage caused by unsuitable, erroneous or irrational use.
Remove all the packaging and check the contents are complete. In case of doubt, do not use the boiler.
Contact your supplier. Keep the packaging elements out of reach of children, as they can be dangerous.
When you no longer wish to use the boiler, disable the parts that could be a potential source of hazard.
2.1 Location
The boiler must be installed in a sufficiently ventilated site, away from humidity. It must be located so
that the air grilles on the premises are not obstructed and normal boiler maintenance is possible even
if it is placed between items of furniture. One metre of free space must be left above the boiler for this
purpose. In the case of locating the boiler between furniture or walls, the reserve tank with the feeder
must be previously installed next to the boiler.
If you want to connect the boiler to the iConnect Internet platform or register it in the iConnect user
application, there must also be coverage of the home's Wi-Fi network in the room where the boiler
is located.
2.2 Hydraulic installation
The hydraulic installation must be made by qualified personnel. The applicable installation legislation is
to be complied with, and the following recommendations should also be taken into account:
• The inside of the installation piping should be thoroughly cleaned before switching on the
boiler.
• We recommend inserting cut-off valves between the installation piping and the boiler to
simplify maintenance tasks.
• Leave a free space around the boiler for carrying out any maintenance and repair operations.
• Drain valves and suitable devices for correctly bleeding the air from the circuit during the
boiler filling stage should be fitted.
• Install all the necessary safety elements (expansion vessel, safety valve, etc.) to comply with
the applicable regulations for the installation.
• If the boiler is installed at a lower height than the heating installation, it is recommendable
to create a siphon at the boiler outlet, to prevent the installation from heating up due to
natural convection when heating is not required.

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BIOCLASS iC DX
2.3 Cylinder
The special heat generator-cylinder conception and the regulation in force, oblige to comply with the
following requeriments:
• Secondary circuit (or DHW circuit) will need to have a 7 bar safety valve.
• Place dielectric sleeves on the appliance connections when the main pipe is cooper.
• Safety valve evacuation hose need to be led to a drain.
• When water supply pressure is over 7 bar, a pressure reducer needs to be installed.
NOTE: Bioclass iC DX boilers are equipped with a DHW safety group (tared at 7 bar),
dielectric sleeves and a DHW expansion veesel, with the objective of avoiding the
dripping from the DHW safety valve.
2.3 Fuel
Bioclass iC DX boiler must be fuelled by DIN PLUS certified wood pellet. The DIN PLUS or EN PLUS
A1 certificate assures that the fuel’s humidity levels and calorific value are ideal for optimum boiler
functioning. If this requirement is not complied with, DOMUSA TEKNIK’s guarantee of the appliance
will automatically be null and void.
The following aspects must be taken into account for the correct storage of fuel:
• Wood pellets should be stored in a room protected from humidity and weather. It is important
to create an air gap around the wood pellet bags to ensure good ventilation. These bags
should never be stored directly in contact with the ground and / or a wall.
• Wood pellets must be handled with care, as mixing them in bags can damage them.
• Wood pellets must be visually inspected before use in the boiler, to ensure the absence of
dust or pellets crushed in large quantities, which could cause a boiler malfunction.

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BIOCLASS iC DX
2.4 Installing the hopper
DOMUSA TEKNIK supplies a hopper for storing the pellets with the boiler. The tank is reversible and
can be mounted on either the left or right side of the boiler. It is also equipped with adjustable feet for
height regulation.
IMPORTANT: Ensure the height of the elliptical holes on the sides of the boiler and on
the hopper coincide, for correct insertion of the feed auger. To do this,
make the necessary adjustments for height (using the adjustment feet)
and depth (correctly positioning the hopper).

