Duplex Operating Manual

7/31/2019 Duplex Operating Manual

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GAS FIRED HIGH EFFICIENCYLOW NOx BOILERS

SINGLE UNIT OUTPUTS 204 kW-472 kW

INSTALLATION & OPERATINGINSTRUCTIONS

Please contact the Technical Department if further clarification on any point is required.

35 Nobel Square

Basildon

Essex

SS13 1LT

01268 591010 Phone

01268 728202 Fax

V. 01/01/2000GR


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INDEX1

DESCRIPTION

SECTION ONE : INTRODUCTION

1.1 RECOMMENDATIONS

1.2 FIRST FIRING

1.3 USE AND MAINTENANCE

SECTION TWO : STANDARDS

2.1 CERTIFICATES

SECTION THREE : GENERAL REQUIREMENTS

3.1 REQUIREMENTS SUMMARY

3.2 SCALING AND CORROSION

3.2.1 OLD INSTALLATIONS

3.2.2 NEW INSTALLATION

3.3 THERMAL SHOCK

3.4 WORKING PRESSURE

3.5 FLUE SYSTEM

3.6 VENTING


SECTION FOUR : DESCRIPTION

4.1 SECTION AND PLAN ELEVATION OF DUPLEX BOILER

4.1.1 DUPLEX BOILER MODELS DUPLEX - 290, 360

4.1.2 DUPLEX BOILER MODELS DUPLEX - 430, 500

4.2 HEAT EXCHANGER

4.3 BURNER

4.3.1 KIT PILOT BURNER AND CONTROL FLAME

4.3.2 MAIN BURNER

4.4 GAS CONNECTION

4.5 CONTROL PANEL

4.6 BOILER FLUEWAY SYSTEM

4.7 POSITION OF THE VARIOUS COMPONENTS

4.8 TECHNICAL DETAILS

4.9 DIMENSIONAL DATA


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INDEX2

DESCRIPTION

4.10 ELECTRICAL DETAILS

4.10.1 SATRONIC CONTROL SYSTEM

4.10.2 ELECTRICAL WIRING DIAGRAM FOR DUPLEX BOILER, MODELS 220-430

4.10.3 ELECTRICAL WIRING DIAGRAM FOR DUPLEX BOILER, MODEL 500

4.11 MANUFACTURING BOILER LABEL

SECTION FIVE : INSTALLATION

5.1 THE BOILER ROOM

5.2 AIR SUPPLY & VENTILATION

5.2.1 AIR SUPPLY BY NATURAL VENTILATION

5.2.2 AIR SUPPLY BY MECHANICAL VENTILATION

5.3 BOILER BASE

5.4 MODULAR CONNECTION

5.5 ELECTRICAL CONNECTION

5.6 MOUNTING THE BOILER

5.7 SYSTEM WATER

5.7.1 CLEANSING OF OLD SYSTEMS

5.7.3 WATER QUALITY

5.8 WATER FLOW RATE AND TEMPERATURE RISE

5.9 OPERATING WATER TEMPERATURES

5.10 BOILER HYDRAULIC RESISTANCE

5.11 HYDRAULIC CONNECTIONS

5.11.1 INERTIAL TANK

5.12 SYSTEM SCHEMATICS

5.12.1 TYPICAL SINGLE BOILER INSTALLATION

5.12.2 TYPICAL INSTALLATION OF SINGLE BOILER (DHW OR A VERY OLD SYSTEM)

5.12.3 TYPICAL MULTIPLE INSTALLATION (HEATING, DHW)

5.12.4 TYPICAL MULTIPLE INSTALLATION, FOR DHW PRODUCTION, OR A VERY OLD SYSTEM, OR AHEATING SYSTEM OPERATING AT LOW TEMPERATURES

5.13 GAS SUPPLY


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INDEX3

DESCRIPTION

5.14 FLUE SYSTEM

5.14.1 POSSIBLE FLUE CONNECTION FOR BOILER MODEL DUPLEX-220 TO DUPLEX-430

5.14.2 FLUE OUTLET MODEL DUPLEX-500

SECTION SIX : START UP AND CONTROL

6.1 PRE-START CHECKS

6.2 MEASURE INSTRUMENTS

6.3. PREVIOUS CHECKINGS ON THE BOILER

6.4 ADJUSTING PILOT BURNER

6.4.1 CHECKING THE PILOT BURNER

6.4.2 CHECKING THE COMBUSTION OF PILOT BURNER

6.5 PRIMARY AIR DAMPER MOTOR

6.6 LOW - HIGH FIRE DELAY TIMER

6.7 FLUE DAMPER

6.8 ADJUSTMENT OF SECOND STAGE (HIGH FIRE)

6.9. ADJUSTMENT OF FIRST STAGE (LOW FIRE)

6.10 WARNINGS ON COMBUSTION HIGH AND LOW FIRE :

6.11 READINGS ON THE BOILER

SECTION SEVEN : FAULTS DURING OPERATION

7.1 POOR COMBUSTION

7.2 FAULTS THAT CAUSES THE BOILER NOT TO WORK

7.2.1 WHITE SECTOR.

7.2.2 BLUE SECTOR.

7.2.3 RED SECTOR.

7.2.4 YELLOW SECTOR

7.2.5 GREEN SECTOR

7.2.6 GREEN SECTOR

SECTION EIGHT : MAINTENANCE

8.1 CLEANING THE BURNER AND THE COMBUSTION CHAMBER

8.2 CLEANING THE HEAT EXCHANGER

8.3 CHECKING BOILER

SECTION NINE : LIST OF BOILERS COMPONENTS


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SECTION ONEINTRODUCTION

The DUPLEX boiler is a product made by a manufacturer of more than thirty yearsexperience in the heating market. The policy behind the development of the DUPLEXboiler is to provide an appliance which gives the benefits of space saving, reliability, highefficiency and reduced harmful emissions.

The DUPLEX boiler is constructed from high grade materials to ensure a long and efficientservice life.The DUPLEX boiler is a high-efficiency boiler:

- CERTIFICATE CE, As gas boiler, according to European Directive 90/396/EEC

- HIGH EFFICIENCY: The DUPLEX boiler obtains combustion efficiencies between 94 -96% nett, therefore it has obtained the certificate CE of 3 stars (***). CertificateAFNOR Nr. 49AR001R according to directive 92/42/EEC. The flue gas temperaturesare about 90

0C in the low fire stage, and below 120

0C in the high fire stage.

- HIGH OUTPUT: Five models offering 204, 275, 340, 408 and 472 kW

- CERTIFICATE OF COMBUSTION LOW NOX: The DUPLEX boiler has been grantedthe " Combustion Label Clean", Certificate GASKEUR,

-

-

100% PREMIX COMBUSTION

- HIGH / LOW FIRE: Each DUPLEX boiler has a 2 stage burner system which, accordingto demand from external system controls, will operate at either 60% or 100% of output.This allows closer matching of burner power to varying system loads, and avoidsnuisance cycling. The burner output is adjusted via a damper motor driven system,comprising gas and air interlinked butterfly dampers.

