Unical DUA plus BTN 28 Installation And User Instruction Manual

Download

DUA plus

BTN 28 - BTFS 28

00333957 - 1st edition - 09/2011

INSTALLATION AND USER INSTRUCTION MANUAL

General info

While thanking you for buying an UNICAL product we invite you to carefully read the following forewarnings:

IMPORTANT

This INSTRUCTION MANUAL, which is an integral and indispensable part of the product, must be handed over to the user by the plumber. Read carefully the forewarnings contained in this manual because they supply important indications concerning the safetywhen using and maintaining the boiler. Kept the manual in a safe place for any future reference. The boiler must be installed by qualified personnel, in compliance with all applicable laws and standards, according to the manufacturer’s instructions given in this manual. Incorrect installation may cause injury to persons and/or animals and damage to property. The manufacturer shall not be held liable for any such injury and/or damage.

After removal of the packaging, which has to be sent to specific waste management sites for recycling, check that the boiler is intact and that it has not been damaged during transport and handling. Keep the packaging out of the reach of children as it may represent a choking and suffocation hazard. Do not install equipment which is patently damaged and/or faulty.

Before installing the boiler, check that the technical data supplied by Unical, correspond to requirements for its correct use in the system.

Before making any service on to the boiler switch off the power supply. 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 requirement may jeopardize the safety of the boiler and expose people, animals and proper ty to danger.

To grant the efficiency of the appliance and for its proper operation it is necessary to do a periodical service according to the

UNICAL's indications and local laws in force.

The manual must be handed over with the boiler should it be sold or transferred, in order that the new owner and/or installer can consult it.

Only original accessories must be used for all boilers supplied with optional kits (including electrical ones).

This boiler must be used for the purposes for which it has been designed. Any other use shall be considered incorrect and therefore dangerous.

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 UNICAL from any and all contractual and extracontractual liability.

To guarantee efficiency and correct functioning of the equipment it is legally binding to service the boiler once a year according to the schedule indicated in the relative section of this manual.

In the event of long periods of inactivity of the boiler, disconnect it from the power mains and close the gas tap (Warning! In this case the boiler’s 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 specific antifreeze products suitable for multi-metal heating systems.

N.B.: IF YOU SMELL GAS:

- do not turn on or off electrical switches and do not turn on electrical appliances;

- do not ignite flames and do not smoke;

- close the main gas tap;

- open doors and windows;

- contact a Service Centre, qualified installer or the gas supply company. Never use flames to detect gas leaks. WARNING This boiler has been built for installation in the country indicated on the technical data plate, which shows, in addition to the technical features, also the gas type for which it is prepared to work. In case these indications do not correspond to your requirements, please contact your nearest Unical supplier. Thanks for that.

"WATER TREATMENT IN C.H. SYSTEM FOR CIVIL USE" NOTE FOR INSTALLER AND USER

1) The frequency of the cleaning of the D.H.W. heat exchanger is related to the hardness of the feeding water.

2) With a water hardness higher than 14°f the use of antiscaling devices, whose choice will be made on the base of water characteristics, is suggested.

3) To increase the resistance to the scaling, a D.H.W. temperature adjustment very close to that one of the actual use, is suggested.

4) The adoption of a modulating room thermostat reduces the scaling danger.

5) We advise you to verify the state of cleaness of the D.H.W. heat exchanger at the end of the first year and subsequently every two years. PED Declaration

The appliance DUA plus BTN 28 e DUA plus BTFS 28

is not under the scope of the PED Directive 97/23/CE, because it belongs to a category lower than the 1st, on the base of the comparation of their features with the limits shown on the table 4 of the directive. Furthermore the appliance is already covered by the Directives 90/396/ CE (GAD - Gas Appliances Directive) and 73/23/CEE (LVD - Low Tension Directive)

General info

DATA PLATE DESCRIPTION

LEGEND:

1 = CE Surveillance notify body 2=Boiler type 3=Boiler model 4=Number of stars (Directive 92/42/CEE) 5=(S.N°) Serial number 6=P.I.N. code 7=Approved fluing configurations 8=(N0x) N0x class

A Central Heating circuit features

9=(Pn) Nominal output 10 = (Pcond) Condensing nominal output 11 = (Qmax) Nominal heat input 12 = (Adjusted Qn) Adjusted for nominal Heat input 13 = (PMS) Max. pressure C.H. system 14 = (T max) Max. C.H. temperature

B Domestic Hot Water circuit features

15 = (Qnw) Nominal heat input in D.H.W. mode (if different from Qn) 16 = (D) Specific D.H.W. flow rate according to EN 625-EN 13203-1

17 = (R factor) N° taps based on the quantity of water declared EN

13203-1

18 = (F factor) N°stars based on the quality of water declared

EN 13203-1 19 = (PMW) Max. pressure D.H.W. system 20 = (T max) Max. temperature D.H.W system

C Electrical features

21 = Electrical power supply 22 = Consumption 23 = Protection grade

D Countries of destination

24 = Direct and indirect country of destination 25 = Gas family 26 = Supply pressure

E Factory setting

27 = Adjusted for gas type X 28 = Space for national brands

CE Marking

- The CE marking documents that the boilers satisfy:

- The essential requirements of the Directive regarding gas appliances (Directive 90/396/CEE)

- The essential requirements of the Directive regarding electromagnetic compatibility (Directive 89/336/CEE)

- The essential requirements of the Efficiency Directive (Directive 92/42/CEE)

- The essential requirements of the low voltage Directive (Directive 73/23/CEE)

7 8

21 22

C D

General info

TECHNICAL CHARACTERISTICS AND

DIMENSIONS....................................................................... pag. 5

1.1 Technical characteristics ...................................................... pag. 5

1.2 Dimensions ............................................................................. pag. 5

1.3 Hydraulic circuits ................................................................... pag. 6

1.4 Operational data ..................................................................... pag. 8

1.5 General specifications ........................................................... pag. 8

INSTRUCTIONS FOR

THE INSTALLER .............................................................. pag. 9

2.1 Installations conditions .......................................................... pag. 9

2.2 Installation ............................................................................... pag. 9

2.2.1 Packaging .................................................................. pag. 9

2.2.2 Position of the boiler .................................................. pag. 10

2.2.3 Assembly the boiler ................................................... pag. 10

2.2.4 Ventilation ................................................................... pag. 11

2.2.5 Smoke evacuation systems ..................................... pag. 11

2.2.6 Smoke discharge system forced draught boilers ... pag. 14

2.2.7 Smoke discharge system forced draught boilers ... pag. 15

2.2.8 Smoke discharge with separate ducs Ø80 mm ...... pag. 16

2.2.9 On site combustion efficiency measurement .......... pag. 18

2.2.10 Gas supply line ......................................................... pag. 18

2.2.11 Hydraulic connections .............................................. pag. 18

2.2.12 Electrical connections ............................................... pag. 19

2.3 Electrical wirings .................................................................... pag. 20

2.3.1 Actual connection diagram ....................................... pag. 20

2.3.2 Jumper position ......................................................... pag. 22

2.4 Filling of the heating system .................................................. pag. 23

2.5 Burner adjustment.................................................................. pag. 23

2.6 Burner adjustment.................................................................. pag. 24

2.7 Adaptation to the use of other gas ........................................ pag. 26

2.8 Fault finding and reparation ................................................... pag. 27

INSTRUCTIONS FOR THE USER ...................... pag. 28

3.1 Panel board ............................................................................ pag. 28

3.2 Ignition and extinction ............................................................ pag. 30

3.3 Notes....................................................................................... pag. 30

For your own safety, observe these safety instructions.:

PLEASE NOTE:

User tip for the optimum utilisation

and setting of the control(s) plus

useful information.

WARNING

from risk of electric shock.

WARNING

Identifies potentially dangerous

situations.

