Fondital Tahiti Dual hc Quick start guide

INSTALLATION,
USE AND MAINTENANCE
TAHITI DUAL
HC - HR
GB
MADE IN ITALY
High quality Italian product
Gas fired wall Mounted condensing boiler
Tahiti Dual 24 - 32 kW Combi (HC)
Tahiti Dual 24 - 32 kW Regular (HR)

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Natural Gas
Fondital Tahiti Dual HC 24 kW Line Combi (HC)
G.C.N° 47 309 04
Fondital Tahiti Dual HR 24 kW Line Regular (HR)
G.C.N° 47 309 05
Fondital Tahiti Dual HC 32 kW Line Combi (HC)
G.C.N° xx xxx xx
Fondital Tahiti Dual HR 32 kW Line Regular (HR)
G.C.N° xx xxx xx
Benchmark places responsibilities on both manufacturers and installers. The purpose is to ensure that customers are provided with the
correct equipment for their needs, that it is installed, commissioned and serviced in accordance with the manufacturer’s instructions by
competent persons and that it meets the requirements of the appropriate Building Regulations. The Benchmark Checklist can be used to
demonstrate compliance with Building Regulations and should be provided to the customer for future reference.
Installers are required to carry out installation, commissioning and servicing work in accordance with the Benchmark Code of Practice
which is available from the Heating and Hotwater Industry Council who manage and promote the Scheme.
Visit www.centralheating.co.uk for more information.

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Dear Customer,
Thank You for choosing and buying one of our boilers.
Please read these instructions carefully in order to properly install, operate, and maintain the equipment.

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1. General information for fitters, maintenance technicians and users
1.1. General warnings
This INSTRUCTION MANUAL, which is an integral and indispensable part of the product, must be handed over to the user by the in-
staller and must be kept in a safe place for future reference. The manual must accompany the boiler should it be sold or its possession
transferred. Following to the boiler installation, the tter is to advise the user about boiler operation and its safety devices. This Manual
must be left along with the Benchmark commissioning booklet with the boiler as Regulation 29 of the HSC Gas safety (installation and
use) Regulations 1998.
This boiler is designed for connection to a domestic heating or hot water system.
Any other use is deemed as improper and as such dangerous. Under no circumstances will the manufacturer be held
responsible for damage or injury to persons or animals caused by errors in the installation and/or use of the appliance,
or through non-compliance with current local and national standards and/or the manufacturer’s instructions.
The boiler must be installed by qualied personnel, in compliance with applicable laws and standards and according to the
manufacturer’s instructions given in this manual.
In GB, the installation must be carried out by a Registered Installer. To check for authorised qualied engineers please contact
CORGI 01256 372400. It must be carried out in accordance with the relevant requirements of the:
• GasSafetyRegulations;
• TheappropriateBuildingRegulationseitherTheBuildingRegulation,TheBuildingRegulations(Scotland),BuildingRegulations 
 (NorthernIreland);
• TheWaterFittingsRegulationsorWaterBylawsinScotland;
• ThecurrentI.E.E.WiringRegulations.
Wherenospecicinstructionsaregiven,referenceshouldbemadetotherelevantBritishStandardsCodeofPractice.
InIE,theinstallationmustbecarriedoutbyacompetentPersonandinstalledinaccordancewiththecurrenteditionofI.E.813
“DomesticGasInstallations”,thecurrentBuildingRegulationsandreferenceshouldbemadetothecurrentETCIrulesforelectrical
installations.
The commissioning of the boiler and any subsequent works carried out on the appliance must be effected by an appropriately qualied
technician or an approved Fondital Helpline Service Centre.
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 relieve 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 damaged
and/or faulty. In case of doubt, do not attempt to use the product but refer to the supplier. Packing materials (cardboard box, wooden
crate, nails, staples, plastic bags, polystyrene, etc.) must not be left within reach of children in that these items represent a potential
hazard and must be disposed of in a responsible manner.
Do not obstruct the air intake or ue exhaust grills and terminals.
Only manufacturer approved and supplied accessories or optional kits (including 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 specic waste
management sites.
In the event of failure and/or malfunction, shut down the system. Do not interfere with or attempt any repairs. Call for professionally
qualied technical assistance only. Fondital helpline UK 08700 34 8820.
Any warranty repairs to the appliance must be carried out exclusively by the manufacturer’s authorised service centre using original
spare parts. Non-observance of the above requirements may affect the safety of the boilers and endanger people, animals and property.
The manufacturer, in order to guarantee efcient and correct functioning of the equipment, recommends the boiler to be serviced and
repaired by an authorized Service Centre which is best trained for the purpose.
Before carrying out any cleaning or maintenance operations, disconnect the appliance from the mains electricity supply by switching off
at the main switch and/or any other isolating device.
Routine boiler maintenance is to be performed according to the schedule indicated in the relevant section of this
manual. Appropriate boiler maintenance ensures efficient operation, environment preservation, and safety for people,
animals and objects.
Intheeventoflongperiodsofinactivityoftheboiler,disconnectitfrompowermainsandclosethegastap.Warning!
Whenpowermainsaredisconnected,boilerelectronicanti-freezefunctionwillnotbeoperative.
Shouldtherebeariskoffreezing,addanti-freeze:itisnotadvisabletoemptythesystemasthismayresultindamage;usespecic
anti-freeze products suitable for multi-metal heating systems.