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BIOCLASS iC DX
2.5 Installation of a room temperature sensor or thermostat
The Bioclass iC DX boiler has a TA1 (J6) terminal strip (see "Connection Diagrams") ,prepared for the
connection of a device to measure the temperature conditions inside the house, which will the manage
the remote control of the heating circuit.
These devices will need to be suitably located within the home to be able to correctly manage the
comfort of the house. It is advisable to install them in an area of the home that has regular use (living
room, master bedroom, or similar), if possible avoiding rooms where heat or cold could be generated,
such as kitchens, bathrooms, refrigerated larders, etc. In turn, they must be installed at a medium
height and as far as possible from any source of heat or cold that could distort the temperature reading,
such as windows, fireplaces, stoves, etc.
Two different types of devices can be connected to the Bioclass iC DX boiler:
Room sensor
The room sensor measures the temperature inside the home and transmits it to the boiler which
displays it on the screen. The user will be able to select the desired setpoint temperature at any time
from the "User" menu, and will have the possibility of adjusting the desired comfort times for the
installation from the "Heating time programming"
(see "Configuration Menu") . The electronic control of
the boiler will manage the operating conditions to achieve the desired comfort and will modulate the
boiler temperature to optimise the operation and efficiency of the heating installation.
For the correct connection of a room sensor to the Bioclass iC DX boiler, proceed as follows:
• Unplug the boiler from the mains.
• Connect the room sensor, supplied with the boiler, to the TA1 (J6) terminal strip (see
"Connection Diagrams"). The bridge that connects the terminals of said strip must be
removed first.
• Reconnect the boiler to the mains power.
• The boiler comes factory configured for the connection of a "Room Sensor". If for any reason
this is not the case, for its correct configuration, parameter P.46 must be set to 1 (see
"Technical Menu").
• The electronic control allows correcting the value measured by the room temperature sensor,
using parameter P.51. To make this adjustment correctly, first of all it should be waited a
minimum of 10 minutes for the measured value to stabilize (without touching the room
temperature sensor).
Room thermostat
A room thermostat connected to the boiler will activate and deactivate the heating demand depending
on its setting. In addition, if it has a time programming (chronothermostat), the user can set the desired
heating operating periods.
For the correct connection of a thermostat to the Bioclass iC DX boiler, proceed as follows:
• Unplug the boiler from the mains.
• Connect the room thermostat to the terminal block TA1 (J6) (see "Connection Diagrams"),
having previously removed the bridge that connects the terminals of said strip.
• Reconnect the boiler to the mains power.
• Lastly, the boiler must be configured to operate with "Room Thermostat", setting parameter
P.46 to 0 (see "Technical Menu").

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BIOCLASS iC DX
2.6 Electrical Connection
The boiler is equipped for connection at 230 V~, 50 Hz. The socket should have an appropriate
earth connection.
The terminal strip J2 includes terminals for connecting the feed auger, whereas the terminal strip J3
includes terminals for connecting the circulation pump of the boiler (BC).
IMPORTANT: Before carrying out any work on the boiler's electrical installation, always
ensure it is disconnected from the mains.
2.7 Combustion product removal
Bioclass iC DX boiler is a biomass boiler and it is essential for it to be connected to a flue, i.e. a smoke
duct able to create a pressure drop (which in this case should be between 0,05 and 0,20 mbar), in
compliance with the applicable laws to this regard.
The combustion product exhaustion ducts must be installed by qualified personnel and must comply
with the regulations in force. For the flue to create a pressure drop, the following recommendations
should be taken into account:
• It should be suitably insulated.
• It should be independently located, with a separate flue for each boiler.
• It should be vertical, avoiding any angles greater than 45º.
• It should always have the same diameter. It is recommendable for it to be circular, and never
any narrower than the boiler outlet.
• It is obligatory to install a fume inspection plate with condensation collection, to remove the
condensation generated in the flue. Otherwise, the condensation may reach the inside of the
boiler and cause irreparable damage, which would not be covered by DOMUSA TEKNIK’s
guarantee. The condensation pipe should lead to a drain outlet, as a large amount of water
may be generated. This connection must be made in compliance with the regulations for
draining off condensation water to the drain network.