- COMPACT DIMENSIONS: The DUPLEX boiler is designed around a unique multi watertube heat exchanger, which provides an exceptional heat transfer surface area. Thisallows high output to dimension ratio to be achieved, and creates an appliance which is

ideal for applications where plantroom space is restricted. Space saving due to thereduced dimensions of the boiler. Foot prints less than 0.5 m2, and heights less than1.3 m.

- LOW GROSS WEIGHT: Saving of transportation by its reduced weight anddimensions. A boiler of heat output of 472 kW has a weight of 350 kg.

- Saving of movement and installation.

- Reduction of the heat losses by boiler radiation. Thanks to its reduced dimensions (1/3of a conventional boiler) it obtained an important reduction of the radiant surface of the

boiler.


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- COMPREHENSIVE CONTROL AND INSTRUMENTATION: The functions of the boilerare managed by a comprehensive control centre which employs industry standardcomponents and provides full operational temperatue and safety control, as well as

monitoring of burner status, temperatures and running hours, all housed in a user andservice engineer friendly panel at the top of the appliance.

- FULLY AUTOMATIC IGNITION: Electronic ignition. Flame Rectification Control . Pilotonly acts as support in the starting of the boiler.

- REMOTE INDICATION: As an optional extra, the boiler control panel can provide voltfree alarm connection points for burner lockout, overheat trip & burner run. Easilyconnection to BMS or similar remote monitoring panel.

- LOW WATER PRESSURE DROP.

- DUPLEX boilers can be used as individual appliances or in multi or modularconfiguration to accurately and efficiently meet system loads.

- DELIVERY: DUPLEX boilers are fully factory assembled and tested and require no siteassembly. The product is delivered to site packed within a sturdy pallet-mounted crate.

1.1 RECOMMENDATIONSThese instructions are designed to assist the installation engineer with the installation ofDUPLEX boilers. The guidance given in this manual should be carefully followed to ensure

correct operation of boiler. Specific attention must be paid to :* The system design.* System water quality and water treatments.* The flue system.* The gas supply.* The electrical connections.* Regular maintenance.

1.2 FIRST FIRINGIt is recommended that the first firing of a DUPLEX boiler be carried out by the supplier ora suppliers approved engineer.

1.3 USE AND MAINTENANCEThe installer should instruct the user on correct operation and advise on the importance ofregular maintenance.

SECTION TWOSTANDARDS

The installation of the DUPLEX boiler must be carried out by a competent engineer inaccordance with the relevant requirements of the Gas Safety (Installation & Use)


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Regulations 1996, Health & Safety Executive Regulation PM5, Act, Building and IEERegulations, Local Authority, Local Gas Undertaking, Local & National Water Authority,Fire Authority, Regulations and Insurance Company Requirements.

The following British Standards/Codes of Practice are applicable :

BS 6644 Installation of gas fired hot water boilers of rated input between 60 kW and 2 MW(2nd and 3rd family gases)

BS 6880 Code of Practise for low temperature hot water heating systems of output greaterthan 45 kW

CP341.300-307 Central Heating by low pressure hot water.

CP 342 Part 2. Centralised hot water supply.

CIBSE Guide Reference Sections B7, B11 and B13

IGE/UP/2 Gas installation pipework, boosters and compressors on industrial and commercialpremises.

The efficient life of a boiler is directly relative to correct operating conditions beingachieved and maintained. The installation and maintenance of the boiler must be carriedout strictly in accordance with the instructions contained in this manual.

The manufacturers guarantee will not apply if :* the instructions for installation and maintenance are not followed strictly.* the boiler is used incorrectly.

* the boiler is not protected from corrosion, thermal shock, over pressure and lack ofwateror water flow.

2.1 CERTIFICATES

DUPLEX MODEL 220 290 360 430 500

GAS BOILERS DIRECTIVE90/396/EEC

49AO131

49AO129

49AO131

49AO131

49AO130

EFFICIENCY BOILERSDIRECTIVE

92/42/EEC

49AR001R

CLEAN COMBUSTION GASKEUR G96/027


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SECTION THREEGENERAL REQUIREMENTS

3.1 REQUIREMENTS SUMMARY

CONCEPT DETAIL VALUE

pH between 8,5 and 10

Total hardness (TH) lower than 60 ppm

Turbidity (MES) lower than 10 mg/l

Iron (mg/l) lower than 1 mg/l

Oxygen (mg/l) lower than 0,1 mg/l

Resistivity greater than 2,000 Ohm / cm

WATERPARAMETERS

Conductivity lower than 500 S/cm

Maximum FlowTemperature

90 0COPERATING WATERTEMPERATURES

Minimun returnTemperature

55 0C

OPERATING PRESSURE Maximum 4.85 bar

POWER SUPPLY 220/240 V, 50 Hz, AC and earthed

Chimney Draught

(when cold)

0 mm.w.c.

Flue Temperature, LowFire

Near 900CFLUE SYSTEM

Flue Temperature, HighFire

Near 1200C

3.2 SCALING AND CORROSION

In order to avoid scaling and corrosion :* Attention must be paid to the type of water supplied.* Frequent draining and refilling of the water of the system should be avoided.* The installation of a water meter in the filling section of the primary circuit is highly

recommended, and should be regularly checked.

PRE-TREATMENT OF THE WATER SUPPLY FOR THE PRIMARY CIRCUIT ISABSOLUTELY ESSENTIAL IN THE FOLLOWING TYPES OF INSTALLATION

* In very large installations.* Where there is frequent introduction of new water into the system.* When there are repeated partial or total draining of the system.


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3.2.1 Old installations

Before replacing boilers of an old installation by new boilers, must be proceed by:

Removal of sludge and debris from circulating water of heating system, by means:

* Clean of the installation primary circuit (if a chemical product is used it must becompatible with the installation materials). The drain must be done through aposition lower than the boiler (and not through the new boilers).

* Removing and filtering equipments for trapping particles.

* Install a water treatment and a water meter in the inflow section of the primary circuit.

Instead of the above actions, in order to avoid that the system sludge, debris magnetitesludge affect the new boilers, the boiler must be separated from the old parts of thesystem by means of a plate heat exchanger (see drawings included).

3.2.2 New installation

Cleaning of oils, welding particles, sand...A water quality control must be done in order to check if it has the proper values.

3.3 THERMAL SHOCK

The exit/flow temperature of the water in the boiler must never under any circumstancesexceed 90

0C. The return temperature must always be greater than 55

oC

3.4 WORKING PRESSURE

The maximum pressure permitted during boiler operation is 4.85 bar. This is indicated onthe boiler name-plate and must be never exceeded under any circumstances. Precautionsmust be taken against this ocurring even through accident. Ensuring conformity within thesystem is the responsability of the fitter.