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Should 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 tap;
- open doors and windows;
- contact a Service Centre, a qualified installer or the gas supply company.
Never use flames to detect gas leaks.
NATIONAL GRID GAS EMERGENCY 0800 111 999
The boiler is designed for installation in the country indicated on the technical data plate: installation in any other
country may be source of danger for people, animals and objects.
The “operating instructions” of this manual must be read carefully as it provides information on the operating and the operating limits of
the appliance.
This appliance must be used exclusively in an un-vented central heating system.
The warnings contained in this chapter have been written for the appliance user, the installer and the service engineer.
1.2. Product conformity
FONDITAL S.p.a. declare that all its products are manufactured to a high specication and in compliace with the relevant standards.
AllFONDITALboilersareCEcertiedandpossesstechnicalandfunctionalcharacteristicsthatcomplywiththefollowingstandards:
UNIEN297forGAS-FIREDCENTRALHEATINGBOILERSTYPEBOFNOMINALHEATINPUT≤70kW
EN483forGAS-FIREDCENTRALHEATINGBOILERSTYPECOFNOMINALHEATINPUT≤70kW
UNIEN677forGAS-FiredCENTRALHEATINGBOILERS.SPECIFICREQUIREMENTSFORCONDENSINGBOILERSWITHNOMINAL
HEATINPUT≤70kW
Gas red boilers also comply with the following directives:
GASAPPLIANCESDIRECTIVE90/396CEEforCEcompliance
LOWVOLTAGEDIRECTIVE2006/95CE
BOILEREFFICIENCYDIRECTIVE92/42CE
ELECTROMAGNETICCOMPATIBILITYDIRECTIVE89/336CE
The materials used such a copper, brass, stainless steel, etc. form a compact, homogeneous, highly functional unit that is easy to install
and simple to operate. In its simplicity, the wall-mounted appliance is equipped with all the appropriate accessories required to make it a
fully independent boiler capable of satisfying domestic hot water production and central heating needs. All boilers are fully inspected and
are accompanied by a quality certicate, signed by the inspector, and a guarantee certicate. This manual must be kept in a safe place
and must accompany the boiler at all times.
FONDITAL S.p.a. will not be held responsible for any misinterpretation of this manual resulting from the inaccurate translation of
same.
FONDITAL S.p.a. will not be held responsible for the consequences in the case of non observance of the instructions contained
in this manual or in the case where actions not specifically described herein are undertaken.
FONDITAL S.p.a. declare that no substances harmful to health are contained in the appliance or used during appliance
manufacture and have not used or intend to use any of the following substances in the manufacture of Fondital heating
products:
- Asbestos
- Mercury
- CFC’s
It is a condition of the manufacturers warranty that the Benchmark Commissioning Checklist is fully
completed and left with the appliance.

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CONTEST
1.General information for fitters, maintenance technicians and users pag. 4
1.1. General warnings pag. 4
1.2. Product conformity pag. 5
2.Instructions for the user pag. 7
2.1 Control panel pag. 7
2.2 Operating the boiler pag. 9
2.2.1. Switching on pag. 9
2.2.2. CH function pag. 9
 2.2.3.DHWfunction pag. 10
 2.2.4.ANTI-FREEZEfunction pag. 10
 2.2.5.PUMPANDTHREE-WAYVALVEANTI-SEIZEFUNCTION pag. 10
 2.2.6.Externalprobeoperation(optionalequipment) pag. 10
2.3.Boiler lockout pag. 11
2.3.1. Burner lockout pag. 11
2.3.2. Shut-down due to overheating pag. 11
2.3.3. Shut-down due to inadequate air/ue gas draught pag. 11
2.3.4. Shut-down due to low water pressure pag. 12
2.3.5. Shut-down due to temperature probe malfunction pag. 12
2.4. Maintenance pag. 12
2.5. Notes for the user pag. 12
3. Technical characteristics and dimensions pag. 13
3.1. Dimensions pag. 14
3.2. Layout pag. 15
3.3. Operating data pag. 16
3.4. General characteristics pag. 16
4.Instructions for the fitter pag. 17
4.1. Reference standard pag. 17
4.2. System details pag. 18
4.2.1. Central heating circuit pag. 18
4.2.2. Filling the central heating system pag. 18
4.2.3. Domestic hot water circuit pag. 19
4.3. Site requirements pag. 19
4.3.1. Choosing where to install the boiler pag. 19
4.3.2. Positioning the boiler pag. 19
4.3.3. Boiler room ventilation pag. 21
4.3.4. Flue pag. 21
4.4. Installation (authorised personnel) pag. 22
4.4.1. Packaging pag. 22
4.4.2. Installing the boiler pag. 22
4.4.3. Gas main connection pag. 22
4.4.4. Hydraulic connections pag. 23
4.4.5. Adjustable by-pass pag. 25
4.5. Flue options pag. 25
4.5.1. Air intake/ue gas discharge system pag. 25
4.5.2. Conguration of air/ue system pipes pag. 26
4.5.3. Ø 100/60 mm air/ue gas coaxial duct system pag. 27
4.5.4. Ø 80 mm air/ue gas split duct system pag. 28
 4.5.5.Electricalsupplyconnection pag. 31
4.5.6. Room thermostat connection (optional equipment) pag. 31
 4.5.7.Externaltemperatureprobeinstallation(optionalequipment)and“slidingtemperature”operation pag. 31
 4.5.8.InstallationoftheOPENTHERMremotecontrol(optionalequipmentonlyforHRmodel) pag. 33
4.5.9. Loading the system pag. 33
4.6. Burner adjustment pag. 34
5.Commissioning pag. 35
5.1. Commissioning the boiler pag. 35
5.2. Setting the timer pag. 35
5.3. Checking pag. 35
5.4. Switching on and switching off pag. 35
6. Servicing pag. 36
6.1. General warnings pag. 36
6.2. Boiler inspection pag. 36
6.3. Servicing schedule pag. 36
6.4. Analysis of combustion parameters pag. 36
6.5. Testing combustion efciency pag. 37
6.5.1. “Chimney sweep” function pag. 37
6.5.2. Measurements pag. 37
 6.6. Wiringdiagram pag. 38
6.7 Hydraulic loss pag. 39
7. Spare part list pag. 40
8.Troubleshooting pag. 44
Benchmark Commissioning checklist pag. 46