Technical features and dimensions

- EMC Directive 89/336/EEC dated 3 May 1989 amended by Directive 92/31/EEC dated 28 April 1992;

- European Community’s Low Voltage Directive 73/23/EEC dated 19 February 1973 amended by Directive 93/68/EEC dated 22 July 1993;

The main technical features of the DUA plus B boilers are summarised below:

· 60 litre enamelled upright storage tank with a helical steel heat exchanger;

· Monothermal, copper, high performance heat exchanger;

· Adjustment of maximum output in heating mode;

· Adjustment of the flame modulation as a function of the absorbed power;

· NTC sensor for D.H.W. priority;

· Safety pressure switch for low water level;

· System water inlet tap;

· Storage tank exhaust tap;

· Circulation pump with automatic air vent;

· Filling tank pump with automatic air vent;

· High limit thermostat (105°C);

· Anti-freeze protection;

· 7,5 litre expansion vessel;

· 4 litre sanitary expansion vessel (optional);

· Automatic differential by-pass;

· Control panel with IP X4D insulation protection;

· Led indication of: D.H.W. demand, C.H. demand, voltage presence, burner in operation, temperature scale, faults, chimney sweeper mode;

· Manometer;

· Tap water flow rate restrictor set at 12 litres/min;

· Unlocking of check valves;

· C.H. temperature selector (35 - 85°C);

· D.H.W. temperature selector (35 - 65°C);

· Main selector Winter / Summer / Antifreeze / Only Heating;

· Minimum outer temperature calibration (if an outer sensor is connected);

· Mounting frame with valves for easy hydraulic connections (optional);

· Electronic ignition with double electrode;

· Casing painted with epoxypoliester pouders;

· Flue gas antispillage thermostat (natural draught open chamber version);

· Heating exhaust tap.

1.1- TECHNICAL FEATURES

DUA plus is a wall hung gas boiler with

built-in atmospheric gas burner for heating and D.H.W. production; it is available in the following versions:

DUA plus BTN 28 with natural draught

open chamber

DUA plus BTFS 28 with forced draught

room sealed combustion chamber

All versions have electronic ignition.

DUA plus B boilers are supplied with all control and safety features according to the latest laws in force, and comply with the fundamental requirements of the following EEC directives:

The BEA boilers comply with the fundamental requirements of the following EEC directives:

- Directive Gas 90/396/EEC dated 29 June

1990;

- Yield Directive 92/42 EEC dated 21 May

1992;

fig. 1

182

167

600

870

475

plus

DUA

140

175

69 189

71,5

57 148,5

1.2 - DIMENSIONS

TECHNICAL FEATURES ET DIMENSIONS

view from above

view from below

Technical features and dimensions

fig. 2

fig. 3

DUA plus BTN 28

DUA plus BTFS 28

MRGCF

13 12

9 8

7 6

23 24

27 28 29

RGMCF

13 12 11

25 26

31 32

1.3 - HYDRAULIC CIRCUITS

1 Filling system cock 2 Boiler draining valve 3 By-pass 4 No-return valve 5 Pump 6 Air vent 7 Modulating gas valve 8 Low water pressure switch 9 Ignition electrode 10 Burner injectors 11 Ignition electrode 12 Ionisation electrode 13 Main heat exchanger 14 Smoke safety thermostat 15 Draught diverter 16 Safety thermostat 17 Manual air vent 18 Boiler expansion tank valve inflation 19 Expansion vessel 20 Flow temperature sensor 21 Expansion vessel l. 4 (optional) 22 Heat exchanger draining valve 23 Tank 24 Tank draining valve 25 Magnesium anode 26 Tank temperature sensor 27 Domestic Hot Water flow restrictor 28 Filter 29 C.H. safety valve 30 Boiler safety valve

M C.H. flow 3/4" C D.H.W. outlet 1/2" G Gas inlet 3/4" F D.C.W. inlet 1/2" R C.H. return 3/4"

1 Filling system cock 2 Boiler draining valve 3 By-pass 4 No-return valve 5 Pump 6 Air vent 7 Modulating gas valve 8 Low water pressure switch 9 Ignition electrode 10 Burner injectors 11 Ignition electrode 12 Ionisation electrode 13 Main heat exchanger 14 Smoke pressure nipple 15 Extraction fan 16 Air intake and smoke evacuation duct 17 Microswitch of the smoke pressure 18 Safety pressureswitch of smoke circuit 19 Smoke pressure nipple 20 Safety thermostat 21 Manual air vent 22 Boiler expansion tank valve inflation 23 Expansion vessel 24 Flow temperature sensor 25 Heat exchanger draining valve 26 Expansion vessel l. 4 (optional) 27 Tank 28 Tank draining valve 29 Magnesium anode 30 Tank temperature sensor 31 Domestic Hot Water flow restrictor 32 Filter 33 C.H. safety valve 34 Boiler safety valve

M C.H. flow 3/4" C D.H.W. outlet 1/2" G Gas inlet 3/4" F D.C.W. inlet 1/2" R C.H. return 3/4"

Technical features and dimensions

DUA plus BTN 28

II2H3+

8,9

0,5

3,25

7,5

139,9

0,5

8,98

9,98

11,43

13,33

15,99

187

35 - 65

230/50

X4D

l/min

bar

°C

bar

l/min.

°C

V-Hz

A (F)

°C

g/s

mg/kwh

DUA plus BTN 28

27,9

12,5

89,95

89,89

89,68

87,34

92,87

88,88

2,62 - 2,92

64,6 - 83,4

22,05 - 24,3

126,46

2,3 - 4,6

186

11,12 - 7,13

0,449

DUA plus BTFS 28

28,8

12,9

92,94

92,92

92,04

90,38

94,96

90,74

2,04 - 2,02

60,4 - 69,6

19,51 - 20,55

89,4

2,6 - 5,9

130

11,03 - 6,61

0,489

DUA plus BTFS 28

II2H3+

8,8

0,5

3,25

7,5

139,3

0,5

9,1

10,2

11,7

13,6

16,4

187

35 - 65

230/50

148,5

X4D

1.4 - OPERATIONAL DATA

For some data (NOZZLES - BURNER GAS PRESSURE - DIAPHRAGMS - INPUTS - GAS CONSUMPTIONS) refer to paragraph ADAPTATION TO THE USE OF OTHER GAS on page 26.

1.5 - GENERAL SPECIFICATIONS

(*) Warning: The utilisation of this type of boilers in the "floor heating systems" needs the use of specific equipments (e.g.:

UNICAL Thermic Module) to avoid all risks of smoke condensation within the boiler.

Nominal output

Minimum output

Actual water efficiency at 100 % of nominal load

Minimum water efficiency required at 100 % of nominal load

Actual water efficiency at 30 % of nominal load

Minimum water efficiency required at 30 % of nominal load

Star number (according to Efficiency Directive 92/42/CE)

Combustion efficiency at 100 % of nominal load

Combustion efficiency at minimum load

Heat losses through the casing (min. / max.)

Maximum net smoke température (Ts- Ta)

Massive smoke flow rate (min. / max.)

Air exces (lambda)

NOx (ponderal value according to EN 297/A3+EN 483)

NOx class (ponderal value according to EN 297/A3 + EN 483)

Chimney heat losses with burner in operation (min./max.)

Chimney heat losses with burner shut-off

Boiler category

Minimum water low rate in heating circuit (ΔT 20°C)

Minimum pressure in heating circuit

Maximum pressure in heating circuit

Water content of the primary circuit

Maximum operation temperature in heating mode

Minimum operation temperature in heating mode (*)

Expansion vessel total content

Maximum water content of the heating circuit (max. temp. 90°C)

Minimum pressure in the D.H.W. circuit

Maximum pressure in the D.H.W. circuit

Tank capacity

Specific D.H.W. flow rate ( t 30°C according to EN 625)

Flow rate of the D.H.W. flow restrictor

Contiunuous D.H.W. production with t 45 K

Contiunuous D.H.W. production with t 40 K

Contiunuous D.H.W. production with t 35 K

Contiunuous D.H.W. production with t 30 K

Contiunuous D.H.W. production with t 25 K DHW available at a temp. of 45°C in the first 10 mins of draw-off with storage tank water at 60°C and cold water at 10°C (*) D.H.W. temperature adjustable between

Electrical power supply Tension/Frequency

Supply fuse

Maximum absorbed output

Insulation degree

Net weight (dry)

Installation info

fig. 4

650

960

665

INSTRUCTIONS FOR THE INSTALLER

2.1 - INSTALLATION CONDITIONS

DUA plus is a gas boiler which must be

installed in accordance with the latest regulations or rules in force. For the boiler category, which changes according to the destination country, see page 3.

NOTE:

Observe the corresponding technical rules and the building supervisory and statutory regulations of the country of final use when installing and operating the system. Always ensure that an appropriately specialised company is entrusted with installation, gas supply and flue gas connection, commissioning and power supply, as well as all servicing and repair works. Work on gas conduits and fittings must only be carried out by a registered service provider.

The system must be cleaned and serviced once a year. This includes an inspection of the entire system to see if it is in full working order. Defects and faults must be eliminated immediately. Please note that we can accept no liability whatsoever for loss or injury resulting from unauthorised adjustment or manipulation of the system’s control or regulating devices.