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BIOCLASS iC DX
2.8 BIO hydraulic kit installation
In option a BIO hydraulic kit, within the kits range offered by DOMUSA TEKNIK, could be connected
to Bioclass iC DX boiler. In that way the features of the boiler will be increased.
Look at the following instructions for a correct installation:
• Unplug the boiler and the hydraulic kit from the main power supply.
• Connect the communication between the boiler and the hydraulic kit, connecting the J4
electrical strips of both devices (see "Connection Diagrams"), for which, you must use a 2-
wire electrical hose and the 2-way strip (+ A / -B) supplied together with the Kit (in the
documentation bag). To assure the correct running of BIO hydraulic Kit it is essential
to respect the polarity of the connection. The same wire must be connected to the
+A terminal of the boiler as well as to the +A terminal of the hydraulic Kit. Same
operation with the –B terminals.
• After connecting the communication between the boiler and the hydraulic Kit, plug the BIO
hydraulic Kit to the main power supply. It is recommended to plug the Kit before the boiler
to assure a correct running of the system.
• Plug the boiler to the main power supply.
Follow the instructions provided with the kit to assure a correct installation.
IMPORTANT: It is compulsory to respect the polarity of both wires of the cable to assure
a correct running of BIO hydraulic Kit.
NOTE: In order to have a correct communication between the boiler and the BIO Hydraulic
Kit, it is necessary to connect first the Kit to the mains and then the boiler.
2.9 Loss of pressure in the boiler
To correctly size the hydraulic installation and choose the correct pump operation and pump operation
curves, the pressure loss caused by the boiler should be taken into account. The following graph
describes the pressure loss curves according to the model of Bioclass iC DX boiler:
Pérdida de carga en caldera
0
1
2
3
4
5
6
7
00,511,522,5
Q(m3/h)
H(m)
i
C
DX 1
8
i
C
DX 2
5
Loss of pressure in the boiler

EN
14
BIOCLASS iC DX
2.10 Installation with a BT Buffer Tank (Optional)
The Bioclass iC DX boiler can be accompanied by a BT Buffer Tank during the installation from the
wide range offered by DOMUSA TEKNIK, which may increase the benefits provided by the boiler in the
heating service.
For this reason, the electronic control of the boiler is equipped with an input for a temperature sensor
or a temperature thermostat (Sbt; terminals 18-19 on connection strip J7) and a circulation pump
output (Bbt; terminals N-7 on the connection strip J2) dedicated exclusively to managing the heating
of the buffer tank. Using these control elements of the boiler you will be able to manage 2 different
modes of buffer tank hydraulic installation. The installation type will be selected using parameter P.08
in the "Technician" menu on the control panel.
The boiler is supplied with this installation option disabled. To enable it, the electrical resistance (Rbt)
connected between terminals 18 and 19 of connection strip J7
(see "Connection Diagram") must be
disconnected and replaced with a temperature sensor (supplied as an option by DOMUSA TEKNIK) or
a control thermostat installed in the BT buffer tank. After disconnecting the resistance in the
"Technician" menu of the control panel, parameter P.08 must be enabled, via which you can select the
installation mode desired.
The following sections describe in detail the hydraulic and electrical connection characteristics for each
installation mode.

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BIOCLASS iC DX
2.10.1 Installation with Sanit DHW tank before BT tank and control by temperature
sensor (P.08 = 2)
In this installation mode, all heating circuits must be hydraulically connected to the BT buffer tank,
upstream from the BT buffer tank. The BT tank feed pump (Bbt) will be installed as indicated in the
following hydraulic diagrams. The temperature of the BT tank is controlled and managed by a
temperature sensor (Sbt) immersed in the buffer tank and electrically connected to the boiler. The
temperature sensor is optionally supplied by DOMUSA TEKNIK and it can be purchased at any
warehouse specialized in heating supplies.
Heating
installation
After the hydraulic installation of all the system components, proceed as follows to carry out the correct
electrical connection of the BT buffer tank to the Bioclass iC DX boiler:
• Unplug the boiler from the mains power.
• Disconnect the electrical resistance (Rbt) connected between terminals 18 and 19 of
connection strip J7
(see "Connection Diagram") .
• Connect the BT tank temperature sensor (supplied optionally) to the sensor connection strip
J7 (Sbt; terminals 18 and 19)
(see "Connection Diagram") .
• Insert the temperature sensor bulb in the bulb-holder sheath provided in the buffer tank.
• Connect the BT tank feed pump to the component connection strip J2 (Bbt; terminals N and
7)
(see "Connection Diagram") .
• Connect the boiler to the mains power.
• Using the control panel, access parameter P.08 in the "Technician" menu
(see "Technician
Menu")
and set the value to "2".
• After that, if it is necessary, set also the parameter P.28 "BT buffer tank temperature
hysteresis".
Once the hydraulic and electrical connection described above has been completed, to adjust and
configure the BT buffer tank operation, carefully read the section
"Operation with a BT buffer tank" in
this manual.

