Fondital ANTEA Monothermal CTFS 40 Specification sheet

IST 03 C 983 - 01
ANTEA
Monothermal
CTFS 40
INSTALLATION, USE AND MAINTENANCE
EN
Translation of the
original instructions (in
Italian)

2
Dear Sirs,
thank You for choosing and buying one of our products. Please read these instructions carefully in order to properly install, operate, and
maintain the product.
WARNING
• We inform users that:
• Boilers shall be installed by an authorised company under the requirements set forth by the prevailing rules, in full compliance
with the prevailing regulations and standards.
• Anyone entrusting installation to an unqualified installer will be subject to administrative sanctions.
• Boilers must be maintained by qualified personnel only, under the requirements set forth by the prevailing rules.
We hereby inform you that certain models, versions and/or accessories relevant to the products this manual refers to, might not
be available in some countries.
Therefore, it is recommended to contact the manufacturer or the importer in order to get the necessary information about the
actual availability of such models, versions and/or accessories.
The manufacturer reserves the right to modify the products and/or its components as deemed necessary, in any moment and
without prior notice.
This instruction manual is available in two languages, Italian and English, without prejudice to the prevalence of Italian language
in case of differences in translation and/or dispute on construction of the text.

3
General notes for installing and maintenance technicians, and users
This instruction manual is an integral and essential part of the product. It shall be supplied by the installer to the user who shall keep it carefully
to consult it whenever necessary.
This document shall be supplied together with the equipment in case the latter is sold or transferred to others.
DANGER
This equipment has been manufactured to be connected to a room heating system and to a DHW distribution system.
Any other use shall be considered unsuitable and dangerous for people, animals, and/or property.
The equipment shall be installed in compliance with the prevailing standards and in accordance with the manufacturer's instructions specified
in this manual: the manufacturer will not be held responsible for injuries to people and animals and/or damages to property resulting from
an incorrect installation.
Damage and/or injury caused by incorrect installation or use and/or damage and/or injury due to non-observance of the manufacturer’s
instructions shall release the manufacturer from any and all contractual and extra-contractual liability.
Before installing the boiler, check that the technical data correspond to the requirements for its correct use in the system.
Check that the boiler is intact and it has not been damaged during transport and handling. Do not install equipment which is clearly damaged
and/or faulty.
Do not obstruct the air intake openings.
Only original accessories or optional kits (including the electric ones) are to be installed.
Properly dispose of the packaging as all the materials can be recycled. The packaging must therefore be sent to specific waste management
sites.
After removing the packaging, make sure that its elements (clips, plastic bags, foam polystyrene etc.) are note left within the reach of children
as they are potential hazard sources.
In the event of failure and/or faulty functioning, switch off the boiler. Do not attempt to make repairs: contact qualified technicians.
Original parts must be used for all repairs to the boiler.
Non-observance of the above requirements may affect the safety of the boilers and endanger people, animals and/or property.
WARNING
The boiler must be serviced periodically as indicated in the relevant section of this manual.
Appropriate boiler maintenance ensures efficient operation, environment preservation, and safety for people, animals and objects.
Incorrect and irregular maintenance can be a source of danger for people, animals and property.
The user is strongly advised to have the system serviced and repaired by qualified personnel, satisfying all prevailing law requirements, and
trained to properly carry out these operations.
In the event of long periods of inactivity of the boiler, disconnect it from the electrical power mains and close the gas cock. The electronic
antifreeze function will not be operative with the device disconnected from the electric power supply and gas cock closed.
Should there be a risk of freezing, add antifreeze: it is not advisable to drain the system as this may result in damage;use specific anti-freeze
products suitable for multi-metal heating systems.

4
DANGER
With gas fired boilers, take the following measures if you smell gas:
• Do not turn on or off electric switches and do not turn on electric appliances.
• Do not ignite flames and do not smoke.
• Close the main gas cock.
• Open doors and windows.
• Contact a Service Centre, a qualified installer or the gas supply company.
Never use a flame to locate a gas leak.
The boiler is designed for installation in the countries indicated on the technical data plate: installation in any other country may
be a source of danger for people, animals and/or property.
The manufacturer will bear no contractual and tortious liability for failure to comply with all the instructions above.