3.5 FLUE SYSTEM

Detailed recommendations for the flue are given in BS6644 and British Gas IM/11.The necessary chimney diameter can be calculated as a function of the height, material,number of bends, horizontal lenght. The chimney draught (when cold) must be 0 mm.w.c.


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3.6 VENTING

All necessary precautions must be taken to avoid :* Residual deposits in the lower part of the boiler. It is advisable to incorporate a 1.6 mm

2

strainer in the return pipe.

* Air accumulation in the upper part of the boiler. Three manual release points are locatedin the upper water chamber of the boiler to perform the venting operation


The installer is required to advise the user that :

* Prior to or immediately after start-up, it is absolutely essential to carry out a cleaning

and flushing operation on the system and top-up the water treatment.

* it is recommended to avoid draining the system.

In the case of systems which utilise anti-freeze and/or additives, these must be of a typecompatible with the materials which comprise the boiler and system, so as to avoid :* chemical corrosion* galvanic action* mechanical wear* changes in viscosity


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SECTION FOURDESCRIPTION

4.1 SECTION AND PLAN ELEVATION OF DUPLEX BOILER4.1.1 DUPLEX BOILER models DUPLEX-290,360


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4.1.2 DUPLEX BOILER models DUPLEX-430, 500

The model DUPLEX-500 has a horizontal flue outlet (instead of vertical as for the othermodels), the outlet is in the right side of the boiler (seen the boiler from the control panel).


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4.2 HEAT EXCHANGER

The DUPLEX boiler heat exchanger consists of multiple vertical water tubes, laser weldedto upper and lower water collectors, and is fabricated from E24/2 and 30/10 carbon steel.

The combustion chamber is located in the centre of the water tubes creating a totallywater cooled chamber to ensure low boiler house floor temperatures.

The number of the tubes which comprise the heat exchanger depends on the power of theboiler.

The heat exchanger is silicone encapsulated, and is further insulated with foil backedmineral fibre wool, which maintains operational and standby losses at less than 1% ofoutput.

In the manufactering process three checking tests are made : verifying liquids, airpressure, water pressure.

1. Upper water collector2. Lower water collector3. Tubes of the heat exchanger4. Tubes of combustion chamber5. Combustion chamber6. Burner7. Flue collector8. Fan motor9. Water return

10. Water flow

11. Flame12. Flue (burnt gases)13. Flange to fit chimney14. Boiler casing


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4.3 BURNER

4.3.1 Kit pilot burner and control flame

The kit has the following parts :- Rectification electrode- Ignition electrode- pilot burner

Ignition is provided by fully automatic HTspark to an intermittent atmospheric pilotburner. Flame proving is via a rectificationsystem. This detects initially the presenceof the pilot flame, and then establishes

that the main burner flame is alight. Oncethe main burner flame is stable, the pilotflame is shut off.

The pilot burner has only one gas injector

4.3.2 Main burner

The main burner :A. Gas collectorB. Threaded brass injectorsC. Ignition electrode

D. Rectification electrodeE. Pilot BurnerF. Burner line assemblyG. Elbow for pilot burnerH. Air damper motorI. Pilot burner adjusting combustion

Burner lines - number depending on thepower of the boiler. The useful potential ofeach line is 68 kW.

Due to the design of the burner :- The flame is distributed all alongthe surface of the main burner.- The mix air-gas inside the burneris cooling the burner.

MODEL U. 220 290 360 430 500

Burner Lines # 3 4 5 6 7Main Burner

Gas Jets # 24 32 40 48 56


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4.4 GAS CONNECTION

Listed below are the components of the natural gas train included in the DUPLEX boilers.

For Propane gas (LPG) the parts (1) and (2) are not included.

(1) Boiler gas governor (8) Hole plate for the air damper(2) Gas governor knob (9) Threaded arm link(3) DUNGS multiblock gas valve (10) Air damper(4) Multiblock gas valve knob (11) Air collector (air damper casing)(5) Electrical connections (12) Minimum gas pressure switch(6) Gas butterfly valve (13) Maximum gas pressure switch(7) Gas collector (14) Pilot burner valve

(15) Gas flow fine adjust screw


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The diameter of the gas supply pipe to individual boilers will vary according to the power of theboiler and the type of gas used.

Gas connection diameterDUPLEX model Heat OutputkW

Natural Gas Propane Gas

DUPLEX-220 204 1 1/4" 1"

DUPLEX-290 275 1 1/2" 1 1/4"

DUPLEX-360 340 1 1/2" 1 1/4"

DUPLEX-430 408 1 1/2" 1 1/4"

DUPLEX-500 472 2" 1 1/4"

Natural Gas, G20 (20 mbar); Low calorific value (at 150

C and 1013 mbar)= 34.02 MJ/m3

Propane Gas, G31 (37 mbar); Low calorific value (at 15

0C and 1013 mbar)= 88 MJ/m

3

4.5 CONTROL PANEL

Each Duplex boiler is supplied with a factory fitted and fully tested control panel whichcomprises:- double pole isolator, burner flame safeguard control box with illuminated lockoutreset button, control thermostat, manual reset high limit safety thermostat, revolving drum typeflow and return thermometers, hours run counter and high fire delay timer. Also provided arestatus indicator lamps to indicate burner enabled, burner firing, low gas inlet pressure and water

overheat trip.

4.6 BOILER FLUEWAY SYSTEM

The entrance of the air is placed at the back of the boiler, (A). In the Air Damper Casing, (B),the air is mixed with the gas. The mix burns in the main burner (C).The burnt gases, due to the negative pressure created by the motor-fan (H,G,F), go


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through the tubes of the heat exchanger, and are collected in the Flue Collector (D), and aredriven to the chimney fitting flange (K). Then, the natural draught of the chimney mustevacuate the burnt gases.

The flueway system consist of :

(A) New air entrance(B) Air damper(C) Combustion chamber(D) Flue Collector(E) Flue damper(F) Turbine casing(G) Turbine(H) Motor

(I) Electrical condensor(J) Chimney fitting flange(K) Burnt gases Output

4.7 POSITION OF THE VARIOUSCOMPONENTS

Diagram To Follow


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4.8 TECHNICAL DETAILS

MODEL U. 220 290 360 430 500

kW 122 165 208 245 283

Low Fire Btu/h. 417,628 563,000 709,700 836,000 965,600

kW 204 275 340 408 472

Heat Outputto Water

High FireBtu/h. 696,048 938,300 1,160,080 1,392,096 1,610,464

kW 242.8 327.4 404.8 485.7 561.9Heat Input

Gross High FireBtu/h. 828,433 1,117,000

1,381,000 1,657,200 1,917,200

Flow temperature Max. 0C 90 90 90 90 90

Return temperature Min. 0C 55 55 55 55 55

liters 61 72 88 91 98Water content

UK Gal

13.41 15.83 19.35 20 21.55

Min. T=80C l/sec 6.07 8.18 10.11 12.14 14.04Water FlowRate

Max T=120C l/sec 4.04 5.45 6.74 8.09 9.36Maximum Bar 4.85 4.85 4.85 4.85 4.85Operating