2.2 - INSTALLATION

2.2.1 - PACKING

Dua plus B is packed and delivered in a

strong cardboard box. Once the boiler has been unpacked check that it is intact. The packaging material can be recycled and it must be disposed of accordingly. Keep the packaging out of the reach of children as it represents a choking and suffocation hazard.

UNICAL waives all liability for injury to persons and animals or damage to property resulting from non-observance of the above.

The packaging contains:

- the copper pipe kit for hydraulic connec-

tion of the boiler to the heating and water system and to the gas mains;

- a bag with:

a) installation, use and maintenance hand-

book, b) template for fixing the boiler to the wall, c) 4 screws with dowels to fix the boiler to

the wall, d) for models TFS, a diaphragm for flue gas

exhaust.

Installation info

fig. 5

2.2.3 - ASSEMBLING THE BOILER

Before connecting the boiler to the D.H.W. and heating system pipes, carefully clean the pipes to remove all traces of metal resulting from processing and welding operations as well as any oil and grease which could damage the boiler or jeopardize its operation.

Unical refuses all liability for injury to persons and animals or damage to property resulting from non-observance of the above.To install the boiler:

- Fix with tape the paper template to the wall

- make two Ø 12 holes in the wall and insert the hooks;

- position the junction points for the connection of the gas supply pipe, cold water supply pipe, D.H.W. outlet, CH flow and return in the positions shown by the template.

- fit the boiler onto the support hooks;

- connect the boiler to the gas pipe, domestic cold and hot water pipes, CH flow and return pipes.

- connect to electrical supply.

NOTE:NOTE:

NOTE:

Do not use solvents which couldDo not use solvents which could

Do not use solvents which could damage the components.damage the components.

damage the components.damage the components.

damage the components.

M = C.H. flow 3/4" C = D.H.W. outlet 1/2" G = Gas inlet 3/4" F = D.C.W. inlet 1/2" R = C.H. return 3/4" S = Draining safety valve

MOUNTING TEMPLATE

2.2.2 - POSITIONING OF THE BOILER

Every boiler is supplied with a dedicated "Metallic mounting jig" to allow the correct positioning of the gas, water and C.H. system connections when the hydraulic

system is being laid out and before the boiler is installed.

This mounting jig must be fixed to the wall chosen for the installation of the boiler using

two screws with expanding dowels.

The lower part of the mounting jig allows the correct marking on the wall of the points where the fittings for the gas, C.H. flow and return, D.H.W. and D.C.W. have to arrive.

Determine the position of the boiler taking care:

- of leaving a minimum clearance of 50 mm on both sides of the boiler to allow accessibility for service.

- of a good resistance of the screws supporting the boiler on the wall.

- of avoiding to position the boiler above an equipment whose use could be prejudicial for the boiler (stove with emission of greasy vapours, washing machines, etc...).

IMPORTANT: 350 mm free space must be left between the top of the boiler and the ceiling to allow replacement of the magnesium anode. This condition is met when there is a space of 436 mm between the axis of the holes in the boiler bracket and the ceiling.

The mounting jig allows the completion of all the connections and the making of the soundness test of the full installation without the boiler in place. If the boiler is not put in place immediately, protect the different connections in order to avoid that the mortar and the paint cannot compromise the soundness of the subsequent connections.

Because the temperature of the wall, on which the boiler is fitted, does not rise more than 60 K when the boiler is in operation, there are no special requirements to comply with.

Installation info

2.2.4 - VENTILATION

The boiler must be installed in a suitable room according to the rules in force and particularly:

NATURAL DRAUGHT OPEN FLUE BOILERS (TYPE B11bs and VMC INSTALLATIONS)

The boilers DUA PLUS TN, are open flue boilers and are foreseen for chimney connection: the air for combustion is taken directly from the room in which the boiler is installed. The room can have both a direct ventilation (i.e. with ventilation openings facing outwards) or an indirect ventilation (i.e. with ventilation openings facing an adjacent room) provided that the following requirements are complied with:

Direct ventilation:

- The room has to have a ventilation opening of, at least, 6 cm² /kW of installed input (see input table on par. 2.7) and, in no case, lower than 100 cm² and made directly onto an external wall.

- The opening has to be as close as possible to the floor.

- It should not be possible to close it and it should be protected with a grate not reducing its usefull ventilation section.

- A correct ventilation can be optained also through the addition of more openings, provided the addition of the different sections is not less than that really needed.

- In case it is not possible to make a ventilation opening close to the floor, it will be necessary to increase its usefull section of at least 50%.

- If an open fire is present in the same room it needs an indipendent air supply, otherwise the installation of a type B appliance is not permitted.

- If in the room there are other devices which need air for their operation (e.g. a wall exhauster) the section of the ventilation opening has to be the properly sized.

Indirect ventilation

In case it is not possible to make a room ventilation opening on an external wall, it is possible to have an indirect ventilation, sucting the air from an adjacent room, making an opening in the lowest part of a door. This solution is possible only if:

- The adjacent room is not a bed room

- The adjacent room is not a common part of the building and is not a room with fire danger (e.g. a fuel deposit, a garage, etc..)

FORCED DRAUGHT ROOM SEALED BOILER (TYPE C12 - C32 - C42 - C52 - C62 - C82)

The DUA PLUS TFS are forced draught, room seal-ed boilers; so they do not need particular ventilation openings for the combustion air, in the room in which they are installed.

FORCED DRAUGHT, OPEN FLUE BOILER (TYPE B22)

If the DUA PLUS TFS are installed in a room ac-cording to the chimney configuration on type B22, the same ventilation requirements established in paragraphs Direct

ventilation and Indirect ventilation apply.

2.2.5 -FLUE GAS DISCHARGE SYSTEM

NATURAL DRAUGHT OPEN FLUE BOILERS

Connection to the chimney

A good chimney is very important for the correct functioning of the boiler; it must therefore conform with the following requirements:

- it must be made from waterproof material

and be resistant at the temperature of the flue gas and relative condensate;

- it must have sufficient mechanical

strength and low thermal conductivity;

- it must be perfectly sealed to prevent

cool-ing due to parasite air inlets;

- it must be as vertical as possible and the

end section must have a chimney cap which guarantees efficient and constant evacuation of the combustion products;

- the chimney must have a diameter not

smaller than that of the boiler’s draught diverter; for chimneys with a square or

rectangular section, the internal section must be 10% larger than the section of the connection duct to the draught diverter.

- starting from the draught diverter, the duct must have a vertical section with a length more than twice the diameter, before getting into the chimney.

Direct emission into the atmosphere

Natural draught boilers can discharge combustion products directly into the atmosphere using a duct, which goes through the outside walls of the building, connected to a flue exhaust terminal. The exhaust duct must also comply with the following requirements:

- the sub-horizontal part inside the building must be as short as possible (no more than 1 m);

- for boilers with vertical discharge, such as boilers Dua plus B, there must be no more than 2 direction changes;

- it must receive the discharge from a single boiler;

- the part going through the wall must be protected by a sheath duct; the part of the sheath duct facing the inside of the build-ing must be sealed and the part facing outwards must be open;

- the final section, on which the draught terminal will be fixed, must protrude from the wall of the building for a length of at least twice the diameter of the duct;

- the draught terminal must overlap the connection to the boiler by at least 1.5 m (see fig. 8).

Installation info

fig. 6

fig. 7

600

167

880

Ø 140

182

475

2 Ø min.

Slope min. 3%

1,5 m min.

2 Ø

1 m max.

1,5 m min.

2 Ø

Slope min. 3%

1 m max.

2 Ø min.

> 3 Ø

plus

DUA

plus

DUA

plus

DUA

WARNING:

The boiler is fitted with an automatic safety reset device as protection against spillage of combustion products inside the building. In case of the device operation, the boiler

will remain in lock-out position indicating the

anomaly on the display. After 15 minutes the boiler will be reset automatically.

It is absolutely forbidden to by-pass the smoke thermostat.

If the boiler cuts off regularly, it is necessary to ask a technician for a check of the flue gas exhaust duct. This duct may be obstructed or may be unsuitable for the discharge of flue gas into the atmosphere.

UNICAL refuses all liability for damage caused as a result of incorrect installation, use, modi-

fication of the boilers or for non-observance of the instructions provided by the manufacturer or applicable installation regulations

DIMENSIONS FOR CONNECTING FLUE GAS DUCT

Installation info

fig. 8

The DUA plus B is a forced draught, room seled boiler; so it does not need particular ventilation openings for the combustion air, in the room in whichit is installed.