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2. Instructions for the user
Fondital is a licensed member of the Benchmark Scheme which aims to improve the standards of installation and commissioning of
domestic heating and hot water systems in the UK and to encourage regular servicing to optimise safety, efciency and performance.
Benchmark is managed and promoted by the Heating and Hotwater Industry Council.
For more information visit www.centralheating.co.uk
Please ensure that the installer has fully completed the Benchmark Checklist on the inside back pages of the installation instructions
supplied with the product and that you have signed it to say that you have received a full and clear explanation of its operation. The
installer is legally required to complete a commissioning checklist as a means of complying with the appropriate Building Regulations
(EnglandandWales).
All installations must be notied to Local Area Building Control either directly or through a Competent Persons Scheme. A Building Regu-
lations Compliace Certicate will then be issued to the customer who should, on receipt, write the Notication Number on the Bench-
mark Checklist.
This product should be serviced regularly to optimise its safety, efciency and performance. The service engineer should complete the
relevant Service Record on the Benchmark Checklist after each service.
The Benchmark Checklist may be required in the event of any warranty work and as supporting documentation relating to home im-
provements in the optional documents section of the Home Information Pack.
2.1. Control panel
1. Power mains connection light (green)
This light indicates that the power supply to the boiler is on.
2. Indicator light (red)
Whenthislightison,itmeansthetemperatureofthewaterintheheatingsystemisbetween25°Cand35°C.
Whenthislightisashing,itmeanstheboilerhasshutdownduetoamalfunction.
3. Indicator light (red)
Whenthislightison,itmeansthetemperatureofthewaterintheheatingsystemisbetween36°Cand45°C.Whenthislightisashing,
it means the boiler’s safety thermostat has shut the boiler down.
4. Indicator light (red)
Whenthislightison,itmeansthetemperatureofthewaterintheheatingsystemisbetween46°Cand55°C.
Whenthislightisashing,itmeansthereisafaultintheairintakeand/oruedischargepiping.
5. Indicator light (red)
Whenthislightison,itmeansthetemperatureofthewaterintheheatingsystemisbetween56°Cand65°C.
Whenthislightisashing,itmeanstheburnerhasshutdown.
6. Indicator light (red)
Whenthislightison,itmeansthetemperatureofthewaterintheheatingsystemisbetween66°Cand75°C.
Whenthislightisashing,itmeansthewaterpressureintheboileristoolow.
7. Indicator light (red)
Whenthislightison,itmeansthetemperatureofthewaterintheheatingsystemisbetween76°Cand85°C.
Whenthislightisashing,itmeanstheCHtemperatureisabove85°C.
8. Indicator light (yellow)
Whenthislightison,itmeanstheameispresentontheburner.
Whenthislightisashing,itmeanstheboilerhasshutdownduetoamalfunction.
pic. 1
5 9 10 11 121 2 3 6 7 84

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12. Time clock
The time clock is for central heating control only. The clock is provided with a selector switch with three positions:
a) Position “I” CONSTANT: in this position, the clock circuit is always closed (switch on), therefore the boiler will constantly on and
 willonlyshutoffupontherequestoftheroomthermostat(ifinstalled)ortheheatingthermostat;
b) Position “O”HEATINGOFF:inthisposition,theclockcircuitisalwaysopen(switchoff)andtheboilerwillthereforenever 
 igniterforheating,Domestichotwaterwilloperateondemand;
c) “Central” positionPROGRAMMINGACTIVE:inthisposition,theprogrammingsetbytheuserisactive.
Using the three position switch the timer will allow either constant operation, timed operation or central heating off. Move the switch
bottom by sliding to the desired position.
The time clock is provided with 72 switches, each of which cover a time interval of 20 minutes (three per hour).
Whenariderisswitchedfromtheoutside(onsetting)totheinsideoftheclockborder(offsetting),
the circuit is open (switch off) for a period of 20 minutes and then the boiler stops.
For set the time of day, turn the timer outer bezel clockwise, to align the pointer with the correct
time to the nearest 20 minutes. Do not at any time attempt to turn the bezel anti-clockwise.
For set the timed heating program, decide which times of the day the central heating is required.
The heating will operate when the green tappets are set to the outer edge of the bezel.
To ensure the heating stays OFF set the required tappets inwards towards the centre of the bezel.
ON OFF
Tapped position
9. Boiler mode
WhentheknobisintheOFFpositiontheboilerisinstand-bymode.
WhentheknobisintheSUMMERposition ,theboilersuppliesDHWonly.
WhentheknobisintheWINTERposition ,theboilersuppliesbothCHandDHW.
WhentheknobisintheANTI-FREEZEposition , only the boiler anti-freeze function is active.
WhentheknobisturnedtotheRESETpositionandback , the boiler resumes operation.
10. DHW temperature regulator
ThisknobisusedtosettheDHWtemperaturewithintherange35-57°C
WARNING
Theboilerhasaspecialbuilt-inregulatorthatlimitsDHWowupto10litresperminute.InadditiontotheDHWtemperaturesetonthis
regulator,theDHWtemperaturealsodependsontheamountofwaterrequestedbytheuserandthesupplytemperature.
11. CH temperature adjustment
This knob is used to set the temperature of the water in the heating system. The setting range is 35 - 78°C.