PressureMin. Bar 1 1 1 1 1

m3/h 22.78 30.63 37.79 45.27 52.31Natural Gas Input Rate

ft

3

/h 804.3 1081.4 1334.2 1598.3 1846.9Nominal mbar 20 20 20 20 20Natural Gas

Inlet GasPressure Min. - Max. mbar 17 - 25 17 - 25 17 - 25 17 - 25 17 - 25

Volume (hot) m3/h 341 462 566 676 785Approx. FlueNatural Gas

Temperature 0C 121 121 121 121 121

Gas connection size (N.G.) BSP-F 1 1/4" 1 1/2" 1 1/2" 1 1/2" 2"

Flow/Return Connection BSP-M

2 1/2" 2 1/2" 2 1/2" 2 1/2" 2 1/2"

Flue connection flange Diam. mm 250 300 300 300 350

Flue system draught at boiler mbar 0 0 0 0 0

Load W 400 600 600 600 750Electrical

Supply V 220 / 240V, 50 Hz, Single Phase, earthed

kg 205 250 300 320 350Weight Empty

lbs 451 551 661 705 771

kg 266 322 388 411 448Weight Full

lbs 585 709 855 906 987Lower Calorific Value NATURAL GAS, G20 (15

0C, 1013 mbar) = 34,02 MJ/m

3


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4.9 DIMENSIONAL DATA

MODEL 220 290 360 430 500

A 522 522 669 669 669B 520 520 715 715 715

C 490 535 450 470 560

D (Flue, Chimney flange) 250 300 300 300 350

E 152 152 180 180 180

F 180 180 230 260 220

G (Water connections) 2 1/2" 2 1/2" 2 1/2" 2 1/2" 2 1/2"

Natural Gas 1 1/4" 1 1/2" 1 1/2" 1 1/2" 2"H(Gas connection)

Propane Gas 1" 1 1/4" 1 1/4" 1 1/4" 1 1/4"

I 410 410 410 410 455

J 159 169 169 169 184

K 152 192 192 192 215

L 402 402 477 477 196

M 110 110 183 183 473

N 36 75 15 33 72

P 180 222 162 186 245


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4.10 ELECTRICAL DETAILS4.10.1 SATRONIC control system

Circuit diagram and illustration of mode of operation

HS Main SwitchGW1 Min. Gas pressure switchGW2 Max. Gas pressure switchST Safety Limit ThermostatRT Control thermostatIS IonizerZ Ignition transformerM Motor fanV1 Safety electro-valveV2 Main burner electro-valvePV Pilot gas valveLW Air Pressure Switch

SA Burner lockout signal

tw Start-up timetv1 Pre-ventilation timetvz Pre-ignition timets1 Safety time ionisation pilot burnerts2 Safety time ionisation burnerstv2 Delay time for high fire

Circuit Diagram :

On one side of the control unit there is a multi-coloured disk which shows, at all times, the

point reached in the operating cycle of the boiler. This disk, in conjunction with the controlpanel indicators, allows us to define at what stage the operating cycle a fault has arisen, andlocate the origin of the fault.


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4.10.2 Electrical wiring diagram for DUPLEX boiler, models 220-290-360-430


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4.10.3 Electrical wiring diagram for DUPLEX boiler, model 500


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4.11 MANUFACTURING BOILER LABEL


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SECTION FIVEINSTALLATION

5.1 THE BOILER ROOM

The boiler room must be clean , well ventilated, well lit and constructed in accordance withthe requirements of BS6644. The safety standard of the room must satisfy the conditions setout in BS5588:Part 1. Above all, this room must not serve as a storage area. All componentsof the boiler must be accessible, to permit the necessary maintenance operations.

5.2 AIR SUPPLY & VENTILATION

An adequate supply of fresh air for combustion and ventilation of the boilerhouse must be

supplied in accordance with BS6644.

The air supply should be achieved using :a) Natural ventilation with low level and high level openings.b) Using a fan to supply air to a low level opening with natural discharge through a high levelopening.c) Using a fan to supply air to a low level opening and a fan to extract air at a high levelopening.

5.2.1 Air supply by natural ventilationWhere natural ventilation is used, suitable permanent openings, at high level and at low level,

connected directly to the outside air must be provided. Where communications with theoutside air is possible only by means of high level air vents ducting down to floor level for thelower vent(s) should be used. For an exposed boilerhouse, air vents should be fitted,preferably on all four sides, but at least on two sides.

The openings should have negligible resistance and must not be sited in any position wherethey are likely to be easily blocked or flooded or in any position adjacent to an extractionsystem which is carrying inflammable vapour. Grilles should be so designed that high velocityair streams do not occur within the space housing the boilers.

The total minimum free area requirements of the air vents should be as follows (boilersinstallations up to 2 MW), (these requirements are related to the maximum rated heat input ofthe boiler(s) and are equivalent to those specified in BS6644) :

Position of air vent Free areas (air direct from outside)

High level (outlet) 270cm2

plus 2.25cm2

per kW in excess of 60 kW of total rated input

Low Level (inlet) 540cm2

plus 4.5cm2

per kW in excess of 60 kW of total rated input


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The actual minimum effective areas of the air vents required are as follows :

Free Area of Vent per boiler model (air direct from outside)

Air Vent Uts. Duplex-220 Duplex-290 Duplex-360 Duplex-430 Duplex-500

cm2/boiler 681.5 872 1046 1228 1399.5High

in2/boiler 106 135.5 162.5 190.5 217

cm2/boiler 1363 1744 2092 2456 2799Low

in2/boiler 212 271 325 381 434

5.2.2 Air Supply by mechanical ventilation

Mechanical ventilation systems serving the area containing the boiler should be designedwith an extraction air rate of 0.45 m3/sec per 1000 kW total rated input, and an inlet air rate of1.1 m

3/sec per 1000 kW total rated heat input.

Systems employing an extract fan only must not be used, whereas the use of a single inletfan, or an inlet together with an extract fan, is acceptable.

All air inlet and extract fans should be electrically interlocked to cause safety shut-down orlock-out of the boiler in the event of malfunction of either fan.

The requirements of mechanical ventilation schemes is fully outlined in BS6644.

The following table gives the minimum mechanical ventilation rates of the DUPLEX range ofboilers :

AIR Uts. Duplex-220 Duplex-290 Duplex-360 Duplex-430 Duplex-500

Inlet(combustion,ventilation)

m3

/s 0.267 0.36 0.445 0.534 0.618

Extract(ventilation)

m3/s .0133 0.18 0.222 0.267 0.309


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5.3 BOILER BASE

Duplex boilers/modules should be installed on a level fire-proof plinth with a minimum heightof 50mm. The plinth must be capable of supporting the weight of the boilers/modules whenthey are filled with water.