5
1. Instructions for the user .......................................................... 8
1.1 Control panel....................................................................................................................................................................................... 8
1.2 Interpreting boiler status from display indications.................................................................................................................... 10
1.3 Boiler operation .................................................................................................................................................................................. 11
1.4 Boiler shut-down ................................................................................................................................................................................ 14
1.5 Maintenance ....................................................................................................................................................................................... 15
1.6 Notes for the user................................................................................................................................................................................ 15
2. Technical features and dimensions ................................................. 16
2.1 Technical features .............................................................................................................................................................................. 16
2.2 Dimensions .......................................................................................................................................................................................... 18
2.3 Hydraulic diagram ............................................................................................................................................................................. 19
2.4 Operating data ................................................................................................................................................................................... 20
2.5 General characteristics...................................................................................................................................................................... 20
3. Instructions for the installer ....................................................... 21
3.1 Installation standards....................................................................................................................................................................... 21
3.2 Choosing where to install the boiler.............................................................................................................................................. 21
3.3 Positioning the boiler ........................................................................................................................................................................ 21
3.4 Installing the boiler ............................................................................................................................................................................ 23
3.5 Boiler room ventilation ..................................................................................................................................................................... 23
3.6 Air intake and ue gas venting system ......................................................................................................................................... 24
3.7 Checking combustion eciency..................................................................................................................................................... 31
3.8 Connection to gas mains.................................................................................................................................................................. 32
3.9 Hydraulic connections ...................................................................................................................................................................... 33
3.10 Connection to electrical mains ....................................................................................................................................................... 33
3.11 Connection to ambient thermostat (optional) ........................................................................................................................... 33
3.12 Installation and operation with Open Therm Remote Control (optional) ........................................................................... 34
3.13 Installation of the (optional) external probe and sliding temperature operation.............................................................. 34
3.14 TSP parameters................................................................................................................................................................................... 36
3.15 Filling the system................................................................................................................................................................................ 38
3.16 Starting up the boiler......................................................................................................................................................................... 39
3.17 Available head .................................................................................................................................................................................... 39
3.18 Wiring diagram................................................................................................................................................................................... 40
3.19 Adaptation to other gas types and burner adjustment............................................................................................................ 42
4. Testing the boiler................................................................ 44
4.1 Preliminary checks ............................................................................................................................................................................. 44
4.2 Switching on and switching o ...................................................................................................................................................... 44
5. Maintenance ................................................................... 45
5.1 Maintenance schedule...................................................................................................................................................................... 45
5.2 Combustion analysis......................................................................................................................................................................... 45
6. Malfunctions, possible causes and solutions ......................................... 46
6.1 Troubleshooting ................................................................................................................................................................................. 46

6
Fig. 1 Control panel ..............................................................................................................8
Fig. 2 Filler cock.................................................................................................................14
Fig. 3 Dimensions...............................................................................................................18
Fig. 4 Hydraulic diagram ........................................................................................................19
Fig. 5 Paper template ...........................................................................................................22
Fig. 6 0KITCONC00 (100/60 mm) ................................................................................................28
Fig. 7 Dimensions for coaxial pipe ...............................................................................................28
Fig. 8 0SDOPPIA13..............................................................................................................30
Fig. 9 Dimensions for split pipes.................................................................................................30
Fig. 10 Air intake and flue gas venting examples .................................................................................30
Fig. 11 Air intake and flue gas venting example ..................................................................................30
Fig. 12 Examples of flue gas testing points.......................................................................................31
Fig. 13 Connection to gas mains.................................................................................................32
Fig. 14 Thermoregulation curves ................................................................................................35
Fig. 15 Available head...........................................................................................................39
Fig. 16 Wiring diagram ..........................................................................................................40
Fig. 17 SIT 845 ..................................................................................................................43

7
Tab. 1 Adjustment specifications ................................................................................................20
Tab. 2 General specifications ....................................................................................................20
Tab. 3 Combustion specifications................................................................................................20
Tab. 4 Table indicating coaxial pipes 100/60 C12 type ............................................................................27
Tab. 5 Table indicating coaxial pipes 100/60 C32 type ............................................................................27
Tab. 6 Table indicating coaxial pipes 125/80 C12 type ............................................................................27
Tab. 7 Table indicating coaxial pipes 125/80 C32 type ............................................................................28
Tab. 8 Flue gas venting duct length and diaphragm diameter 80+80 .............................................................29
Tab. 9 Limits to be set for TSP parameters and default values in relation to boiler type (TSP0) - I ...................................36
Tab. 10 Limits to be set for TSP parameters and default values in relation to boiler type (TSP0) - II..................................37
Tab. 11 Relationship between "Temperature and Nominal resistance" for temperature probes.....................................41