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2.2. Operating the boiler
2.2.1. Switching on
These instructions presuppose that the boiler has been installed by an authorized fitter, started up for the first time and
set up for correct operation.
•Openthegasstopcock.
•Connecttheboilertothemainspowersupply(LIGHT 1 on the control panel comes on).
•Chooseboilermodebyoperatingthe“OFF/SUMMER/WINTER/ANTI-FREEZE”selector(9).
•TurntheCHtemperatureadjustmentknob(11) to set the temperature required for the heating system.
•TurntheDHWtemperatureknob(10)tosetthetemperaturerequiredfortheDHW(HC).
•Setdesiredroomtemperaturebymeansoftheroomthermostatinthepremises(whenavailable).
WARNING: If the boiler is not used for a long time, particularly if it runs on LPG, ignition may be difficult.
Before operating the boiler, switch on another gas-powered device (e.g. kitchen range or oven). Be aware that even if this
procedure is followed, the boiler may still experience some starting difficulties and shut down once or twice.
Reset the boiler by operating knob (9), then turn the knob back to the required position. Allow three minutes between each
attempt to re-light the boiler.
2.2.2. CH function
Use the regulation knob (11, pic. 1) to set the temperature in the central heating system.
The temperature setting range is 35-78°C (from the counter-clockwise limit position to the time limit position).
The CH temperature can be read from lights 2÷7 (pic. 1) on the control panel.
To prevent frequent ignition and switching off in heating mode, the boiler has a 4-minute waiting time between subsequent ignitions.
If the water temperature in the system fall below 40°C, waiting procedure is aborted and the boiler re-ignites (Antifast function).
COLOUR DISPLAY ACCORDING TO BOILER STATUS
Regular working LIGHT 1 LIGHT 2 LIGHT 3 LIGHT 4 LIGHT 5 LIGHT 6 LIGHT 7 LIGHT 8
Power connected to boiler GREEN n/a n/a n/a n/a n/a n/a n/a
Burner on GREEN n/a n/a n/a n/a n/a n/a YELLOW
CH temperature < 25°C GREEN OFF OFF OFF OFF OFF OFF n/a
26°C < CH temperature < 35°C GREEN RED OFF OFF OFF OFF OFF n/a
36°C < CH temperature < 45°C GREEN OFF RED OFF OFF OFF OFF n/a
46°C < CH temperature < 55°C GREEN OFF OFF RED OFF OFF OFF n/a
56°C < CH temperature < 65°C GREEN OFF OFF OFF RED OFF OFF n/a
66°C < CH temperature < 75°C GREEN OFF OFF OFF OFF RED OFF n/a
76°C < CH temperature < 85°C GREEN OFF OFF OFF OFF OFF RED n/a
Table 1 - Colour displayed by Light in relation to boiler operation status
Malfunctions LIGHT 1 LIGHT 2 LIGHT 3 LIGHT 4 LIGHT 5 LIGHT 6 LIGHT 7 LIGHT 8
Power is missing OFF OFF OFF OFF OFF OFF OFF OFF
Safety thermostat shutdown GREEN OFF RED L OFF OFF OFF OFF OFF
Air/flue gas pressure switch
shutdown
GREEN OFF OFF RED L OFF OFF OFF OFF
Shutdown due to flame absence GREEN OFF OFF OFF RED L OFF OFF OFF
Water pressure switch shutdown GREEN OFF OFF OFF OFF RED L OFF OFF
Gas valve alarm GREEN OFF RED L OFF OFF OFF OFF YELLOW L
Water temperature switch alarm (>85°C) GREEN OFF OFF OFF OFF OFF RED L OFF
DHW flow probe alarm GREEN RED L OFF OFF OFF OFF OFF OFF
CH flow probe alarm GREEN RED L OFF OFF OFF OFF OFF YELLOW L
External cylinder probe alarm GREEN RED LA OFF OFF OFF OFF OFF YELLOW LA
Remote control malfunction GREEN OFF OFF RED L OFF OFF OFF YELLOW L
Table 2- Colour displayed by Light in relation to boiler malfunction status
KEY TO ACRONY
OFF LIGHT off
RED    LIGHTon,displayingthecolourshownonthetable
LRED    LIGHTorlightsashing,displayingthecolourshownonthetable
LARED    LIGHTSashing,displayinginsequencethecoloursshownonthetable
n/a LIGHT status not relevant

10
2.2.3. DHW function
The domestic hot water supply function is active on model HC, and on model HR with an (optional) external water heater. This function
always has priority over central heating water.
For model HC, the temperature setting range is 35-57°C (from the counter-clockwise limit position to the time limit of regulation knob 10).
FormodelHRwithan(optional)externalwaterheaterwithanNTCprobe(10kΩ@ß=3435;refertothewaterheaterspecications),the
temperature setting range is 35-57°C (from the counter-clockwise limit position to the time limit of regulation knob 10).
FormodelHRwithan(optional)externalwaterheaterwiththermostatprobe,thedesiredDHWtemperaturemustbesetonthewater
heater (refer to the attached instructions). Regulation knob 10 has no effect on this conguration.
Theboileristtedwithaow-limitingdevicethatallowsamaximumDHWowof10litresperminute.
TheDHWowratedependsontheboiler’sthermalcapacityandthemainswatersupplytemperature,andcanbecalculatedfromthe
following formula:
K
l=DHWliterperminute=--------
∆ T
K represents:
349 (HC 24)
434 (HC 32)
ΔT=DHWtemperature–mainswatersupplytemperature.
E.g.InmodelHC24,ifthemainswatersupplytemperatureis8°CandDHWisrequiredat38°C,thevalueofΔTis:
ΔT=38°C–8°C=30°C
andDHWlitres(lperminute)availableattherequiredtemperatureof38°Cis
I = 349 / 30 = 11.7 [litres per minute - mixed water to the tap].
2.2.4. ANTI-FREEZE FUNCTION
Thisboileristtedwithananti-freezeprotectionsystem,whichworkswhenthefollowingfunctionsareactivated:SUMMER,WINTER
andANTI-FREEZE.
The anti-freeze function only protects the boiler, not the whole heating system. The heating system must be protected
using a room thermostat, although this is disabled when the selector is set to the ANTI-FREEZE or OFF mode.
Therefore, if you want to protect both the boiler and the system, turn to WINTER mode on selector 9.
Whentheheatingwatertemperaturesensordetectsawatertemperatureof5°C,theboilerswitchesonandstaysonatitsminimum
thermal power until the temperature reaches 30°C or 15 minutes have elapsed. The pump continues to operate even if the boiler shuts
down.
InmodelHC,anti-freezefunctionalsoprotectstheDHWcircuit.
WhentheDHWtemperaturesensordetectsatemperatureof5°C,theboilerswitchesonandstaysonatitsminimumthermalpower
untilthetemperaturereaches10°Cor15minuteshaveelapsed(thedeviatingvalveisintheDHWposition).Thepumpcontinuesto
operate even if the boiler shuts down.
In boilers with an external heater for the supply of domestic hot water, which have a thermostat-type temperature sensor, the anti-freeze
function does NOT protect the water heater. It can be protected by setting the boiler to Summer orWinter , or by setting a
value above 0°C on the water heater thermostat.
In CH boilers with an external water heater for the supply of domestic hot water, which have an NTC temperature sensor (10 kΩ @
ß=3435;refertotheboilerspecications),theanti-freezefunctionprotectsthewaterheateraswell.
Whentheexternalcylindertemperaturesensordetectsawatertemperatureof5°C,theboilerswitchesonandstaysonatitsminimum
thermal power until the temperature of the water in the external cylinder reaches 10°C or 15 minutes have elapsed. The pump continues
to operate even if the boiler shuts down.
The CH system can be protected effectively against freezing by means of specic anti-freeze additives suitable for use in multi-metal
systems.
Do not use car engine anti-freeze products, and periodically check the effectiveness of the anti-freeze product.
2.2.5. PUMP AND THREE-WAY VALVE ANTI-SEIZE FUNCTION
Wheretheboileristoremaininactiveand:
- no. 9selectorisnotsettotheOFFposition;
- boilerisnotdisconnectedfromelectricmainpowersupply;
the circulation pump (for all models) and three-way valve (HC model), are operated for 30 second every 24 hours in order to prevent the
components from seizing.
2.2.6. External probe operation (optional equipment)
The boiler can be equipped with an (optional) external temperature probe, by means of which the boiler adjusts the CH water
temperature according to the outdoor temperature, in other words, increasing the CH water temperature when the outdoor temperature
decreases, and vice-versa. This increases energy-saving operation (this boiler mode is called “sliding temperature operation”).