POSITIONING OF TERMINALS FOR TYPE ‘’C’’ BOILERS

Position of the terminalPosition of the terminal

Position of the terminal

Min. DistancesMin. Distances

Min. Distances

- Under a window A 600

- Under a ventilation opening B 600

- Under a gutter C 300

- Under a balcony (1) D 300

- From an adjacent window E 400

- From an adjacent ventilation opening F 600

- From vertical or horizontal air pipes or drains (2) G 600

- From an external corner of the building H 300

- From an internal corner of the building I 1000

- From the ground or from another floor L 1800

- Between two vertical terminals M 1500

- Between two horizontal terminals N 1000

NOTES

(1) Terminals below a practicable balcony shall be arranged in such a way as to assure that the total run of smokes, from their outlet from terminal up to outlet from balcony external perimeter, including the height of protection baluster, if any, is not less than 2 m. (2) Distances of not less than 500 mm shall be adopted in placing the terminals, due to the proximity to materials subject to the action of products of combustion such as plastic gutters or waterspouts, wooden jetties, etc.) unless adequate screening measures are taken for the said materials.

The forced draught, room seled boilers, normally should evacuate the smokes on the roof of the building.

When, in some country, it is allowed to evacuate on the front of the building, the following distances of the terminals, have to be complied with:

TERMINALS POSITION

Installation info

2.2.5 - SMOKE DISCARGE AND AIR SUCTION DUCTS CONFIGURATION TYPES C12, C32, C42, C52, C82

The DUA plus boiler has been approved for the following air suction and smoke evacuation tipes:

C12

Boiler designed for connection to horizontal exhaust and suction terminals directly into the atmosphere using coaxial or dual ducts. The distance between the air intake duct and the flue gas outlet duct must be at least 250 mm and both end sections must be located within a 500 mm square.

C32

Boiler designed for connection to vertical discharge and suction outlets directly into the atmosphere using coaxial or dual ducts. The distance between the air intake duct and the flue gas outlet duct must be at least 250 mm and both end sections must be located within a 500 mm square.

C42

Boiler designed for connection to collective chimneys including two ducts, one for the suction of combustion air and the other for the exhaust of the combustion products, through coaxial or dual ducts.

The chimney must comply with relevant applicable law provisions.

C52

Boiler with separate combustion air suction and combustion product exhaust ducts.

These ducts can discharge into areas with different pressure. The dual ducts must not be located on two opposite walls.

C82

Boiler designed for connection to an air supply terminal and fitted to an individual or shared chimney.

The chimney must comply with relevant applicable law provisions.

type C12

type C32

type C52

type C82

type C42

Installation info

fig. 10

fig. 9

Ø 100

880

182

600

475

minimo 500

plus

DUA

167

DIMENSIONS FOR CONNECTION OF THE COAXIAL DUCTS

Type C12

The maximum autorised length for the horizontal coaxial pipes is 3 meters; for each supplementary bend the maximum length will be reduced by 1 meter; furthermore the pipe shal have a downward inclination of 1% on the outlet direction in order to avoid the rain enter the pipe.

For installations with horizontal coaxial pipe with length between 1 m, it is necessary to place, inside the fan outlet, the diaphragm supplied with the boiler (see fig. 9).

Type C32

The maximum allowed length of the coaxial vertical pipes is 5 meters, included the roof terminal; for each supplementary bend the maximum allowed length will be reduced by 1 meter.

For installations with coaxial ducts having a length between 1.5 m, it is necessary to place, inside the fan outlet, the diaphragm supplied with the boiler (see fig. 9).

2.2.7 - SMOKE DISCHARGE SYSTEM FORCED DRAUGHT BOILERS

C12: between 0.5 and 1 m

with

diaphragm

Ø 40 L m

ax = 3 m

Neoprene

Diaphragm

C12: between 1.2 and 2.5 m

with diaphragm Ø 40 L max = 3

Diaphragm

gasket

Installation info

fig. 11

fig. 12

600

475

880

120

167

Ø 80

182

plus

DUA

2.2.8 - SMOKE EVACUATION

THROUGH TWO SEPARATE DUCTS Ø 80 (Type B accessories)

NB: The maximum allowed pressure

drop, according to the installation type, must be equal to the value indicated in the installation examples given on page 17.

For installations with smoke evacuation through separate ducts, whose pressure drop value is between 15 Pa and 30 Pa, it is necessary to fit a diaphragm, supplied with the boiler, inside the smoke outlet (see fig. 11).

Diaphragm

Neoprene gasket

Diaphragm

From

ΔΔ

P=40 Pa

DIMENSIONS FOR CONNECTION THE AIR INTAKE AND THE FLUE GAS DISCHARGE WITH DUAL DUCTS

Installation info

fig. 13

500

Hmin. = 165 mm

CONFIGURATIONS FOR SEPARATE PIPES (SUCTION AND OUTLET) Ø 80

Example N.1

Primary air suction from perimeter wall and flue gas discharge on roof.

Maximum allowable pressure loss: 65 Pa

Example N.1

Installation info

fig. 14

135

Hmin. = 165 mm

250 min.

Example N.2

Primary air intake from an outer wall and smoke evacuation through the same wall.

Maximum allowed pressure drop: 72Pa

CALCULATION OF PRESSURE LOSS FOR DISCHARGE & SUCTION DUCTS

Bear in mind the following parameters when calculating pressure losses:

- for each metre of duct with Ø 80 (both

suction and discharge) the pressure loss is 2 Pa;

- for each 90° Ø 80 (R=D) bend with long

radius, the pressure loss is 4 Pa;

- for the Ø 80 L = 0.5 m horizontal air inlet

terminal, the pressure loss is 3 Pa;

- Ø 80 L = 0.6 m horizontal discharge end

section, the pressure loss is 5 Pa;

NB: These values refer to discharges

through original UNICAL non flexible and smooth ducts.

In both of the following examples the hypotized compositions of the intake and evacuation ducts are possible because the total pressure loss is lower than 72 Pa, which is the maximum allowed pressure loss.

Example of check using wide radius bends:

- 15 m duct Ø 80 x 2 = 30 Pa

- 2x90° Ø80 long radius bends 2x4= 8 Pa

- horizontal Ø 80 air inlet terminal = 3 Pa

- horizontal Ø 80 terminal = 5 Pa

Total pressure loss = 46 Pa

Example N.2

Installation info

fig. 17

fig. 15

TSC0210C

ADA0160C

Analyser probes

Smokes

Air

2.2.9 - ON SITE COMBUSTION EFFICIENCY MEASUREMENT

Coaxial ducts (Type A accessories)

To determine combustion efficiency the following measurements must be made:

- the combustion air temperature measured

in hole 2 (see fig. 15).

- the flue gas temperature and CO2 %

measured in hole 1 (see fig. 15).

Make these measurements with the boiler running in a steady state condition.

(Type B accessories) Separate ducts

To determine combustion efficiency the following measurements must be made:

- the combustion air temperature measured

in hole 2 (see fig. 15).

- the flue gas temperature and CO2 %

measured in hole 1 (see fig. 15).

Make these measurements with the boiler running in a steady state

condition.

Analyser probes

2.2.10 - GAS SUPPLY LINE

The gas supply line must have a diameter equal or larger than the one used in the boiler.

Comply with the applicable local installation requirements which shall be considered as having been incorporated in full in this manual. Before opening the internal gas supply system; i.e. before connecting the gas meter, all seals must be checked. If any part of the system is concealed the seals must be checked before the pipes are covered.

The seal test must be conducted using air or nitrogen at a pressure of at least 100 mbar. The commissioning of the boiler also includes the following operations and checks:

- Opening of the gas gate valve and venting of the air contained in the piping and boiler, proceding appliance by appliance.

- Check, with the gate valve of all the appliance

DIAGRAM FLOW RATE/MANOMETRIC HEAD AVAILABLE FOR C.H. SYSTEM

= By-Pass CLOSED = By-Pass OPEN

..............

Flow rate l/h (Q)

Available Manometric Head m c.e.

2.2.11 - HYDRAULIC CONNECTIONS

Before installing the boiler we recommend that the system be cleaned to remove any impurities which could originate from components and which could risk damaging the circulating pump and heat exchanger.

HEATING

The heating flow and return must be connected to the relevant ¾” connections of the boiler M and R (see fig. 5). When determining the size of the heating circuit pipes it is essential to bear in mind the pressure losses induced by radiators, any thermostatic valves, radiator cut-off valves and the configuration of the system. In the boiler, between the flow and return pipes,an automatic bypass device is fitted (a differential valve with a flow rate of about 150 l/h) which guarantees always minimum flow rate through the heat exchanger, also in the case, for instance, that all the thermostatic valves fitted on the radiators, are closed.