8Instructions for the user
1. Instructions for the user
1.1 Control panel
2
1
10
5
6
87
C D
B
A
F
G
9
3 4
E
Fig. 1 Control panel
A. DHW setting (+/- DHW).
B. Parameter confirmation and information request.
C. Operating status selection.
D. Alarm reset and back to the starting page during parameter selection.
E. LCD display.
F. CH water temperature (+/- CH) and parameter settings.
G. Heating system water pressure gauge.

9
Instructions for the user
Ref. Description Steady on Flashing
1
Flue cleaning function
indicator
(for the installer)
Flue cleaning function active. Indicates that you are accessing the flue
cleaning function.
2 DHW indicator Boiler is in DHW mode. Displaying of the DHW temperature set-
point.
3 Parameter editing indicator
During parameter editing, the wrench
symbol stays on until the set datum is
confirmed.
When edited parameter value is confirmed.
4 Alphanumeric indicator Temperature, parameter values and fault
indication. Not used.
5 Central heating indicator Boiler is in heating mode. Displaying of the heating temperature set-
point.
6Fictitious ambient
temperature indicator Not used. Displaying of the fictitious ambient temperature set-point.
7 Boiler status indicator DHW and/or heating function active. Not used.
8 Flame lighting indicator Lit flame indication. Not used.
9 Parameter code indicator Displaying of the number of parameters or
of the burner power percentage. Not used.
10 Parameter indicator Indication of "parameter" inside the
parameter menu. Not used.

10 Instructions for the user
1.2 Interpreting boiler status from display indications
1.2.1 Normal operation
Boiler in STANDBY mode
Boiler in SUMMER mode
No active function
Flow temperature displayed
Boiler in WINTER mode
No active function
Flow temperature displayed
Boiler in CENTRAL HEATING ONLY mode
No active function
Flow temperature displayed
Boiler in SUMMER mode
Domestic hot water withdrawal
DHW temperature displayed
Boiler in WINTER mode
Domestic hot water withdrawal
DHW temperature displayed
Boiler in WINTER mode
CH function active
Flow temperature displayed
Boiler in CENTRAL HEATING ONLY mode
CH function active
Flow temperature displayed
1.2.2 Malfunction
To identify any malfunctions, refer to paragraph Troubleshooting on page 46.

11
Instructions for the user
1.3 Boiler operation
1.3.1 Switching on
DANGER
It is presumed that the boiler has been installed by a qualified installer, it has been commissioned and is ready to operate correctly.
• Open the gas shut-off cock.
• Turn the master switch installed ahead of the boiler to ON.
• The display turns on and indicates the function currently active (see Interpreting boiler status from display indications on page 10).
• Select the boiler operating mode: OFF/SUMMER/WINTER/CH ONLY (see button (C) in Fig. 1 Control panel on page 8).
• Set desired CH temperature (see CH function on page 11).
• Set desired DHW temperature (see DHW function on page 12).
• Set the desired room temperature on the ambient thermostat inside the home (if installed).
WARNING
After a prolonged period with the boiler not in use, and with LPG fired boilers in particular, some starting difficulty may be
encountered.
Before starting the boiler switch on another gas powered device (e.g. kitchen range).
Beware that even by following this procedure, the boiler might still experience some starting difficulties and shut down once or
twice. Press the“RESET” button to restore boiler operation.
1.3.2 Selecting the operating mode
To select the boiler operation mode press COperating mode selection.
Whenever button is pressed, the following modes are enabled in sequence: "SUMMER", "WINTER", "CH ONLY", "OFF".
"SUMMER" operating status
When the "SUMMER" mode is enabled, only the DHW production function is active.
"WINTER" operating status
When the "WINTER" mode is enabled, both DHW and CH functions are active.
"CH ONLY" operating status
When the "CH ONLY" mode is enabled, only the heating water production function is active.
"OFF" operating status
When the "OFF" mode is enabled, no function is active.
1.3.3 CH function
To set the heating water temperature, press +/- CH buttons.
The CH temperature setting range is from +35 °C to +78 °C.
During temperature setting, the symbol flashes on the screen and the CH current temperature setting is displayed.
When the CH system requests heat from the boiler, the LCD displays the CH symbol and the current CH flow water temperature.
The waiting time between one boiler ignition and the following one, used to prevent boiler frequent turning on and off, ranges between 0 and
10 minutes (default value: 4 minutes), and can be edited with the P11 parameter.
Should water temperature in the system fall below set minimum value, between 35°C and 78°C (default value 40°C) to be edited with the P27
parameter, the waiting time is reset and the boiler re-ignites.
The burner ON symbol shows while the burner is operating.