5.4 MODULAR CONNECTION

Where the required boiler output exceeds the output of a single boiler, a multiple or modulararrangement of DUPLEX boilers should be considered.

All DUPLEX boilers should be installed in accordance with the relevant requirements of theBuilding Regulations, Health and Safety Executive Regulation PM5, IEE Regulation and theByelaws of the local authority and local water company.

CODES OF PRACTICE

CP341.300-307 Central Heating by low pressure hot water.CP342 Part 2. Centralised hot water supplyCIBSE Guide Reference Sections B7, B11 and B13

BS6644 Installation of gas fired hot water boilers rated inputs above 60 kW butnot greater than 2 MW.

IG/UP/2 Gas installation pipework, boosters and compressors on industrial andcommercial premises.

5.5 ELECTRICAL CONNECTION

The electrical installation must comply with the current edition of the IEE Regulations.The supply voltage must be 220/240 V, ac, 50 Hz, single phase, earthed.Electrical loading : Boiler model 220 = 400 W

Boiler model 290, 360, 430 = 600 WBoiler model 500 = 750 W

The boiler must be earthed.Electrical connections are made to the main terminal rail in the boiler control panel.The connections should be as follows :

- Supply live to terminal 2- Supply neutral to terminal 1- External controls require to be volt free switched- Low fire (stage 1) terminals 3 and 4- High fire (stage 2) terminals 5 and 6


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5.6 MOUNTING THE BOILER

The dimensions and weight of the DUPLEX boilers generally do not restrict the sittingposition. The minimum clearances detailed below should be observed.


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5.7 SYSTEM WATER

The DUPLEX boiler has a very high coefficient of heat transfer and, like all boilers of its type,

has a strict requirement for certain system design considerations as well as waterquality/system waterside cleanliness. The following points MUST be observed :

a. The DUPLEX boiler must only be installed into a sealed and pressurised system.Open vented systems are not suitable.

b. Systems must be thoroughly cleansed before connecting the boiler.

c. Where the entire system into which the boiler is to be installed is new, the water qualitymust be in accordance with the requirements listed below.

d. Where the boiler is to be retrofitted into an existing system, (a very aged heatingsystem where damaging system sludge, debris, magnetite sludge may be often befound in large quantities in an old system) the boiler must be separated from the oldparts of the system by a plate exchanger to avoid the appliance from beingcontaminated and damaged by ferric oxide sludge that will be present in the oldsystem.

Where a new DUPLEX boiler is installed in conjunction with a plate heatexchanger, the water in the primary (boiler) side of the plate heat exchangerneed only be treated with a good quality corrosion inhibitor. In addition, as theprimary system will be confined to just the plantroom, automatic makeup is not

considered necessary.

e. No guarantee will be allowed on the boiler unless the above requirements (asappropiate installation are STRICTLY observed.

5.7.1 Cleansing of old systems

Before installing any new boiler, a thorough cleansing of an old system is required to removesludge and silt, ... The chemicals used must be compatible with the materials used in thesystem.

5.7.2 Cleansing of new systems

New systems must be cleaned of all solid debris, traces of oil, flux residues, dirt, etc.


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5.7.3 Water quality

The listed water quality requirements must be observed when the entire water content of thesystem is available to the boiler. Please note however, it is always good practise to water

treat all systems.

CONCEPT DETAIL VALUE

pH between 8,5 and 10

Total hardness (TH) lower than 60ppm

Turbidity (MES) lower than 10 mg/l

Iron (mg/l) lower than 1 mg/l

Resistivity greater than 2.000 Ohm x cm

WATERPARAMETERS

Conductivity lower than 500 S/cm

5.8 WATER FLOW RATE AND TEMPERATURE RISE

The DUPLEX boiler is designed to operate with a T of between 8 - 12 0C. Pumps should beselected to overcome the boiler index circuit to provide a flow rate to achieve a T within therequired parameters outlined above.

5.9 OPERATING WATER TEMPERATURES

Maximum Flow Temperature 90

0

COPERATING WATERTEMPERATURESMinimun Return Temperature 55 0C

The DUPLEX boiler, in keeping with any carbon steel boiler must be protected from operationat low return temperatures. Measures must be taken to prevent the return temperature fromremaining below 55

0C.

5.10 BOILER HYDRAULIC RESISTANCEThe design of the boiler allows for very low pressure loss versus the power of the boiler andits physical size. The hydraulic pressure loss for a specific boiler can be found by reference to

the graph below.Volume flow (Q) (m3/h) can be determined :

Boiler Power (kW) x 0.86Q= -------------------------------------

Design boilerT

Maximum boilerT = 120C

Minimum boilerT = 80C


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5.11 HYDRAULIC CONNECTIONS

When fitting, the need for the following should be borne in mind :- Valves in the outflow and return pipes of each boiler. These valves allow the isolation

of the boiler and remove the need to drain the entire system in the event of animportant maintenance operation being required.

- A safety valve between the boiler and the outflow valve and a drainage pipe betweenthe boiler and the return valve.

- A mechanism to establish a minimum pressure in the system.- An air venting or purger installed in the outflow pipe. This become absolutely

imperative when the boiler is installed in the higher parts of a building.- An appropiate expansion system.- A drainable inertial tank depending on the volume of water and the power.

5.11.1 Inertial tank

The DUPLEX boiler should always be installed in conjunction with an inertial tank unless thewhole installation is :

a. Constant temperature - constant flow, orb. The system includes a constant temperature - constant flow circuit that is

always in operation.The inertial tank or both systems listed above (a,b) must have a water capacity equal to orgreater than that given by the following formula :

Capacity (litres) = ( Boiler Power Output x 0.774 ) - ( Boiler Water Content(litres))

Boiler Duplex-220 Duplex-290 Duplex-360 Duplex-430 Duplex-500

Min. Inertial volume(litres)

97 141 175 225 267

5.12 SYSTEM SCHEMATICS

LIST OF EQUIPMENTS 5.12.1 Typical single boiler installation1. DUPLEX boiler2. Non return valve

3. Boiler circulation pump4. Strainer5. Expansion Vessel6. Safety valve and pressure meter7. Inertial tank8. Boilers regulation9. Air venting10. Mixing valve (Weather compensated variabletemperature)11. Primary pump


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5.12.2 Typical installation of a single boiler forDHW production or a very old system

12. Three ways valve for control the flow temperature of

domestic hotwater service13. Plate heat exchanger14. Dosing point15. DHWS secondary pump16. DHWS storage vessel17. Thermostat pumps18. Pressure relief valve19. Three was valve for control the flow temperature of theDHW to secondary20. Return temperature thermostat21. Secondary recirculation pump22. Non vibration flange23. Flow swith24. DHWS recirculation pump

25. Heating system pump26. Magnetic filter27. Magnetic filter pump 5.12.3 Typical multipleinstallation (heating, DHW)28. Water meter

5.12.4 Typical multiple installation, for DHW production, or avery old system, or a heating system operating at lowtemperatures

29. Chemical product dosifier

30. Water softener31. Air venting32. Adjudting water flow valve33. Pressure switch34. Pressure meter35. Temperature meterA. HEATING FLOWB. HEATING RETURNC. COLD FEEDD. DRAINE. DOMESTIC SANITARY WATER FLOWF. DOMESTIC SANITARY WATER RETURN


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5.13 GAS SUPPLY

The gas installation should be installed in accordance with the guidance given in IGE/UP/2

and British Gas Publication IM/16.Each boiler must be equipped with an inlet isolation valve and a union or flange between theisolation valve and the boiler that allow disconnection of the boiler. Do not use pipes smallerthan the size of the boiler gas connection.