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BIOCLASS iC DX
2.10.2 Installation with BT tank and control by thermostat (P.08 = 4)
In this installation mode, all heating circuits must be hydraulically connected to the BT buffer tank. In
other words, the BT buffer tank, the BT tank feed pump (Bbt) will be installed as indicated in the
following hydraulic diagrams. The temperature of the BT tank is controlled and managed by a
thermostat (Tbt) installed and immersed in the buffer tank and electrically connected to the boiler. The
temperature control thermostat is not supplied by DOMUSA TEKNIK but can be purchased at any
specialist central heating supplies warehouse.
Heating
installation
After the hydraulic installation of all the system components, proceed as follows to carry out the correct
electrical connection of the BT buffer tank to the Bioclass iC DX boiler:
• Unplug the boiler from the mains power.
• Disconnect the electrical resistance (Rbt) connected between terminals 18 and 19 of
connection strip J7
(see "Connection Diagram") .
• Connect the NC contact (normally closed) on the BT tank control thermostat on the sensor
connection strip J7 (Sbt; terminals 18 and 19)
(see "Connection Diagram") .
• Insert the thermostat bulb into the bulb-holder sheath provided in the buffer tank.
• Connect the BT tank feed pump to the component connection strip J2 (Bbt; terminals N and
7)
(see "Connection Diagram") .
• Connect the boiler to the mains power.
• Using the control panel, access parameter P.08 in the "Technician" menu
(see "Technician
Menu")
and set the value to "4".
Once the hydraulic and electrical connection described above has been completed, to adjust and
configure the BT buffer tank operation, carefully read the section
"Operation with a BT buffer tank" in
this manual.

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BIOCLASS iC DX
3 COMMISSIONING OF THE BOILER
3.1 Prior warnings
Repair and maintenance of the boiler must be carried out by a qualified professional, authorised by
DOMUSA TEKNIK. For optimum functioning and conservation of the boiler, it should be serviced
annually.
Carefully read this instruction manual and keep it in a safe, easily-accessible place. DOMUSA TEKNIK
will not be liable for any damages caused by failure to follow these instructions.
Before any servicing, disconnect the boiler from the mains.
3.2 Filling the installation
The hydraulic installation must include a disconnector key, drain valves and the necessary hydraulic
components for correctly filling the installation. Before filling the primary circuit, make sure that
the secondary (DHW circuit) is full.
To fill the installation, open the fill valve until the parameter
“Water pressure” of “User Menu” shows a
pressure of 1 - 1.5 bars. The installation must be filled slowly, bleeding the air from the water circuit
using the drain valves provided on the same. Close the fill valve after filling.
Bioclass iC DX boilers have a pressure sensor for controlling the pressure of the installation. If the
installation does not have the minimum pressure set at P.19 parameter of
”Technical Menu” (by default
0.5 bar), a low pressure alarm will appear ("E-19").
IMPORTANT: Switching on the boiler with no water inside could result in serious damage.
3.3 Initial calibration of the feed auger
Bioclass iC DX boiler is equipped with a feed auger to supply the fuel. Follow the instructions described
in
"Installing the hopper” section to install it correctly. Due to diversity of feed augers and the range of
different hoppers, it is needed to calibrate the feed auger minimum twice to assure the correct running.
Follow the instructions described in “
Feed auger calibration” section of “Setup menu” to assure a correct
calibration.