12 Instructions for the user
1.3.4 DHW function
Boiler electronics always gives priority to DHW over CH supply.
To set the domestic hot water temperature, press DHW +/- buttons.
During temperature setting, the symbol flashes on the screen and the DHW current temperature setting is displayed.
The burner ON symbol shows while the burner is operating.
The DHW temperature setting range is from +35 °C to +57 °C.
Available DHW litres per minute at the desired temperature depend on boiler heat output and water mains supply temperature, and can be
calculated according to the following formula:
l = DHW litre per min. = K/∆T
where:
K = 555
ΔT = hot water temperature – cold water temperature
E.g. when cold water temperature is 8°C and DHW is required at 38°C, the value of ΔT is:
∆T = 38°C - 8°C = 30°C
and the number of DHW litres per minute available at 38°C is:
l = 555/30 = 18,5 [litres per minute]
1.3.5 Freeze protection function
This boiler is fitted with a freeze protection system, which works when the following functions are activated: OFF/SUMMER/WINTER/CH ONLY.
DANGER
The freeze protection function only protects the boiler, not the whole heating system.
The central heating system can be effectively protected against icing by using specific anti-freeze products that are suitable for multi-metal
systems.
WARNING
Do not use anti-freeze products for car engines, and check the effectiveness of the product used over time.
In case burner cannot be ignited due to the lack of gas, the freeze protection functions are anyway enabled through the circulation pumps.
1.3.5.1 Flow freeze protection function
When the heating water temperature sensor detects a water temperature of +5 °C, the boiler switches on and stays on at its minimum heat
output until the temperature reaches +30 °C or 15 minutes have elapsed.
The pump continues to operate even if the boiler shuts down.
1.3.5.2 DHW plate exchanger freeze protection function
When the DHW temperature sensor detects a water temperature of +5°C, the boiler switches on and stays on at its minimum heat output until
the DHW temperature reaches +10°C or 15 minutes have elapsed (the deviating valve is in the DHW position).
During the DHW freeze protection operation the temperature detected by the flow probe is constantly checked, and in case it reaches +60 °C
the burner is switched off.
The burner is switched on again if the operation request in anti-freeze mode is still present and the flow temperature is below +60°C.
The pump continues to operate even if the boiler shuts down.