Off, that there are no gas leaks. During the 2nd quarter of a hour from the beginning of the test no pressure reduction is to be detected on the gas pressure gauge. If gas leaks have to be found, use only water soap solution or any other specific gas leak detector which can be available on the market. Never look for gas

leaks using a nacked flame.

Installation info

D.H.W. PRODUCTION

Cold water temperature = 15 °C Quantity drawn at 14 litres/min

fig. 19

Drawing temperature °C

Quantity drawn in litres

By-Pass CLOSED

By-Pass OPEN

fig. 18

It is possible to adjust the by-pass by acting onto the adjusting screw (see fig.

18).

D.H.W. (Domestic Hot Water)

Inlet and Outlet and of D.H.W. must be connected to the relevant ½” connections of the boiler C and F (see fig. 5).

The pressure in the water mains must be between 1 and 3 bar (in case of higher pressure it is necessary to fit a PRV (Pressure Reducing Valve).

We recommend that the discharge of the safety valve mounted in the boiler be conveyed into the sewer. If this precaution is not taken, activation of the safety valve may result in flooding of the room where the boiler is installed. UNICAL shall not be held responsible for damage caused by non-observance of this technical precaution.

The hardness of the supply water affects the frequency of the cleaning of the heat exchanger; the opportunity to install a water softning device depends on the characteristics of the water it self.

NOTE: With a water whose hardness is higher than 20°f the use of a softner is strongly recommended

0 50 100 150 200 250 300

2.2.12 - ELECTICAL CONNECTIONS

The electrical connections of DUA plus 30

μtank are shown in the clause ‘’WIRING

DIAGRAMS’’ (par. 2.3 - pag. 20). The boiler must be connected to the mains supply at 230 V - 50 Hz. This connection is to be perfectly done, as foreseen by the IEC and local rules and must be earthed.

This fundamental requirement for safety purposes must be checked; in case of doubt, ask for a professionally qualified technician to check the electrical system. UNICAL disclaims all liability for damage or caused by failure to earth the system.

Gas, domestic water and central heating pipes are not suitable for earthing purposes.

The boiler is supplied with 1.5 m long 3x0,75mm² cord.

PhasePhase

Phase and

Neutral Neutral

Neutral must

compulsory be connected to

PhasePhase

Phase and

NeutralNeutral

Neutral of the supply socket. A double pole switch with a distance between the contacts higher than 3 mm, must be installed upstream the boiler to enable all maintenance operations to be carried out safely.

Installation info

fig. 20

65432 17

7654321

BLUE BROWN

E. RIV.

TEFLON WHITE

ROD

BROWN

BLUE

YEL/GREEN

32 1

GREEN

BROWN

WHITE

BLUE

87654 321

4321

54321

WHITE

BLUE

BLUE BLUE

BROWN

GREEN

VERSION E

TFS

5432 1

PV TL

65432 1

BROWN BLUE YEL/GREEN

BROWN

BLUE

YEL/GREEN

BROWN

E. ACC. 1

TEFL ON R ED

TEFLON RED

V2V1

E. ACC. 2

BLUE

BROWN

BLUE

YEL/ GREEN

DISPLAY PCB

BROWN

TA 1

BLAC K

BLUE

YEL/GREEN

ALIME NTATION

230 V - 50 Hz

54321

GND1

GND2

GND4

ROD

GND5

L1 EXT

SENSOR

7654 321

43217654

321

2 1

A3 A1 A2 A4

TA 2

EVZ

2.3 - ELECTRICAL WIRING

2.3.1 - ACTUAL CONNECTION DIAGRAM

KEY A1…A8 = Utility connectors ROD = Ionization electrode connection

on the main board

Y1 = Room thermostat and outer

sensor connectors Y2 = Voltage connector DK = Pressure switch for low water

level E. RIV. = Ionization electrode E.ACC1 = Ignition el ect rode E.ACC2 = Ignition el ect rode MD = Modulating coil PR = Heating pump PS = Sanitary pump PV = Fan pressure switch (only fan

assisted version) SE = Outer sensor (optional) SS = D.H.W. temperature sensor SR = C.H. temperature sensor TA = Room thermostat (optional) TF = Flue gas antispillage thermostat

(natural draught version) TL = Limit thermostat V = Fan (only fan assisted version) VG = Gas valve JP1 = Jumper for on/off or modulating

chronothermostat selection (see

page 22) JP2 = Jumper for boiler version

selection (natural draught or fan

assisted)

Installation info

fig. 21

AZZURRO

AZZURRO (N)

GIA/VERDE

CAVO PVC 3x0,75 Ø

MARRON E

MARRONE ( L)

GND 1

plus

DUA

MAX

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

-20 °C

10 °C

0 °C

-10 °C

MIN - MAX

GENERAL INFORMATION ON THE ELECTRICAL CONNECTIONS

Access to the supply terminal block

- WARNING! Disconnect power supply

- Remove the front casing.

- Widen the two plastic flaps (A); pull frontwards the panel board and rotate it downwards.

- To get access directly to the connection zone, unscrew the two screws (B) and remove the cover (C); if this isn't enough, unscrew the five screws (D) to get access completely inside the panel board

(act carefully).

Replacement of the supply cable

When replacing the supply cord, the UNICAL original one, Part. code 00610308, must be

used.

- Get access to the supply terminal block Y2 (see previous paragraph).

- Insert the new power supply cord through the extractable cable gland E

- Pul out the terminal block Y2 and make the connections respecting the position and the colours. The female faston of the earthing wire must be introduced on the tab GND 1.

L1= phase = brown - terminal Y2 - 1 N =neutral = bleu - terminal Y2 - 2

= earth = yellow/green - tab GND1

Room thermostat connection (ROOM STAT)

- Get access to the terminal block Y1

- Remove the link between terminals 4 - 5.

- Insert the room thermostat cable TA through the extractable gland, supplied with the boiler, and connect it to the terminals 4 and 5.

- WARNING! If an ON/OFF room stat is used, the jumper JP1 of the modulating PCB must be positioned between pins 2 and 3 (see fig. 23).

External sensor connectionEXT SENS)

- Get access to the terminal block Y1

- Insert the external sensor cable through the extractable cable gland, supplied with the boiler, and connect it to the terminals 2 and 3 of the block Y1; if the cable is of shielded type, then connect the shield to the terminal 1 of the block Y1.

For the connection of the ROOM STAT and the EXT SENSOR, replace the plastic plugs F of the panel board with the cable glands supplied with the boiler.

ACCESS TO THE MODULATING PCB

Front view

Panel board side view

Installation info

2.3.2 - POSITIONING OF THE JUMPERS

fig. 23

JUMPERS ON THE DISPLAY PCB

JP4 : GAS TYPE SELECTION Naturl gas: Jumper on NAT (standard supply position) Liquefied Petroleum Gas: move jumper to LPG position

The standard supply position correspond to the gas type shown on all the labels within the boiler

JP3 : EXTRNAL TEMPERATURE COMPENSATION FOR OUTER SENSOR

Boiler with outer temperature sensor: jumper on

Boiler without outer temperature sensor: jumper on OFF

JP2 : SELECTION OF PUMP OPERATION MODE If pump has to work continuously: jumper on 1 If pump has to stop after an overrun of 5 min since the stop of the heating demande: jumper on pos. 2 (standard supply position)

JP1 : CHRONOSTAT FUNCTION (do not change posion of the jumper) This function is not yet available.

Jumper on (Standard supply position: for a good working keep the jumper in this position).

T°C0123456789

0 32755 31137 29607 28161 26795 25502 24278 23121 22025 20987 10 20003 19072 18189 17351 16557 15803 15088 14410 13765 13153 20 12571 12019 11493 10994 10519 10067 9636 9227 8837 8466 30 8112 7775 7454 7147 6855 6577 6311 6057 5815 5584 40 5363 5152 4951 4758 4574 4398 4230 4069 3915 3768 50 3627 3491 3362 3238 3119 3006 2897 2792 2692 2596 60 2504 2415 2330 2249 2171 2096 2023 1954 1888 1824 70 1762 1703 1646 1592 1539 1488 1440 1393 1348 1304 80 1263 1222 1183 1146 1110 1075 1042 1010 979 949 90 920 892 865 839 814 790 766 744 722 701

Relation between the temperature (°C) and the resistance (Ohm) of the heatin temp. sensor SR and the D.H.W. temp. sensor SR. Example: At 25 °C the nominal resistance is 10067 Ohm - At 90 °C the resistance is 920 Ohm.