11
The boiler microprocessor program determines CH water temperature variations.
Whenanexternaltemperatureprobeisconnectedtotheboiler,theCHwatertemperatureadjustingknob(11, pic. 1) loses its function
and becomes a room temperature control device.
Whenknob11isturnedfullycounter-clockwise,theroomtemperaturesettingis15°C;whensetto9o’clock,thetemperatureis18°C;
whensetto12o’clock,thetemperatureis25°C;whensetto3o’clockthetemperatureis32°C;whenitisturnedfullyclockwisethe
temperature is 35°C.
For the best curve setting, it is advisable to set the temperature at around 20°C.
Picture 2 shows the curves for a room temperature of 20°C. As this value is increased via the regulation knob 11, the curves move
upwards.Withthissetting,ifforexampleyouselectthecurvecorrespondingtocoefcient1,withanoutdoortemperatureof-4°C,the
ow temperature will be 50°C.
Refer to subsection 4.5.7 for detailed sliding temperature operation.
2.3. Boiler lockout
If a malfunction occurs, the boiler automatically shuts down.
Refer to tables 1 and 2 for boiler status.
In order to determine the probable causes of the malfunction, refer to section 8 - Troubleshooting - at the end of this manual (in addition
to tables 1 and 2).
Follow the procedure described for the type of shut-down.
2.3.1. Burner lockout
Whentheburnershutsdownbecausetheamehasgoneout,light5(red)startsashing.Ifthishappens,proceedasfollows.
•Checkthatthegasstopcockisopen,andmakesurethegasmainisactuallyprovidingservicebylightingagas-poweredkitchen
appliance such as a kitchen range or oven.
•Oncethepresenceofgashasbeenveried,resettheburnerbyturningknob9totheRESETpositionfor2seconds,andthen
to the desired operating mode. If the boiler does not shut down, and you have performed the reset procedures three times, contact an
authorized Service Centre or a qualied service engineer.
Should frequent burner shut-down occur, a recurrent malfunction may be present. Contact an authorized Service Centre or a qualied
service engineer.
2.3.2. Shut-down due to overheating
WhentheCHwatergetstoohot,theboilershutsdown,andlight3(red)startsashing.Ifthishappens,contactanauthorizedService
Centre or a qualied service engineer.
Should the above happen contact the Fondital helpline UK or CORGI registered engineer with appropriate competence for service.
2.3.3. Shut-down due to inadequate air/flue gas draught
If the burner shuts down due to a malfunction of the air intake and/or ue discharge piping, light 4 starts to ash.
Should the above happen contact the Fondital helpline UK or CORGI registered engineer with appropriate competence for service.
External temperature (°C)
CH flow temperature (°C)
Thermoregulation curves
coefficient
100
80
60
40
20
20 16 12 840-4 -8 -12 -16
1
1,25
1,5
2
2,5
3
pic. 2

12
2.3.4. Shut-down due to low water pressure
If red shout-down light 6comes on, it indicates low water pressure and intervention of the low water pressure switch.
The following situation may occur: the water pressure gauge (pic.3) indicates a pressure value lower than 1 bar.
Follow the loading procedure as below described:
- opentheloadingtapupstreamtheboilertollthesystemwithwater;
- keeptheloadingtapopenuntilthewaterpressuregaugereads1÷1.3bar;
- closetheloadingtap;
- reset the burner by turning knob 9totheRESETpositionfor2seconds,andthentothedesiredoperatingmode.
Should the boiler shut down again, contact the Fondital helpline UK or CORGI registered engineer with appropriate competence for
service.
Once the loading procedure is completed, properly close the loading tap. Should the tap not be appropriately closed,
as pressure increases, CH system safety valve may open and water flow out.
2.3.5. Shut-down due to temperature probe malfunction
If the burner shuts down due to temperature probe malfunction, the following lights start to ash:
•Redlightno.2andyellowlightno.8whenCHprobemalfunctionoccurs.
•Redlightno.2whenDHWprobemalfunctionoccurs.
•Redlightno.2andyellowlightno.8(ashingalternately)forexternalcylinderprobe(modelHRwithexternalboilerandNTC
temperature probe).
Should the boiler not re-start and still remain in the above status, contact the Fondital helpline UK or CORGI registered engineer with
appropriate competence for service.
2.4. Maintenance
Routine boiler maintenance must be provided according to the applicable laws in the country of installation and following the instructions
given in the relevant section in this manual. Correct maintenance ensures that the boiler operates efciently, is environmentally friendly,
and is not a danger to people, animals or property.
By law, only qualied personnel are allowed to service the boiler.
The Manufacturer recommends that Customers contact an authorized Service Centre for maintenance and repairs.
Formaintenanceinterventions,refertosection6–Maintenance.
The external boiler housing must only be cleaned with standard household cleaning products.
Do not use water!
2.5. Notes for the user
The user may only access boiler parts that can be reached without using any technical equipment or tools. The user is not au-
thorized to remove the boiler housing or touch any of the internal parts.
No one, including qualified service engineers, is authorized to modify the boiler.
The manufacturer can not be held liable for damage to people, animals, or property due to tampering or improper work done to the
boiler.
If the boiler remains inactive and the power supply disconnected for a long time, the pump may not operate.
Pump servicing includes removing the boiler housing and accessing the internal parts of the boiler, so this must only be done by
a qualified service engineer.
Pump blockage can be avoided by adding to the water lming additives suitable for multi-metal systems.
Water pressure gauge
pic. 3