13
Instructions for the user
1.3.6 Anti-seize function
If the boiler remains inactive and connected to the power mains, the circulation pump and the deviating valve will be shortly enabled every
24 hours so as to avoid any shut-down.
The same applies to the relay which can be freely programmed whenever this latter is used to power a recirculation pump or a deviating valve.
1.3.7 Timed post-circulation function
After each central heating, DHW or freeze protection request, the pump continues to be powered for 30 seconds.
If a new central heating, DHW or freeze protection request is received during this period, the post-circulation function is cancelled in order to
fulfil the request.
1.3.8 Timed post-ventilation function
After each central heating, DHW or freeze protection request, the fan continues to work for 10 seconds.
If a new operating request is received during this period, the post-ventilation function is cancelled in order to fulfil the request.
1.3.9 Operation with external probe (optional)
Boiler can be connected to a probe measuring the external temperature (optional - not compulsory, supplied by the manufacturer).
Once the external temperature value is known, the boiler will automatically adjust the heating water temperature: increasing it as the
external temperature decreases and decreasing it as the external temperature increases. This will both improve room comfort and reduce fuel
consumption. The maximum temperature is respected all the same.
This boiler operating mode is called "sliding temperature operation".
Heating water temperature varies based on a programme written inside boiler electronic microprocessor.
When working with an external probe, the CH +/- buttons are no longer used to set heating water temperature, but to edit fictitious ambient
temperature, namely the desired theoretical temperature.
During temperature setting, the fictitious ambient temperature symbol flashes on the display and the value being set is shown.
For optimal curve adjustment, a position close to +20 °C is recommended.
For further details on "cruising temperature operation", refer to paragraph Installation of the (optional) external probe and sliding temperature
operation on page 34.
WARNING
Only original external temperature probes supplied by the manufacturer must be used.
The use of non-original external probes, not supplied by the manufacturer, may affect the operation of the external probe itself
and of the boiler.
1.3.10 Operation with (optional) remote control
The boiler can also be connected to a Remote Control (optional - not compulsory, supplied by the manufacturer) so as to manage several
boiler parameters, such as:
• boiler status selection.
• ambient temperature selection.
• CH system water temperature selection.
• DHW temperature selection.
• CH system activation time programming.
• boiler diagnostics display.
• boiler reset and other parameters.
To connect the Remote Control, see Installation and operation with Open Therm Remote Control (optional) on page34.
WARNING
Only use original Remote Control Units supplied by the manufacturer.
The use of non-original remote controls, not supplied by the manufacturer, may affect Remote Control and boiler operation.

14 Instructions for the user
1.4 Boiler shut-down
The boiler shuts down automatically if a malfunction occurs.
To determine the possible causes of malfunction (see Troubleshooting on page 46).
Below is a list of shut-down types and the procedure to follow in each case.
1.4.1 Burner shut-down
Fault code E01 is displayed flashing on the display in the event of burner shut-down due to missing flame.
If this happens, proceed as follows:
• check that the gas cock is open and light a kitchen gas ring for example to check the gas supply;
• once having checked if the fuel is available, press the Reset button to restore burner operation: if, after two starting attempts, the boiler still
fails to start and enters the shut-down mode again, contact a service centre or qualified personnel for maintenance.
WARNING
If the burner shuts down frequently, there is a recurring malfunction, so contact a service centre or a qualified service engineer.
1.4.2 Shut-down due to overheating
Fault code E02 is shown on the LCD display in the event of flow water temperature overheating. Contact a service centre or a qualified service
engineer to carry out the maintenance.
1.4.3 Shut-down due to incorrect air/flue gas system draught
The boiler is equipped with a safety device for flue gas exhaustion check.
Should an air/flue gas system malfunction occur, the control device will shut-down the boiler by interrupting the gas supply to the boiler and
the LCD will display the E03 code.
To resume the operation press Reset (see Fig. 1 Control panel on page 8).
In case of repeated stops, it is necessary to have the boiler and the air intake/flue gas venting ducts checked by a service centre or a qualified
service engineer.
1.4.4 Shut-down due to low water pressure
Fault code E04 is displayed on the LCD display in the event of shut-down triggered by the water pressure switch.
Fill the system by working on filler cock (A) (see Fig. 2 Filler cock).
Water pressure must be 1÷1.3 bars while the boiler is cold.
In order to restore water pressure, proceed as follows:
• Turn the filler cock anticlockwise to allow water to enter the boiler;
• Keep the filler cock open until the pressure gauge shows a value of 1÷1.3 bar;
• Turn cock clockwise to close it.
Should boiler shuts down frequently occur it means there is boiler malfunction in progress. Contact qualified personnel or an authorised
service centre for maintenance.
DANGER
Make sure you close filler cock (A) carefully after filling procedure is completed.
If you do not, when the pressure increases, the safety valve may activate and discharge water.
A
Fig. 2 Filler cock