It is important to ensure that the supply of gas is adequate for the power of the boiler(s) andthat the inlet working pressure of the natural gas must be maintained within the limitsdetailed below :

minimum = 17 mbar, maximum =25 mbar, nominal = 20 mbar

The availability of an adequate gas supply or the suitability of an existing supply/meteringequipment should be established by reference to the local gas undertaking before installation.

5.14 FLUE SYSTEM

Detailed recommendations for the flue are given in BS6644 and British Gas IM/11. The areaof the flue must not be less than the area of the boiler flue outlet. Flue components should bewatertight. The flue systems must be designed to induce a zero draught at the boiler flueconnection when cold.

When installing multiple DUPLEX boilers to a common flue header, the header should incline

by 3-5% towards the main chimney.

The fitting flange between the boiler and chimney are :

Boiler model Duplex-220 Duplex-290 Duplex-360 Duplex-430 Duplex-500

Boiler flue diameter mm 250 300 300 300 350

Flue pipes and fittings should be constructed from stainless steel or acid resistant vitreousenamel lined cast iron. Chimneys should be lined with non-porous acid resistant material inaccordance with BS5854, such as stainless steel flexible flue liner or similar. The internal

diameter of the liner must not be less than the recommended flue pipe, and the number ofjoints should be kept to a minimum. Any joints between the flexible liner and the flue pipefrom the boiler should be effected by means of a purpose adapter plate. Existing flues shouldbe thoroughly swept before use and any register plates, restrictor plates or dampers shouldbe removed.

The flue outlet should be fitted with a wire mesh to protect against blockage. The terminalshould not be sited adjacent to any opening window, air vent or other ventilation opening, andshould be situated at least one metre above the roof surface. All should be in accordancewith BS6644.


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5.14.1 Possible flue connection for boiler model DUPLEX-220 to DUPLEX-430

a. An elbow adaptor may be fitted for connecting the boilers to the flue system.

Boiler 220 290 to 430

r (mm) 90 90

D (mm) 250 300

H (mm) 340 390

b. Flue outlet may be rotated, 45 or 90, as the drawingsattached, to provide discharge to either right and left.

5.14.2 Flue Outlet model DUPLEX-500

The flue connection on the model 500 is horizontal - side facing. This boiler model should befitted to the main chimney as shown in the drawing attached. When installing two DUPLEXmodel 500 together, you should order one boiler with theleft hand flue outlet and another with the right handdischarge as viewed from the front of the boiler.


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SECTION SIXSTART UP AND CONTROL

6.1 PRE-START CHECKS

The first start-up operation is a critical operation on which the future effectiveness andreliability of the system can depend. For this reason, the supplier or an approved engineermust carry out the operation.

Before start-up, it must be ensured that :

- The boiler has been installed in accordance with the manufacturers instructions.- The system is full of water and vented of air.- The static pressure in the system is between one and three bars.

- The valves are open- The water circulation pump(s) function correctly.- The gas pressure conforms with that indicated on the boiler identification plate.- The gas supply is on and purged of air.- There are no gas leaks in the system.- The electrical connections are correct (L,N, voltage 220/240 V, 50 Hz, earthed)- Power supply is available.- The controls are set so as to require heat from the system.- The minimum gas pressure switch is set to 10 mbar (natural gas).- The maximum gas pressure switch is set to 25 mbar.- The air pressure switch is set within the range 0.6 - 1.2 mbar

6.2 MEASURE INSTRUMENTS

To adjust the boiler settings various instruments are required :

- A manometer to check the pressure drop in the combustion chamber.- A manometer to check the gas burner pressure.- A manometer to check the inlet working pressure of the gas supply.- A flue gas analyser to measure CO, CO2, O2 and NOx.- Thermometers to measure the water and flue gas temperatures.

6.3. PREVIOUS CHECKINGS ON THE BOILER

a. PILOT ASSEMBLYb. AIR DAMPER MOTORc. LOW-HIGH DELAY TIMERd. FLUE DAMPER


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6.4 ADJUSTING PILOT BURNER

6.4.1 Checking the pilot burner

* The pilot assembly should be removed and the ignition electrode adjusted to 2mmfrom the inside surface of the pilot burner and 1 mm from the base of the burner (asshown in previously supplied drawings).

* The ionisation electrode should be adjusted to travel away from the burner to enablethe 200mm long pilot flame to encase the probe whilst it is being pulled by thecombustion fan.

* The return set of the ionisation probe should be placed a significant distance away

from the pilot burner, 5cm, to prevent spark migration to the probe, assisted by the airmovement created by the combustion fan.

* The updated pilot burner has 11-12 holes (diameter 3mm each one) in place of the22-23 small or 4 large holes.

* The electrodes should be inspected for cracking of the ceramic where they passthrough the retaining nuts.

* When you fit the pilot burner into the boiler, you must be sure that no extra airentrance should be between the joints. In order to avoid it, you may put some sealing

(in example, silicon) to the base.

6.4.2 Checking the combustion of pilot burner

6.4.2.1 Switch on the boiler

6.4.2.2 Place the boiler thermostat at high value.

6.4.2.3 If boiler lockout is produced, reset the boiler again.

6.4.2.4 The pilot burner will fire, a strong and blue flame must involve totally therectification probe with no lockout.

6.4.2.5 Adjust the combustion of the pilot burner :

* Rectification current of the pilot assembly must be greater than 6 micro Ampers.* The earth wire ( which creates the circuit for the rectification current) should beattached directly to the pilot assembly securing bolt.


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* Adjustment on the primary aeration ring (see drawing, Nr. J) on the pilotassembly will modify the micro Amper

reading. If the ring go down the air flowwill increase, if the ring go up the air flowwill decrease.

* The rectification reading can be takenwith a higher degree of accuracy if thesupply to the second solenoid within theDungs gas valve is interrupted :

- This is achieved by dismantlingthe multi-wire connector that plugs

into the DUNGS valve anddisconnecting the brown wire Nr. 3

- The unit will pass to lockout oncethe unit tries to establish low fire.

- Re-connect and plug the multi-wire connector into the DUNGSvalve.