TABLE OF THE RESISTANCE VALUES ACCORDING TO THE TEMPERATURE OF THE HEATING SENSOR (SR) AND D.H.W. TEMPERATURE SENSOR (SS)

NAT

GPL

OFF

JP4

JP3

JP2

JP1

POSITIONING OF THE JUMPER

Installation info

fig. 23

boiler safety valve

Filling cock

tank draining valve

Adjustable by-pass

manometer

boiler draining valve

2.4 - FILLING THE SYSTEM

After completing all the connections of the system the heating circuit can be filled. This filling operation must be performed with care as follows:

- open the air vents of the radiators and check that the automatic air vent in the boiler is works properly;

- gradually open the water tap and check operation of any automatic air vents installed in the system;

- close the air vents on the radiators as soon as water comes out;

- use the pressure gauge on the boiler to check that the pressure has reached the value of 0.8/1bar;

- close the water inlet tap and then release the air again through the radiator air vents;

- after switching on the boiler and after the system has reached the correct temperature, stop the pump and repeat the air relief operations;

- let the system cool down and then adjust the water pressure to 0.8/1 bar.

This must be performed when the system is cold. Use the temperature and pressure gauge on the boiler to read the pressure value of the circuit.

WARNING

The minimum water pressure switch does not give electrical impulse to the burner to ignite when the pressure is lower than 0.4 bar. The pressure of the water in the C.H. system must not be lower than 0.8/1bar; if this value is lower use the water filling tap on the boiler to adjust the pressure. This must be performed when the system is cold. Use the temperature and pressure gauge on the boiler to read the pressure value of the circuit.

NB: NB:

NB:

AfAf

ter a given period of inactivityter a given period of inactivity

ter a given period of inactivity

and without electrical supply theand without electrical supply the

and without electrical supply the pump could be blocked.pump could be blocked.

pump could be blocked.pump could be blocked.

pump could be blocked. Before switching on the boiler it isBefore switching on the boiler it is

Before switching on the boiler it isBefore switching on the boiler it is

Before switching on the boiler it is important to restart the pump asimportant to restart the pump as

important to restart the pump asimportant to restart the pump as

important to restart the pump as follows:follows:

follows:follows:

follows:

- loosen the protection screw in the centre of the pump motor,

- insert a screwdriver in the hole and then manually rotate the pump shaft clockwise.

Once the pump has been restarted tighten the protection screw and check that there are no water leaks.

WARNING

Once the protection screw hasOnce the protection screw has

Once the protection screw has been removed a little water maybeen removed a little water may

been removed a little water maybeen removed a little water may

been removed a little water may leak out. Before replacingleak out. Before replacing

leak out. Before replacingleak out. Before replacing

leak out. Before replacing the casing of the boiler dry any wetthe casing of the boiler dry any wet

the casing of the boiler dry any wetthe casing of the boiler dry any wet

the casing of the boiler dry any wet surfaces.surfaces.

surfaces.surfaces.

surfaces.

- there are no gas leaks;

- the external mains switch is on;

- the boiler’s safety valve is not locked;

- there are no water leaks.

SWITCHING ON AND OFF

To switch on and off the boiler follow the indications in the “Users’ Instructions”.

- the supply voltage of the boiler is 230 V-

50 Hz;

- the system is correctly filled with water

(pressure at the gauge 0.8/1 bar);

- any gate valves of the system are open;

- the mains gas corresponds to that with

which the boiler has been adjusted; otherwise convert the boiler to use the gas available on site (see: “MODIFICA TION FOR OTHER GASES “):

this operation must be performed by qualified technicians;

- the gas supply taps are open;

2.5 - STARTING THE BOILER

PRELIMINARY CHECKS

Before starting the boiler check that:

- the boiler installation has been made in

accordance with all the applicable regulations concerning water and gas installation, smoke evacuation and electrical installation

- the flue gas exhaust duct and its

terminal are installed correctly: when

the boiler is switched on there must be no leakage of any combustion products from any seals;

Adjustment info

fig. 25

2.6 - ADJUSTING THE

BURNER

All the instructions below are for the exclusive use of qualified technicians. All the boilers leave the factory adjusted and tested. If it is necessary to change the adjustment due to changes in the gas or adaptation to the supply network conditions, it will be also necessary to re-adjust the gas valve.

Attention: during this re-adjustment do not draw any Domestic Hot Water.

For this reason it’s necessary to know the boiler operation in service mode. In order to activate this function, push and keep hold the service push button, on the control panel, for 3 seconds: the service mode green led will be continuously .lighted

( continuous)

and the boiler will

operate at the maximum capacity. Then push once again the same button: the service mode green led will start blinking

( blinking)

. The service mode function

remains active for 15 minutes. For cleaning this function before this fixed period, push the reset button: the service

mode led will switched off

( off).

. To correctly adjust the gas valve, follow the steps below:

A) Maximum output adjustment

- check the value of the supply pressure

(see table NOZZLES - PRESSURES);

- Remove the cover (A) protecting the

pressure regulator on the top of the modulating coil.

- Connect a manometer at the outlet gas

valve pressure nipple.

- Activate the service mode function to

the maximum capacity (service mode led continuous lighted).

- When the burner is ON, check that the

“MAXIMUM” pressure value corresponds to that indicated on the table “NOZZLES

- PRESSURES”:

- Adjust, eventually, the value rotating the

“C” nut (fig. 25) by clockwise rotation the gas pressure increases, by anticlockwise rotation the gas pressure decreases.

B) Minimum output adjustment

- Operate the boiler in service mode at

minimum output (service mode led blinking).

- When the burner is ON, check that the

“MINIMUM” pressure value corresponds

to that shown on the table “NOZZLES

PRESSURES”:

- Adjust, eventually, the value by keeping

locked the ‘’C’’ nut with a 10 mm open wrench and rotating the “B” screw (fig.

25) by clockwise rotation the gas

pressure increases, by anticlockwise rotation the gas pressure decreases.

C) Ending of basic adjustments

- check the min. and max. pressure values

of the gas valve by acting the service mode

- if necessary make any fine adjustments

- Clear the service mode function by

pushing the reset button or switching off.

- Remove the plastic pipe from pressure test nipple and close the inner screw;

fig. 24

Carry out the adjustment Min. output blocking the position of the retaining nut “C” with a 10 mm. spanner to avoid uncalibration and use a scewdriver on the “B screw

- Use soap solution tocheck for gas leaks.

Adjustment Max. output “C” retaining nut with 10 mm. wrench

SERVICE MODE AT MAX CAPACITY

MIN - MAX

SERVICE MODE AT MIN CAPACITY

SERVICE MODE DISABLED (BEFORE 15 MINUTES)

MIN - MAX

MP =

pressure test nipple

PRESSURE TEST NIPPLE

MODULATING COIL

GAS VALVE

Outlet pressure test nipple

Inlet pressure test nipple

B = Minimum pressure adjust. screw

(red)

C = Maximum pressure adjust. nut

(wrench 10 mm)

Adjustment info

fig. 27

fig. 26

1612 1713 1814 1915 20 21 2522 2623 2724 28

BTFS 28

PROPAN

BUTAN

NAT. GAS

Power supply (kW)

Burner pressure (mbar)

CAP

CH - POWER

1612 1713 1814 1915 20 21 2522 2623 2724 28

BTN 28

PROPAN

BUTAN

NAT. GAS

Power supply (kW)

Burner pressure (

bar)

2.7 - ADAPTING THERMAL POWER TO THE HEATING SYSTEM

With the heating system cold. Connect the pressure gauge to the burner

as shown in fig. 24, switch on the boiler in heating mode and proceed as follows.

- Wait about two minutes to allow the pressure to reach the operating value.

- Read the pressure measured and check that the thermal power generated by the boiler suits the installation requirements.

- If necessary – but this is not compul- sory – you can regulate the potentiometer CH POWER on the modulation board to adjust the thermal power to the heating system. Turn the potentiometer clockwise (seen from the front) to increase the pressure or anticlockwise to decrease it.

Note

Since the boiler is the modulating type, it automatically adapts the thermal power to the features of the heating system. By operating potentiometer CH POWER you effectively limit the maximum power of the boiler and hence its pickup capacity.

Using the pressure/thermal power graph (fig. 26)

Assuming that the heating system has a total absorption of 18 kW, using the graph in figure you can determine the maximum pressure at which the burner can be set.

Example 1

If the boiler runs on methane gas, adjust the potentiometer CH POWER to set the pressure to 7,3 mbar for version TN and

to 7,1 mbar for version TFS.

Example 2

If the boiler runs on butane gas, adjust the potentiometer CH POWER to set the pressure to 12,5 mbar for version TN and

to TFS.