15
Instructions for the user
1.4.5 Alarm due to temperature probe malfunction
The following fault codes are shown on the display in the event of burner shut-down due to a temperature probe fault:
• E05 for the CH probe: in this case the boiler does not work.
• E06 for the DHW probe; in this case, the boiler functions in central heating mode only, and the DHW function is disabled.
WARNING
In any case, contact a service centre or qualified personnel for maintenance.
1.4.6 Alarm due to (optional) Remote Control connection malfunction
The boiler recognises whether or not there is a Remote Control (optional, not compulsory).
If the boiler does not receive information from the Remote Control after the Remote Control itself is connected, the boiler attempts to re-
establish communication for 60 seconds, after which the fault code E31 is shown on the remote control display.
The boiler will continue to operate according to the settings on the touch screen and ignore the Remote Control settings.
WARNING
Contact a service centre or a qualified service engineer to carry out the maintenance.
The remote control can indicate faults or shutdown conditions and can also restore boiler operation after shutdown up to a maximum of 3
times in a 24 hour period.
If the maximum number of attempts is reached, fault code E99 is shown on the boiler display.
To reset error E99, disconnect and re-connect again boiler from/to power mains.
1.5 Maintenance
WARNING
The boiler must be serviced periodically as indicated in the relevant section of this manual.
Appropriate boiler maintenance ensures efficient operation, environment preservation, and safety for people, animals and objects.
Boilers must be maintained by qualified personnel only, under the requirements set forth by the prevailing rules.
1.6 Notes for the user
WARNING
The user may only access parts of the boiler that can be reached without using special equipment or tools. The user is not authorised
to remove the boiler casing or to operate on any internal parts.
No one, including qualified personnel, is authorised to modify the boiler.
The manufacturer shall not be held responsible in case of damage to people, animals, or property due to failure to follow the above
mentioned instructions.
If the boiler remains inactive and the power supply is switched off for a long time, it may be necessary to reset the pump.
This involves removing the casing and accessing internal parts, so it must only be carried out by suitably qualified personnel.
Pump failure can be avoided by adding to the water filming additives suitable for multi-metal systems.

16 Technical features and dimensions
2. Technical features and dimensions
2.1 Technical features
The boiler is equipped with an integrated gas atmospheric burner. The following models are available:
• CTFS sealed chamber, forced draught boiler with electronic ignition for heating and instantaneous DHW supply.
The following power rates are available:
• CTFS 40: with heat input of 41.0 kW
All models are equipped with electronic ignition and ionisation flame sensing device.
The boilers meet local applicable Directives enforced in the country of destination, which are stated on their rating plate.
Installation in any other country may be a source of danger for people, animals and property.
The key technical features of the boilers are listed below.
2.1.1 Manufacturing characteristics
• IPX4D electrically protected control panel.
• Integrated, modulating electronic safety board.
• Electronic ignition and ionisation flame detection device.
• Stainless steel, atmospheric burner that can run on several gases.
• Mono-thermal, high performance, copper heat exchanger.
• Twin shutter modulating gas valve.
• CH circulation pump with built-in air purging device.
• Safety pressure switch, preventing low water pressure operation.
• Air pressure switch
• Integrated, automatic by-pass.
• 10 litre expansion vessel.
• System filler cock.
• System water discharge tap.
• Heating flow water temperature probe.
• Safety thermostat on CH flow
• Stainless steel plate heat exchanger for DHW production.
• Motorised deviating valve.
• DHW priority flow switch.
• Domestic hot water temperature probe.
2.1.2 User interface
• Liquid crystal LCD interface showing the boiler operating status: OFF, SUMMER, WINTER and CH ONLY.
• CH water temperature setting buttons: 35-78 °C.
• DHW temperature setting buttons: 35-57 °C.
• System water pressure gauge.

17
Technical features and dimensions
2.1.3 Operating features
• Electronic flame modulation in CH mode, with timed rising ramp.
• Electronic flame modulation in DHW mode.
• Flow freeze protection function: ON 5°C; OFF 30°C or after 15 minutes of operation if CH temperature > 5 °C.
• DHW freeze protection function (CTFS): ON 5°C; OFF 10 °C or after 15 minutes of operation if DHW temperature > 5 °C.
• Timer-controlled flue cleaning function: 15 minutes.
• CH Maximum heat input parameter adjustment.
• Ignition heat input adjustment parameter.
• Ignition flame propagation function.
• CH thermostat timer: 240 seconds (adjustable).
• Heating pump post-circulation function in CH, freeze protection and flue cleaning modes: 30 seconds (adjustable).
• DHW post-circulation function: 30 seconds (adjustable).
• Post-circulation function for heating temperature > 78 °C: 30 seconds.
• Post-ventilation function after working: 10 seconds.
• Post-ventilation function for heating temperature > 95°C.
• Circulation pump and deviating valve anti shut-down function: 30 seconds of operation after 24 hours of inactivity.
• Ready for connection to an (optional) ambient thermostat.
• Ready for operation with an external probe (optional, supplied by the manufacturer).
• Ready for operation with an OpenTherm remote control (optional, supplied by the manufacturer).
• Anti-water hammer function: can be set from 0 to 3 seconds.
• DHW function priority.