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6.5 PRIMARY AIR DAMPER MOTOR

The damper motor is preset, however if a new unit is supplied and the old unit is not

available, the initial settings should be as follows :

* When the damper is in the high fire position the injectors in the gas manifold shouldbe in view, but not the gas manifold. When viewed from directly above the assembly.

When the damper is in this position the link to the gas butterfly valve should bring thegas butterfly to the horizontal (fully open).

* For natural gas : the linkage between the damper and the gas butterfly valve shouldbe set with the ball and socket bolt on the air damper in the second from the end hole,and the gas butterfly valve third from the end.

* For LPG : the linkage between the damper and the gas butterfly valve should be setwith the ball and socket bolt on the air damper in the second from the end hole, andthe gas butterfly valve third from the end.

* When the damper is in the low fire position it should have a gap of between 5-8 mmfrom the blade to the damper housing.

* This setting is intended as a guide and fine adjustments can be made once the unit isoperating.

6.6 LOW - HIGH FIRE DELAY TIMER

The low to high fire delay timer is set at the factory to 2 minutes. However this is foundto be short for the U.K. climate, a setting between 4 to 7 minutes would be suitable.

6.7 FLUE DAMPER

The flue damper position is preset from factory. It is not usual to modify it. See explanation at6.8.7a. It is function of the boiler size or model and the chimney. ( see 6.8.7a), Once this isadjusted for the draught, no more adjustings should be necessary during the operational lifeof the boiler.

6.8 ADJUSTMENT OF SECOND STAGE (HIGH FIRE)

6.8.1 Link boilers terminals 3 and 4

6.8.2 Link boilers terminals 5 and 6

6.8.3 Turn on the power supply and set the control thermostat to a high setting


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6.8.4 After a delay, the burner will function at high fire.

If the unit fails to operate from pilot to low fire, adjust the threaded linkage between the

air damper and the gas butterfly valve to increase the through put at low fire.

Once high fire has been achieved the unit should be allowed to operate until the waterflow temperature is is within 5

0C of the final working temperature.

6.8.5 Be sure the gas butterfly valve is at maximum opening (horizontal)

6.8.6 Ensure the throughput control on the DUNGS multiblock gas valve is set to maximumopening.

* Knob Nr. 4 (see drawing on Page Nr. 15) placed at maximum opening.* knob Nr. 15, max. opening ( Anticlockwise).

6.8.7a If a dedicated gas meter is not available the following steps must be taken

* Use the Factory Settings Combustion Check List (every boiler is delivered with hisown Checking List from the factory) Attached to the inside of one of the top sidepanels.

* Verify the combustion chamber pressure (negative value) is near the setting fromfactory check list. Tolerance +/- 15%.

If pressure is too far from setting, adjust the flue damper (placed at back of the

boiler).

If pressure is more negative --> close the flue damper.If pressure is less negative --> open the flue damper.

Once the damper has been adjusted, the locking nut should be tightened. Noadditional or future adjustments should be done to the flue damper.

* Check the manifold gas pressure (high fire) is near the setting from factory.Tolerances : +/- 15% from factory setting.

Adjust : burner pressure and combustion settings (CO2= 7.7 to 7.9%, for NaturalGas), by regulating the boiler gas governor at the rear of the unit, fluereadings must be taken via the flue gas analyser.

* If you adjust the combustion settings :

- with the casing off, the CO2 will increase by approximately 0.2% when thecasing is fitted.

- While boiler is working at a lower temperature than 700

C, the CO2 willincrease when the boiler gets hotter.


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-

6.8.7b If a dedicated gas meter is available the following steps must be taken

* Adjust gas flow and combustion settings (CO2= 7.7 to 7.9%, for Natural Gas), byregulating the boiler gas governor at the rear of the unit, flue readings must betaken via the flue gas analyser.

- with the casing off, the CO2 will increase by approximately 0.2% when thecasing is fitted.

- while boiler is working at a lower temperature than 700C, the CO2 will increasewhen the boiler gets hotter.

6.8.8 Once the unit is within 50C of the required flow temperature an accurate check can be

made.

6.9. ADJUSTMENT OF FIRST STAGE (LOW FIRE)

6.9.1 Turn off power supply and remove link between terminals 5 and 6.

6.9.2 Turn on power supply and the boiler should fire at low fire.

6.9.3 The adjustment for low fire is undertaken via the threaded link between the primary airdamper and the gas butterfly valve.

* Unscrew the locking of the threaded link.

* Turn the threaded link in the proper sense in order to obtain the combustion settings.You are adjusting the gas flow for a fixed air flow.

On low fire, the CO2 (%) value maybe 0.2 % lower than for high fire, but inside 7.7% to7.9%.

* Once a suitable figure has been achieved the linkage should be locked with the twolocking nuts one at either end.

* Check the Gas Jets Pressure and the Combustion Chamber Pressure (bothnegatives) are near to the values of the factory settings.

6.9.4 Only if necessary : Adjust burner air damper position (only if last values checked arevery different from factory settings).>15%+

* With the boiler switched on.

* For increasing the air flow, on the air damper motor you must link between

terminals Nr. 2 and 3.


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Once the combustion readings (in the flue gas analyser) are reached (CO2 = 7.7% to7.9%), switch off the boiler.

The air damper will remain at the last position.

* Lock the minimum opening position for the air damper by means of the lockingincluded in the motor.

* Check the Gas Jets Pressure and the Combustion Chamber Pressure (bothnegative) are near to the values of the factory settings.

6.10 WARNINGS ON COMBUSTION HIGH AND LOW FIRE :

6.10.1 If the unit is allowed to run with a CO2 reading greater than 8,2% (with the

casing in place) the burner will fail due to overheating.

6.10.2 The boilers must not be operated if work is being undertaken within the vacinityof the plant that will create airbourne dust.

6.10.3 When several boilers are installed in the same boiler room, the gas dynamicpressure (when all the boilers are operating at high fire at the same time) mustbe checked. The dynamic pressure must be greater than 18 mbar.

6.10.4 Combustion adjust for L.P.G. (Propane, G31) boiler :

* The boilers supplied for burning with L.P.G. will not have a gas governor.

* The gas flow adjustment is made by means of the knobt (Nr. 15, see drawingin Page Nr. 15) of the DUNGS gas valve. Turning it in a clockwise direction willdecrease the gas pressure, anticlockwise turning will increase the gas pressure.

* Combustion figures should be CO2 between 7.7 and 7.9 % (high fire).

6.11 READINGS ON THE BOILER

Here is attached a drawing with the reading points for the several values requested foradjusting the DUPLEX boilers.