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BIOCLASS iC DX
3.4 Commissioning
In order for the guarantee to be valid, the boiler must be commissioned by personnel authorised
by DOMUSA TEKNIK. Before beginning the commissioning, the following must be complied with:
• The boiler must be plugged in to the mains.
• The installation must be filled with water (the pressure must be between 1 and 1.5 bar).
• The hopper must be filled with fuel.
The commissioning sequence is as follows:
• Check the flue is correctly installed using a condensation inspection tap and a draught
stabiliser.
• Check the hopper and the feed auger are correctly installed. The feed auger must be
calibrated for a correct boiler functioning (See
“Calibrating the feed auger” ). Check the
right type of fuel is being used (wood pellet must be DIN PLUS).
• If the installation has flow and return valves, check they are open.
3.5 Installation delivery
After commissioning, the Technical Assistance Service will explain to the user how the boiler functions,
making any observations they consider relevant.
The installer is responsible for clearly explaining to the user the functioning of any control or regulation
device forming part of the installation but not supplied with the boiler.
Upon delivery of the boiler, the user receives the following documents:
• The boiler installation and operation manual.
• Combustion analysis performed during commissioning.
• The commissioning sheet.

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BIOCLASS iC DX
4 DIGITAL DISPLAY
Bioclass iC DX boiler is equipped with a digital touch display for viewing and adjustment of the different
boiler settings. The display has various display areas where different icons and numbers appear to indicate
the different status of the boiler.
A B E
J
G HC FD
I
A Boiler status: Heating function enabled.
DHW production enabled.
B Icon for flame detection: Flame detected.
C Timer icons:
It is displayed when the real time is inside “ON” programmed period.
It is displayed when actual time is inside “OFF” programmed period.
When any screen is displayed it relates to the display of actual time, programming, etc.
D Scale marking bar: The meaning can change depending on the parameter displayed:
Time scale: Used to indicate values or settings related to the time and/or time programming:
Lux scale: Used to indicate the lux level read by the flame sensor:
Ash Scale: Used to indicate the level of ash:
E Numerical digits.
F Alarm icons: Warning.
Boiler lock-out.

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BIOCLASS iC DX
G Special functions icons:
Anti-frost function: This icon blinks when the boiler's anti-frost function is activated.
Technical icon: It is displayed when any of the boiler's technical parameter on the
"Technical Menu" or "Setup menu" is displaying or modifying.
H Auxiliary icons.
Value or setting related to a temperature is shown by the numerical digits.
EXT Value or setting related to the outside temperature is shown by the numerical digits.
INT Value or setting related to the room temperature are shown by the numerical digits.
bar Value or setting related to the boiler water pressure is shown by the numerical digits.
I Heating zone icons:
Display of any value or parameter related to Zone 1 heating.
Display of any value or parameter related to Zone 2 heating.
Display of any value or parameter related to Zone 3 heating.
J Operating mode icons:
Display of any value or parameter related to the inside temperature of the home or
parameters related to room sensors or remote controls.
It is displayed when a value or setting related to OTC operating mode is shown by the
numerical digits.
It is displayed when the direct heating circuit nº 1 demand is activated or when a value or
setting related to this circuit is shown by the numerical digits.
It is displayed when the direct heating circuit nº 2 demand is activated or when a value or
setting related to this circuit is shown by the numerical digits.
It is displayed when the mixing heating circuit nº 1 demand is activated or when a value or
setting related to this circuit is shown by the numerical digits. The arrows appear according
to the 3 way mixing valve of the circuit activation mode. The upper arrow indicates that the
hot channel of the valve is opening, and the lower arrow indicates that the hot channel of
the valve is closing.
It is displayed when the mixing heating circuit nº 2 demand is activated or when a value or
setting related to this circuit is shown by the numerical digits. The arrows appear according
to the 3 way mixing valve of the circuit activation mode. The upper arrow indicates that the
hot channel of the valve is opening, and the lower arrow indicates that the hot channel of
the valve is closing.
It is displayed when any value or setting related to the boiler and/or the burner is
shown by the numerical digits.
It is displayed when a value or setting related to DHW tank is shown by the numerical digits.