18 Technical features and dimensions
2.2 Dimensions
346
400
700
108 93
17060
66 60 62 67 82 63
177
187
210 31
M
CGF
R
Fig. 3 Dimensions
MCH system flow (3/4”)
CDHW outlet (1/2")
GGas inlet (1/2”)
FCold water inlet (1/2")
RCH system return (3/4”)

19
Technical features and dimensions
2.3 Hydraulic diagram
MCG
8
7
6
5
4
3
2
1
9
10
11
12
18
14
15
FR
13
17
20
16
19
22
21
23
24
Fig. 4 Hydraulic diagram
1. Automatic by-pass
2. DHW temperature probe
3. Motorised 3-way valve
4. Modulating gas valve
5. Safety thermostat on CH flow
6. CH temperature probe
7. Burner
8. Ignition/detection electrode
9. Mono-thermal heat exchanger
10. Sealed combustion chamber
11. Flue gas extraction fan
12. Flue gas circuit safety pressure switch
13. Pressure testing point on flue gas duct
14. Air intake and flue gas venting duct
15. Pressure testing point on flue gas duct
16. Expansion vessel
17. 3-bar safety valve
18. System unloading cock.
19. Air-purging device
20. Minimum pressure switch
21. Circulation pump
22. Filler cock
23. Cold water flow switch with filter
24. Secondary plate exchanger
MCH system flow
CDHW outlet
GGas inlet
FCold water inlet
RCH system return

20 Technical features and dimensions
2.4 Operating data
Burner pressures reported in the following page must be verified after the boiler has been operating for 3 minutes.
Gas category: II2H3+
Fuel Gas mains pressure
[mbar] Nozzle [mm] Min pressure at the burner [mbar]
Max pressure at the
burner [mbar]
Natural gas G20 20 1,35 2,0 12,7
Butane gas G30 29 0,80 4,0 28,7
Propane Gas G31 37 0,80 5,4 36,3
Tab. 1 Adjustment specications
2.5 General characteristics
Description um CTFS 40
Burner nozzles no. 17
Nominal heat input kW 41,0
Minimum heat input kW 15,0
Max heat output kW 38,0
Minimum heat output kW 12,9
Minimum CH system pressure bar 0,5
Maximum CH system pressure bar 3,0
DHW circuit min. pressure bar 0,5
DHW circuit max. pressure bar 6,0
DHW specific flow rate (ΔT=25K) l/min 22,2
DHW specific flow rate (Δt=30K) l/min 18,5
Electric power supply – voltage / frequency V - Hz 230 - 50
Power mains supply fuse A 3,15
Maximum power consumption W 157
Pump absorption W 73
Electric protection rating IP X4D
Net weight kg 33,0
Natural gas consumption at maximum CH output (Value referred to 15 °C - 1013 mbar) cu. m/h 4,34
Butane gas consumption at maximum CH output kg/h 3,23
Propane gas consumption at maximum CH output kg/h 3,19
Maximum CH working temperature °C 83
Maximum DHW working temperature °C 62
Total capacity of expansion vessel l 10
Maximum recommended system capacity (Maximum water temperature 83°C, expansion vessel
pressure 1 bar) l 200
Tab. 2 General specications
Description um Max. output Min. output 30% load
Heat loss from the boiler casing % 1,82 1,49 -
Flue system heat loss with burner on % 5,48 12,31 -
Flue system mass capacity g/s 26,7 28,0 -
Flue temp. – air temp. °C 96,5 83,7 -
Absolute flue gas temperature upon safety thermostat
triggering °C 140
CO2 value (methane/butane/propane) % 6.6 / 7.8 / 7.8 2.2 / 2.6 / 2.6 -
Maximum heat output efficiency rating % 92,7 86,2 89,4
Efficiency rating (according to 92/42/EC) - * *
NOx emission class - 3
Tab. 3 Combustion specications