Example 3

If the boiler runs on propane gas, adjust the potentiometer CH POWER to set the pressure to 15,3 mbar for version TN and

to 15,5 mbar for version TFS.

GAS PRESSURE BURNER DIAGRAM CORRESPONDING TO THE SYSTEMS OUTPUT

Adjustment info

fig. 28

DUA plus BTN 28

Metano (G20)

Propano (G31)

Butano (G30)

12,5 - 27,9

14,5 - 31

1,30

0,76

2,3

7,8

5,8

9,7

34,3

27,3

1,53 m³/h

1,13 kg/h

1,14 kg/h

3,28 m³/h

2,41 kg/h

2,44 kg/h

DUA plus BTFS 28

Metano (G20)

Propano (G31)

Butano (G30)

12,9 - 28,8

14,5 - 31

1,30

0,76

1,9

7,7

10,6

35,3

27,6

1,53 m³/h

1,13 kg/h

1,14 kg/h

3,28 m³/h

2,41 kg/h

2,44 kg/h

2.8 - MODIFICATION FOR

OTHER GASES

The boilers are manufactured for the type of gas specifically required upon order. Any subsequent conversion must be performed by qualified technicians who will use the kits supplied by Unical and perform the conversion and required adjustments for correct preparation of the boiler for use.

To convert the boiler from one type of gas to another proceed as follows:

for conversion from natural gas to LPG

- remove the main burner;

- disassemble the 15 injectors "

1"of the main burner and replace them with those with a diameter corresponding to the new type of gas (see table “INJECTORS PRESSURES”);

- reassemble the main burner;

- position the jumper on the modulation PCB in the panel board as shown in fig. 23

- remove plug ‘’A’’ (fig. 25) on the gas valve and fully tighten max pressure adjustment nut ‘’C"

- check the pressure value upstream the gas valve (see table “INJECTORS PRESSURES”) and adjust the min. pressure of the burner as shown in section " ADJUSTING THE BURNER”, by screwing the nut "B" to increase or unloosing the nut "B" to decrease the burner pressure.

- check that the burner is functioning properly;

- check that there are no gas leaks.

- tighten and seal the plug “A” (fig. 25) of the modulating coil;

- when the conversion is completed, fill in the label, supplied with the kit, with the information required and stick it onto the boiler alongside the data plate.

for conversion from LPG to natural gas

- remove the main burner;

- disassemble the 15 injectors of the main burner and replace them with those with a diameter corresponding to the new type of gas (see “INJECTORS PRESSURES”);

- reassemble the main burner;

- get access to the modulating PCB inside the panel board and position the jumper shown in thefig. 28;

- remove plug ‘’A’’ (fig. 25) from the gas valve modulating coil and adjust the maximum and minimum output s described in paragraph 2.6;

NAT

GPL

JP4

- check that the burner is functioning properly;

- check that there are no gas leaks.

- tighten the screw “A” of the plug of the gas governor (fig. 25);

- when the conversion is completed, fill in label, supplied with the kit, with the information required and stick it onto the boiler alongside the data plate.

NOZZLES - DIAPHRAGMS - PRESSURES - GAS FLOW RATES

The pressures at the burner indicated in the following table must be checked after the boiler has been operating for 3 minutes.

Type of gas

Supply

pressure

(mbar)

No. of

Nozzles

Diaphragme

(mm)

Nozzles

(mm)

min.

(mbar)

max

(mbar)

Burner pressure

max.

min.

Gas

consumption

Output

min. - max

(kW)

Input

min. - max

(kW)

Type of gas

Supply

pressure

(mbar)

No. of

Nozzles

Diaphragme

(mm)

Nozzles

(mm)

min.

(mbar)

max

(mbar)

Burner pressure

max.

min.

Gas

consumption

Output

min. - max

(kW)

Input

min. - max

(kW)

POSITIONING OF THE JUMPER

Service info

2.9 – FAULT FINDING CHART AND POSSIBLE SOLUTIONS

In case of fault lamp lighting depress the Reset push button and, while kipping it depressed, look at the error code given by the flashing leds. Note: The error code is given by the combination of two, three, four of five leds, flashing on the temperature scale.

SIGNIFICATION OF THE ERROR CODE

Fault on the outer temperature sensor (if connected)

POSSIBLE SOLUTION

The control of the flow temperature by the outer sensor is non active. Call the After Sale Service

BOILER STATUS

This fault does not cause the locking of the boiler.

SIGNIFICATION OF THE ERROR CODE

Faulty flame control PCB

POSSIBLE SOLUTION

Replace the ignition and/or modulating

PCB

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Fault on the gas valve modulation system (coil interrupted)

POSSIBLE SOLUTION

Replace the gas valve modulation coil, after checking of the harness, the supply tension and the gas pressure.

BOILER STATUS

Chaudière fonctionnant à la puissance mini.

SIGNIFICATION OF THE ERROR CODE

The air pressure switch is faulty or in short circuit (only for TFS version)

POSSIBLE SOLUTION

Inspect the air pressure switch operation

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Too high boiler temperature

POSSIBLE SOLUTION

Make sure the pump is properly operating and the heat exchanger is clean inside

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Fault on the smoke evacuation system; after 15 min there is an automatic reset.

POSSIBLE SOLUTION

For TN version: check the chimney draught For TFS version: ascertain the good operation of the fan and its air pressure switch. Depress the Reset button.

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

The water pressure within the installation is below 0.5 bar

POSSIBLE SOLUTION

Reinstate the water pressure through the filling valve (accessible also to the user) and look for possible water leaks. If the problem is not solved call the After Sale Service.

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Probable freezing of the primary heat exchanger; temperature below 2°C detected by the SR or SS sensors.

POSSIBLE SOLUTION

Cut the power supply, close the gas valve and call the After Sale Service.

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Fault on the DHW temperature sensor (SS)

POSSIBLE SOLUTION

Ascertain that the SS sensor has the right resistance values shown on the table of the resistance values and it harness is correct (see table on page

14)

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Fault on the CH temperat. sensor (SR)

POSSIBLE SOLUTION

Ascertain that the SR sensor has the right resistance values shown on the table of the resistance values and its harness is correct (see table on page

16).

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Alteration of factory parameters

POSSIBLE SOLUTION

None. Replace the modulating PCB

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Fault on the modulation system of the gas valve.

POSSIBLE SOLUTION

Check first the modulating coil or its harness are not earthed or in short circuit: if this is the case replace them. If no result, replace the modulating PCB.

BOILER STATUS

The boiler is in lockout position

SIGNIFICATION OF THE ERROR CODE

Main PCB (modulation) is damaged.

POSSIBLE SOLUTION

Cut and reinstate the power supply to the boiler: if no result, replace the main PCB.

BOILER STATUS

The boiler is in lockout position

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

SIGNIFICATION OF THE ERROR CODE

Intervention of the safety thermostat

POSSIBLE SOLUTION

Make sure the water is circulating through the heat exchanger and the safety thermostat TL and its harness are not interrupted. Check as well the CH temperature sensor (SR).

BOILER STATUS

The boiler is in lockout position

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

Service info

fig. 29

B D

plus

DUA

MAX

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

-20 °C 10 °C

0 °C

-10 °C

MIN - M AX

A = Mode selector: Heating only- Heating + D.H.W.

- Antifrost - D.H.W. only B = Heating temperature adjusting knob C = D.H.W.temperature adjusting knob D = Thermometer E = Signal lamp of heating temperature scale

F = Signal lamp of D.H.W. temperature scale G = Power ON signal l

amp (antifrost)

H = Burner in operation signal lamp I = Fault indication lampe L = Burner lockout warning lamp M = Manual reset button

3.1 - PANEL BOARD

N = Special functions button (for service purposes) O = Special functions signal lampe

(for service purposes)

P = Outer temperature selector (opérational only

if outer temperature sensor is fitted).

USER'S INSTRUCTIONS

By acting on the selector the operation mode is choosen :

CENTRAL HEATING ONLY

With the mode selector in this position the boiler works for Central Heating only.

CH & DHW

With the mode selector in this position the boiler works for Central Heating and Domestic Hot Water production

MODE SELECTOR: CH ONLY - CH & DHW ANTIFROST - DHW ONLY

D.H.W. TEMPERATURE ADJUSTING KNOB

With this knob it is possible to set the maximum desired temperature in the boiler. The setting range of this temperature is between a minimum of 35°C and a maximum of 65°C.

By rotating COUNTER-CLOCKWISE this knob a minimum temperature of 35°C is reached.

By rotating completely CLOCKWISE this knob a maximum temperature of 65°C is reached.