13
3. Technical characteristics and dimensions
The boiler is equipped with an atmospheric burner. All versions are equipped with electronic ignition and ionization ame control.
The following models of boiler are available:
- HC24:sealedchamberandforceddraught,electronicignitionandinstantDHWsupply(25.5kW);
- HR24:sealedchamberandforceddraught,electronicignition,CHsupplyonly(25.5kW);
- HC32:sealedchamberandforceddraught,electronicignitionandinstantDHWsupply(31.5kW);
- HR32:sealedchamberandforceddraught,electronicignition,CHsupplyonly(31.5kW);
The boilers meet local applicable Directives enforced in the country of destination, which is stated on their data plate.
Boiler installation in a different country from specied may endanger people, animals and objects.
The main technical characteristics of the boilers are listed below:
Construction characteristics
- IPX4D electrically protected control panel
- Integrated, modulating electronic safety board
- Electronicignitionviaseparatedtransformerand
ionization ame detection
- Stainless steel multi-gas atmospheric burner
- Modulating gas valve with double shutter
- Mono-thermal, high efciency, composite and stainless
steel heat exchanger with air purging device
- StainlesssteelDHWheatexchanger(onlyHC)
- Motorized deviating valve (only HC)
- Three-speed pump with air purging device
- Safety ow-switch, preventing operation with low water
pressure in the CH system
- 8 litre expansion vessel
- DHWpriorityowswitch(onlyHC)
- 10litres/minDHWowlimitingdevice(onlyHC)
- Integrated, automatic by-pass
- Boiler lling and draining taps
- CH(allmodels)andDHW(onlyHC)temperatureprobes
- Safety limit thermostat
- Flue pressure switch
User interface
- RESET,STAND-BY,SUMMER/WINTER,SUMMERand
 ANTI-FREEZEfunctionselector
- DHWtemperatureswitchformodelHCandHRequippedwith
external cylinder and NTC temperature probe (35-75 °C)
- Leds indicating water temperature
- Waterpressuregauge
- CH temperature switch (35-78 °C)
Operating characteristics
- CH mode electronic ame modulation, timer controlled ame
rising ramp (50 seconds)
- DHWmodeelectronicamemodulation,timercontrolledame
rising ramp (for models HC and HR equipped with external
cylinder and NTC temperature probe)
- DHWpriorityfunction
- CHowanti-freezefunction:ONat5°C;OFFat30°Corafter
15 minutes operation when CH water > 5 °C
- DHWanti-freezefunction:ONat5°C;OFFat10°Corafter
 15minutesoperationwhenDHWtemperature>5°C;(for
models HC and HR equipped with external cylinder and NTC
temperature probe)
- Externalboileranti-freezefunction(HR+externalcylinder
 equippedwithNTCprobe):ONat5°C;OFFat10°Corafter
15 minutes operation when external cylinder water
temperature > 5 °C
- Timer controlled “chimney sweep” function: 15 minutes
- “Anti-Legionnaires’ disease function (only for model HR
equipped with external cylinder and NTC temperature probe)
- Flame propagation function during ignition
- CH max heat output adjusting trimmer
- Ignition heat output adjusting trimmer
- Timer-controlled room thermostat (240 seconds when CH ow
temperature >40°C)
- Pump over run function in CH, anti-freeze or chimney sweep
mode (180 seconds)
- PumpoverrunfunctioninDHW(30seconds)
- CH temperature post-circulation function: >85°C:30 seconds
- Safetypost-circulationfunction(ON:95°C;OFF:90°C)
- Pump and deviating valve anti-locking function (180 seconds
operation after 24 hours of boiler inactivity)
- Can be connected to a room thermostat (optional)
- Can be connected to an external temperature probe (optional
supplied by the Manufacturer)
- Can be connected to a cylinder timer connection (only for
model HR equipped with external cylinder and NTC
temperature probe).

14
3.1. Dimensions
750
450
175
140 225
325
138
177
809875985643
SI
S
G
F
DHW CWI
SV
R
RS
S Condensate drain
F CH system ow
G Gas intake
SI Inspection trap plug
 DHW DHWhotwaterdrawoff(HCmodelonly)
CWI Coldwaterinlet(HCmodelonly)
SV 3-bar safety valve drain cock
R CH system return
RS Drain cock
pic. 4
Bottom view Top view

15
3.2. Layout
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
20
21
22
23
24
25
1. Condensate drain
2. Modulating gas valve
3. CH temperatura probe
4. Burner nozzles
5. Flame detection electrode
6. Safety thermostat
7. Heat exchanger
8. Sealed combustion chamber
9. Flue gas extraction fan
10. Flue gas pressure test point
11. Flue gas pressure safety switch
12. Flue gas pressure micro switch
13. Condensate detection probe
14. Safety thermostat
15. Air intake/ue gas pipe
16. Flue gas recoverer
17. Flue gas pressure test point
 18. Expansionvesselllingtap
 19. Expansionvessel
20. Ignition electrode
21. Air purging device
22. Pump
 23. Waterpressureswitch
24. 3-bar safety valve
25. Unloading tap
1. Condensate drain
 2. DHWtemperatureprobe
3. Modulating gas valve
4. CH temperature probe
5. Burner nozzles
6. Burner
7. Flame detection electrode
8. Safety thermostat
9. Heat exchanger
10. Sealed combustion chamber
11. Flue gas extraction fan
12. Flue gas pressure test point
13. Flue gas pressure safety switch
14. Flue gas pressure micro switch
15. Condensate detection probe
16. Flue gas recoverer
17. Safety thermostat
18. Air intake/ue gas intake
19. Flue gas pressure test point
 20. Expansionvesselllingtap
 21. Expansionvessel
22. Ignition electrode
23. Air purging device
24. Pump
 25. Waterpressureswitch
26. Safety valve
 27. DHWowlimitingdevice(max10litre/minute)
28. Flow switch
29. Mains water inlet lter
30. Adjustable by-pass
31. Three way valve
32. Secondary plate heat exchanger
G
30
31
2
1
3
4
5
6
7
8
9
10
11
12
13
15
16
17
18
19
20
21
22
22
23
24
25
26
27
28
29
32
14
S
pic. 5
HR MODEL
pic. 6
HC MODEL