D.H.W. only

With the mode selector in this position the boiler works for D.H.W. only.

HEATING TEMPÉRATURE ADJUSTING KNOB

With this knob it is possible to set the maximum desired temperature in the heating circuit. The setting range of this temperature is between a minimum of 35°C and a maximum of 85°C.

By rotating COUNTER-CLOCKWISE this knob a minimum temperature of 35°C is reached.

By rotating completely CLOCKWISE this knob a maximum temperature of 85°C is reached.

MAX

ANTIFROST

With the mode selector in this position the boiler is not in operation: the antifrost protection on the heating circuit only is operational.

The antifrost protection system is operational only if the boiler is feeded with gas and electrical supply.

Service info

MANOMETER

It shows the water pressure inside the heating circuit, whose value, in cold condition,should not be lower than 0,8/1 bar.

Note that if the pressure decreases below 0,4/0,6 bar the boiler goes into lockout, not allowing the ignition of the burner. In this case reinstate the minimum required filling pressure (0,8/1 bar) following the instructions given on figure 23.

POWER ON SIGNAL LAMP

The function of this GREEN lamp is to show that the power to the boiler is ON; to get the boiler ON, position the "A" switch on "I" position.

BURNER IN OPERATION SIGNAL LAMP

The function of this GREEN lamp is to show the proper operation of the burner

FAULT INDICATION LAMPE

The function of this RED lamp is to show an operation fault. By depressing on the RESET button (N) it is possible to see the error code given by the combination od the flashing leds. See paragrapf 2.9 "FAULT FINDING AND REPARATIONS".

BURNER LOCKOUT WARNING LAMP

La fonction de ce témoin (ROUGE) est de signaler l’intervention du dispositif de mise en sécurité du brûleur.

MANUAL RESET BUTTON

This button allows the re-establishment of the boiler operation after a lockout of the burner control and to know the error code given by the combination of the flashing leds (burner lockout warning lamp). (témoin de défaut allumé).

SPECIAL FUNCTIONS BUTTON (FOR SERVICE PURPOSES)

This button allows the activation of the SERVICE mode. (see paragraphe 2.6 "Burner adjustment). To reset this mode before the expiring time depress on the manual reset button. WARNING! OPERATIONS RESERVED ONLY TO SERVICE TECHNICIANS.

SPECIAL FUNCTIONS LAMP (FOR SERVICE PURPOSES)

The function of this GREEN LAMP is to indicate the activation of the SERVICE mode: Continuous ON led = Max output for 15 min. Flashing led = Minimum output for 15 min.

OUTER TEMPERATURE SELECTOR (OPERATIONAL ONLY IF OUTER SENSOR IS FITTED

Si the kit outer sensor is fitted, it is possible, through this button, to set an outer temperature value between -20°C (completely counterclockwise) and 10°C

(completely clockwise). If the outer temperature is equal or lower than the one selected by the selector "Q" the boiler temperature will be the one adjusted on the "C" button. If the outer temperature is higher than the one selected by the selector "Q"the boiler temperature will decrease linearly, independently from the one adjusted on the "C" button.

WARNING! OPERATIONS RESERVED ONLY TO SERVICE TECHNICIANS.

MODULATING ROOM THERMOSTAT

Warning: The mounting of a modulating

room thermostat imply the modification of the functions of the heating temperature adjuster (C) and D.H.W. temperature adjuster (D). Refer to the specific instructions supplied with the modulating thermostat.

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

Through the thermometer scale of the panel board it is possible to verify: on the L.H. side scale the flow température of the heating circuit, (F green led ON); on the following example the temperature will be 80°C.

on the R.H. side scale the outlet température of the D.H.W. (G green led ON); on the following example the temperature will be 55°C.

On both cases, when two leds are ON the temperature value will correspond to the half of temperature difference betwee the two ON leds.

80° 60°

65°

70° 55°

60° 50°

50° 45°

40° 40°

30° 35°

20°

Manometer

THERMOMETER

75°C

57,5°C

Service info

3.3 - IMPORTANT SUGGESTIONS AND NOTES

According to the national laws the service of the heating appliances is compulsory.

This service consistes, as a minimum, of an annual systematic visit, during which the serviceman will control the safety equipment and will make the cleaning of the combustion circuit of the boiler.

This annual visit must be conducted within the frame of a service contract, whose different variants can include all or part of the interventions concerning the deplacement, the manpower and the spare parts.

Only persons professionally qualified can

perform interventions on the gas valve adjustment.

Check regularly the filling pressure of the heating system through the manometer, and, if necessary, reinstate the minimum pressure value (0.8/1 bar in cold condition).

When the boiler stays without been used for a long period, before putting the boiler in operation make sure the pump is not jamed. To make it free, if necessary, remove the plug on the motor axis, put a screwdriver in the slot foreseen on the motor shaft end and try to rotate it manually, clockwise.

Once this dejamming operation has been concluded, replace the protecting plug and make sure there are no water leaks.

This operation has to be made, preferably, by the Unical Service Center charged for maintenance of the boiler.

The hardness of the domestic water conditions the frequency of the cleaning of the coil heat exchanger. The convenience of water treatment must be examined on the base of the water characteristics.

N.B. If the water hardness is higher than 20°f (french), the adoption of a water softer is strongly recommended.

FROST PROTECTION

If the boiler is connected to the mains and the main switch "A" is in the antifrost position, the heating pump is put into operation, for a few seconds, every day, in order to impede the pump jamming.

The boiler is equipped with an automatic antifrost protection system: this system is operational when the temperature detected by the flow temperature sensor falls below 7°C by switching on the heating pump.

Below 5°C, the burner and the pump are switced on, untill the temperature of 15°C, is reached with a 15 min. maximum time limit.

After that, burner and pump are swiched off. This cycle will be repeated, if necessary.

3.2 - IGNITION AND EXTINCTION

BOILER IGNITION

Position the main switch"A" on "I" position .

SUMMER mode (D.H.W.production only)

Select the SUMMER operation mode acting on the selector "B". Turn the temperature adjusting knob "D" on the desired value. By CLOCKWISE rotation the maximum temperature is achieved.

WINTER mode (Heating and D.H.W. production)

Select the WINTER operation mode acting on the selector "B". Turn both, the heating temperature adjusting knob "C" and the D.H.W. temperature adjusting "D" on the desired values.

By CLOCKWISE rotation the maximum temperature is achieved.

HEATING mode (Heating only is activated)

Select the HEATING only operation mode acting on the selector "B". Turn the temperature adjusting knob "C" on the desired value. By CLOCKWISE rotation the maximum temperature is achieved.

The boiler gives always the priority to the D.H.W. mode (see SUMMER operation). Once the D.H.W. demande is satisfied, if the room thermostat asks for heat, the boiler goes to HEATING mode. During the heating operation mode the boiler switches ON and OFF controled by the room thermostat and by the electronic P.C.B. of the panel board. The electronic control built-in the panel board, depending on the detected temperature difference between the one adjusted on the knob and the one mesured,

puts the burner into operation plus or minus frequently in order to satisfy very quickly the heat demande by the room thermostat.

ANTIFROST mode

Select, by acting on the selector "B" the

position (Antifrost)

NB: The signal lamp "H" is ON..

COMPLETE EXTINCTION OF THE BOILER

Cut the elctrical power supply to the boiler acting on the main switch "A" (position O).

If, for any reason (lack of gas or electricity), the antifrost protection system does not work and the temperature detected by the flow temperature sensor falls below 2°C, the operation of the burner is automatically inhibited until the detected temperature rises above 5°C.

This system protects the boiler and the eventual DHW tank from freezing, but it does not protect the C.H. and sanitary circuits. Moreover special anti-freeze products suitable for the multimetal installations can effectively protect the heating system from the freeze.

Do not use the anti-freeze products for car's engines because they can damage the water sealing gaskets.

Note The anti-freeze protection device system will start running only if both the electrical and gas supply of the boiler are left connected.

Information for the user The user can gain access only to the parts of the boiler which can be reached without the need of tools. It is therefore forbidden to disassemble the outer casing of the boiler and tamper with the internal parts.

Service info

AG S.P.A.

46033 casteldario - mantova - italia - tel. 0376/57001 (r.a.) - fax 0376/660556

www.unical.ag - info@unical-ag.com

The Unical declines every responsibility for the possible inaccuracies if owed to errors of transcript or press. Also reserves the right to bring those changes that it will hold necessary to it own products or profits, without jeopardizing its essential characteristics.

Unical DUA plus BTN 28 Installation And User Instruction Manual

Specifications and Main Features

Frequently Asked Questions

User Manual