16
3.3. Operating data
Burner pressures must be veried after a three minute boiler operation time.
HC 24 / HR 24
Function
Heat
input
[kW]
Heat
output
80-60°C
[kW]
Heat
output
50-30°C
[kW]
Mains gas
pressure
[mbar]
Nozzle diam-
eter
[mm]
Burner pressure
[mbar]
min max min max min max min max
Methane gas G20 11.5 25.5 10.7 24.4 11.4 26.4 20 1.25 2.90 13.2
Butane gas G30 11.5 25.5 10.7 24.4 11.4 26.4 28-30 0.77 5.74 27.7
Propane gas G31 11.5 25.5 10.7 24.4 11.4 26.4 37 0,77 6,5 29,5
Table 3 - Calibration data for HC 24 and HR 24
3.4. General characteristics
HC 24 HR 24 HC 32 HR 32
Category - II2H3+ II2H3+ II2H3+ II2H3+
Burner nozzles no. 12 12 15 15
Minimum CH ow rate l/h 500 500 500 500
Minimum CH pressure bar 0.5 0.5 0.5 0.5
Maximum CH pressure bar 3 3 3 3
MinimumDHWpressure bar 0.5 - 0.5 -
MaximumDHWpressure bar 8 - 8 -
DHWspeciccapacity( ∆t 30°C) l/min 11.8 - 15.0 -
Electricalpowersupply-voltage/frequency V ~ Hz 230 ~ 50 230 ~ 50 230 ~ 50 230 ~ 50
Power mains supply fuse A 2 2 2 2
Maximum power consumption W142 142 177 177
Net weight kg 43.3 41.0 44.5 41.9
Natural gas consumption(*) m3/h 2.698 2.698 3.333 3.333
Butane gas consumption Kg/h 2.008 2.008 2.480 2.480
Propane gas consumption Kg/h 1.977 1.977 2.442 2.442
Maximum CH working temperature °C 78+5 78+5 78+5 78+5
MaximumDHWworkingtemperature °C 57+5 57+5 57+5 57+5
Total capacity of expansion vessel l 8 8 8 8
Maximum recommended CH system capacity l 100 100 100 100
Table 5 - General data for each model
(*) Value referred to 15 °C - 1013 mbar
Hot water supply ∆T 45°C = 7.8 l/min
Hot water supply ∆T 40°C = 8.7 l/min
Hot water supply ∆T 35°C = 10.0 l/min
Hot water supply ∆T 30°C = 11.7 l/min *
Hot water supply ∆T 25°C = 14.0 l/min *
*Note: mixed water to the tap
HC 32 / HR 32
Function
Heat
input
[kW]
Heat
output
80-60°C
[kW]
Heat
output
50-30°C
[kW]
Mains gas
pressure
[mbar]
Nozzle diam-
eter
[mm]
Burner pressure
[mbar]
min max min max min max min max
Methane gas G20 12.0 31.5 11.2 30.3 12.0 32.7 20 1.25 2.90 13.2
Butane gas G30 12.0 31.5 11.2 30.3 12.0 32.7 28-30 0.76 4.7 29.0
Propane gas G31 12.0 31.5 11.2 30.3 12.0 32.7 37 0,76 6,5 29,5
Table 4 - Calibration data for HC 32 and HR 32
Hot water supply ∆T 45°C = 9.6 l/min
Hot water supply ∆T 40°C = 10.9 l/min
Hot water supply ∆T 35°C = 12.4 l/min
Hot water supply ∆T 30°C = 14.5 l/min *
Hot water supply ∆T 25°C = 17.4 l/min *
*Note: mixed water to the tap

17
HC 24 / HR 24 Max. heat output Min. heat output 30% heat output
Boiler casing heat loss with burner on % 1.71 2.06 -
Flue system heat loss with burner on % 2.39 4.74 -
Flue system mass capacity g/s 13.5 14.3 -
Fluetemp.–airtemp. °C 47.9 45.4 -
CO2(gas G20) % 7.5 3.0 -
CO2(gas G30) % 9.1 3.6 -
Boiler efciency rate (80-60 °C) (Net) % 95.8 93.2 -
Boiler efciency rate (50-30 °C) (Net) % 103.4 99.4 -
Boiler efciency at 30 % of the load (Net) % - - 100.9
Efciencyrating(accordingto92/42/CE) -
SEDBUKclassicationHC24kW - B (86.5 %)
SEDBUKclassicationHR24kW - B (86.6 %)
NOx emission class - 3
Table 6 - HC 24 - HR 24 model combustion rates
HC 32 / HR 32 Max. heat output Min. heat output 30% heat output
Boiler casing heat loss with burner on % 1.31 0.66 -
Flue system heat loss with burner on % 2.59 5.94 -
Flue system mass capacity g/s 16.7 16.7 -
Fluetemp.–airtemp. °C 54.9 50.6 -
CO2(gas G20) % 7.6 2.6 -
CO2(gas G30) % 9.0 3.0 -
Boiler efciency rate (80-60 °C) (Net) % 96.1 93.4 -
Boiler efciency rate (50-30 °C) (Net) % 103.8 99.8 -
Boiler efciency at 30 % of the load (Net) % - - 100.0
Efciencyrating(accordingto92/42/CE) -
SEDBUKclassicationHC32kW - B (86.2 %)
SEDBUKclassicationHR32kW - B (86.3 %)
NOx emission class - 3
Table 7 - HC 32 - HR 32 model combustion rates
4. Instructions for the fitter
ThisisanII2H3+categoryboilerandmustbeinstalledincompliancewithlawsandstandardsenforcedinthecountryofinstallation,
which are here considered as entirely transcribed.
4.1. Reference standard
In GB, the installation must be carried out by a CORGI Registered Installer. To check for authorised qualied engineers please contact
CORGI 01256-372400. It must be carried out in accordance with the relevant requirements of the:
- GasSafetyRegulations;
- The appropriate Building Regulations either The Building Regulation, The Building Regulations (Scotland), Building Regulations
 (NorthernIreland);
- TheWaterFittingsRegulationsorWaterBylawsinScotland;
- ThecurrentI.E.E.WiringRegulations.
Wherenospecicinstructionsaregiven,referenceshouldbemadetotherelevantBritishStandardsCodeofPractice.
The following list is the full lists of codes of practice and British Standards that engineers should work to in the UK.
It is law in the UK that a competent person installs all gas-burning appliances. Please ensure that the installer is a class of person ap-
provedforthetimebeingbytheHeathandSafetyExecutiveforthepurposeofcarryingoutthiswork.Anapprovedengineershouldbe
registered to an approved scheme i.e. CORGI 01256-372400.
In GB, the following Codes of Practice apply:
BS 5440: Part 1 2000 - Flues
BS 5440: Part 2 2000 - Air Supply
BS 5446: Installation of hot water supplies for domestic purposes (1st, 2nd and 3rd family gases)
BS 5449: 1990 Forced circulation hot water systems
BS 6700: 1987 - Installation of cold water supplies for domestic purposes (1st, 2nd and 3rd family gases)
BS6798:2000Specicationforinstallationofgas-redboilersofratedinputnotexceeding70kWnet
BS6891:Specicationforinstallationoflowpressuregaspipeworkofupto28mm(R!)indomesticpremises(2ndfamilygas)
BS7074:ExpansionVesselsandancillaryequipmentforsealedwatersystems
BS 7593: 1992 Code of practice for treatment of water in domestic hot water central heating systems
BS7671:2001IEEwiringregulations.

18
This appliance meets the requirements of:
- UNIEN677forGAS-FIREDCENTRALHEATINGBOILERS.SPECIFICREQUIREMENTSFORCONDENSINGBOILERSWITH
 NOMINALHEATINPUT≤70kW,
- IPX4D rating for electrical appliances,
- EMCDIRECTIVE89/336CE,
- LVDDIRECTIVE2006/95CE,
- BOILEREFFICIENCYDIRECTIVE92/42CE
Failure to install a gas appliance correctly and in accordance with the above norms could lead to prosecution. It is in the interest of the
installer and safety that the law is complied with.
The manufacturers instructions form an integral part of the installation and should be left with the appliance but do not over ride in any-
way statutory obligations.
4.2. System details
4.2.1. Central heating circuit
The boiler is designed for use in a sealed central heating system in accordance with the requirements of BS 5449 and BS 6798. The
systemshouldbedesignedtooperatewithowtemperaturesofupto78°C.Whendesigningthesystem,thepumphead,expansion
vessel size, mean radiator temperature, ect. must all be taken into account. Refer to the pump performance table for guidelines.
System volume: the expansion vessel incorporated into the boiler is suitable for a sealed heating system. The boiler is supplied with the
following components built in:
Pressure relief valve: set to operate at 3 bars. The outlet connection of the boiler safety valve must terminate to atmosphere in accord-
ance with current regulations. The manufacturer will not be held responsible for ooding caused by the operation of the safety valve in
the case of system overpressure.
Pressure gauge: to indicates the system pressure to be maintained.
Expansion vessel: capacity of 8 litres.
By-pass: The boiler incorporates an automatic by-pass.
All recirculatory water systems will be subject to corrosion unless an appropriate water treatment is applied. This means that the ef-
ciency of the system will deteriorate as corrosion sludge accumulates within the system, risking damage to pump and valves, boiler
noise and circulation problems.
All systems must be thoroughly drained and ushed out. System additives - corrosion inhibitors and ushing agents/descalers should
comply to BS7593 requirements. It is important to check the inhibitor concentration after installation, system modication and at every
service in accordance with the manufacturer’s instructions.
4.2.2. Filling the central heating system
The system design pressure (cold) should be set to 1,5 bar. This pressure is equivalent to a static head of 15,4 metres of water. Provision
should be made to replace water lost from the system. This can be by manual or automatic means as shown in Pics. 7 and 8. A double
check valve assembly must be used as show in pic 8.
FillingofthesystemmustbecarriedoutinamannerapprovedbythelocalWaterUndertaking.Whereallowedthesystemmaybelled
via a temporary connection as shown in pic 7. After lling, always disconnect the exible hose of the lling loop. All ttings used in the
system must be able to withstand pressures up to 3 bar. Drain taps must be used to allow the system to be completely drained.
In order to prevent scaling or deposits in the primary heat exchanger, the mains supply water to the
heating circuit must be treated according to the requirements of standard.
This treatment is indispensable in the case where the circuit is frequently topped-up or when the system is
often either partially or fully drained.
Mains water
supply
Additional
stop valve
Hose unions
CH return
Temporary hose
(disconnect after filling) Double check valve
assembly
(note direction of flow)
Mains
water
supply
Overflow
Stop
valve
Test
cock
Double
check valve
assembly
Heating
circuit
return
Feed cistern to be
located above
highest point in
the system
pic. 7 pic. 8

19
4.2.3. Domestic Hot Water Circuit
AllDHWcircuits,connections,ttings,etc.shouldbefullyinaccordancewithrelevantstandardsandwatersupplyregulations.
YourattentionisdrawnforGB:GuidanceG17toG24andrecommendationR17toR24oftheWaterRegulationsGuide.
4.3. Site requirements
4.3.1. Choosing where to install the boiler
The following must be taken into account when choosing where to install the boiler:
- ApproveddocumentL1+L2governmentguidelines.
- Check the wall is strong enough to support the weight of the boiler.
- Do not t the boiler above any equipment that may affect operation (kitchen appliances that emit steam or greasy vapour, washing
machines, etc.).
- Do not install natural draught boilers in corrosive or very dusty atmosphere areas, such as hairdressing salons or laundries as this
would greatly reduce the boiler’s lifespan.
4.3.2. Positioning the boiler
Eachboilerissuppliedwithapapertemplate(pic.10),withinitspackaging,
allowingarrangementofCHpipesystem,DHWpipesystem,gassupplypipe
system and air intake/ue gas discharge system before actually installing the
boiler.
The template is made of heavy-duty paper, it is to be afxed to the wall where
the boiler is to be mounted using a carpenter’s level.
It provides all the indications required to drill the boiler xing holes to the wall,
procedure which is done using two screws and wall plugs.
The lower area of the template displays where to mark the exact point at which
the couplings are to be positioned for boiler connection to the gas supply pipe,
watermainssupplypipe,DHWowpipe,CHowandreturnpipes.
The upper area of the template displays where air intake and ue gas ducts are
to be positioned.
The manufacturer recommends leaving a space all round the boiler during
installation as follows:
- atleast2,5cmontherightandleft;
- at least 25 cm above and below.
This facilitates service operations on the boiler, e.g. maintenance and repair
interventions (pic. 9).
2,5 cm
Since the temperature of the walls on which the boiler is mounted and external temperature of coaxial air/flue gas
system do not exceed 60 °C, no minimum distance from flammable walls is to be accounted for.
Boilers with split pipe flue system: in presence of flammable walls and flue gas ducts through such walls, ensure air gap
of 15 mm between wall and flue gas ducts.
2,5 cm
25 cm
25 cm
pic. 9
2,5 cm

20
Domestic hot water
Cold water inlet
CH system return
Gas
Condensate drain
DHW
CWI
R
F
G
S
G
F
DHW
CWI
R
S
pic. 10