1. O2% value2. CO2% value3. CO(ppm) value4. Air excess5. Boiler efficiency (%)6. Flue temperature (

0C)

7. Flow water temperature (0C)

8. Return water temperature (0C)

9. Boiler room temperature (0C)10. Inlet Gas Pressure (mbar.)


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11. Burner Jets gas pressure (mbar.)12. Gas consumption (m

3/h)

13. Combustion chamber pressure (mbar.)14. Flue collector pressure (mbar.)15. Chimney pressure (mbar.)


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NOTE :At the end of each first start-up operation, all the readings relating to combustion figures(combustion, air pressure, operating water temperatures, ...) should be taken. See table

above :

Sample


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SECTION SEVENFAULTS DURING OPERATION

Should a fault occur, it will be necessary to contact a specialist engineer for assistance.

There are predominantly two types of fault:- those which lead to inefficient operation or combustion.- those which cause the boiler to stop working.

7.1 POOR COMBUSTION

The poor combustion does not result in the boiler not working, but reduces the efficiency andeffectiveness of the boiler. The usual indication of a problem in this area is noisy or unstablecombustion and/or a yellow colouring of the flame. The usual course of action is to re-

commission the boiler in accordance with the start-up instructions.

7.2 FAULTS THAT CAUSES THE BOILER NOT WORKING

In order to ascertain the problem area or component which causes the boiler to stop working,it is necessary to observe the point at which the boiler operating sequence stops. The boileris controlled by a Satronic flame safeguard control box. On one side of the control unit thereis a multi-coloured disk which shows, at all times, the point reached in the cycle at a giveninstant. This apparatus, in conjunction with the control panel lights, allows us to determine atwhat stage the operating cycle a fault has arisen, identifying the problem area.

7.2.1 White Sector and the boiler is not operating.

Check that :- there is a heat requirement.- the regulating thermostat electrically connected and calling for heat.- the control box, Satronic, is properly connected.

7.2.2 BLUE Sector.

The boiler has stopped due to lockout of the control box, the green lamp indicating heatdemand is lit. Check :

- the volume control damper at the inlet to the combustion fan.- the fan motor connections and the condition of the fan.- the setting of the air pressure switch.

7.2.3 RED Sector.

The boiler has stopped due to lockout of the control box, the green lamp indicating heatdemand is lit. Check :


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- the pilot burner gas supply solenoid coil.- the isolation of the ignition and rectification electrodes.- the spark gap between the ignition electrode and the pilot burner.

- the ignition transformer.- the gas pressure switch for maximum is set properly.

7.2.4 YELLOW Sector

The boiler has stopped due to lockout of the control box, the green lamp indicating heatdemand is lit, the amber lamp indicating low gas pressure is lit, the red lamp indicatinglockout is not lit. Check :

- the gas supply pressure.

- the gas valves solenoid coils.- the setting of the minimum gas pressure switch.

7.2.5 GREEN sector

The boiler has stopped. The green lamp indicating indicating heat demand is lit. Check theboiler combustion.

7.2.6 GREEN sector.

The boiler has stopped. The green lamp indicating indicating heat demand is lit, the red lampindicating overheating is lit. Check :

- the system is correctly filled, : the water pressure, water flow and the inertial volume.- the pumps are running- the calibration of the control thermostat. Note : it will be necessary to reset the safety limitthermostat with a screwdriver.


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FAULT CAUSE ACTION TO BE TAKEN

Boiler has stoppedOn-Off Switch not lit

- On-off switch is off.- No electrical supply to the boiler

- Press the On-off switch- Check the electrical supply.

Boiler has lockoutControl box lamp is lit

It does not mean a fault in the boiler.Several external factors may be the cause

- Reset the boiler- Check installation and system.

Boiler has stopped

Green lamp indicatingheat demand is not lit.

- No heat demand in the system.- Control thermostat set very low- Water pressure switch detects no pressure- Boiler pumps are stopped.- External control no acts.

- Check the system water temperature- Set the control thermostat- Check the water pressure on the boilercircuit- Check the pump- Check external controls

Begin the boiler cycleand the boiler getslockout.

- Burner is dirty- Air damper not proper set

- Air pressure switch not correct.- Motor-fan does not operate.

- Clean the burner and check.- Increase air flow- Set pressure air switch to 0.6 mbar- Check pressure- Check motor-fan

No ignition spark

Lockout light of controlbox is lit.

- Cracked ignition electrode ceramic- Gap between ignition electrode and pilotburner or earthed- Ignition transformer broken.- Control box broken

- Change ignition electrode- Set gap to 2 mm

- Change transfomer- Change control box

When carrying outnormal cycle, cuts outasap burner is lit.

- Cracked ionization electrode- Control box faulty- Gas Pressure Switch max. set too low

- Change ionization electrode- Change Control box- Set Pressure Switch Maximum

The burner fails toignite

- No gas flow- Gas flow inadequate- Excess of air

- Faulty/not supplied pilot solenoid valve- Faulty air damper motor.- Pilot burner fails to ignite- Burner in poor condition

- Check the gas valve is opened- Check gas pressure and flow- Decrease the air flow

- Check electro-valve- Change air damper motor- Check pilot burner electro-valve- Check or change burner

Abnormal noises in theboiler heat exchanger

- Air inside the water piping- Pump running so fast- Scaling on inside the boiler- Sludge inside the exchanger

- Air vent the system- Adjust pump flow- Clean with descaling product- Check water quality / system leakages- Install water treatment- Clean the heat exchanger- Clean installation + filter before boiler

No lockout of Controlbox. All lamps not lit.On-off switch lit +Control thermostat lit

- Control thermostat faulty- External boilers controls

- Check and change if required- Check, link the boilers terminals 3 & 4, tooperate the boiler.

No lockout of Controlbox. All lamps not lit.Control thermostat litRed Lamp is lit

- Control thermostat faulty- System inertial due to high temp.- Low inertial water volume in boiler- Boiler pump failure- Water valves are closed.

- Replace thermostat.- Reset boiler.- Check inertial volume.- Check mixing valves- Check boiler pump- Check boiler water valves


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SECTION EIGHTMAINTENANCE

8.1 CLEANING THE BURNER AND THE COMBUSTION CHAMBER

- You must clean the burner each 1000 hours measured in the hours run counter of theboiler, it depends also of the dust in the air of the boiler room.- Turn off the gas- Switch off the power- Remove the top and upper side casing panels- Disconnect the HT and rectification connections from the electrodes- Disconnect the wiring of the air damper motor- Separate the burner from the gas supply by removing the four screws in the flange on theoutlet of the Dungs gas valve.

- Unscrew the retaining nuts to free the burner- Dismantle all the copper piping connected to the pilot- Take out the air distributor and the burner- Separate the burning mounting from the air collector- Clean the mounting inside and out with a brush or pressurised air.- Dismantle the electrodes and check the state of the ceramic, adjusting the ignition electrodeto 2 mm of the inner part of the pilot burner, adjust the position of the rectification electrode.- Clean the combustion chamber using a brush and vacuum cleaner- Reassemble by reversing the procedure

8.2 CLEANING THE HEAT EXCHANGER

- Dismantle the casing- Remove the thermal insulation- Remove the burner- Dismount the combustion fan assembly- Clean the inside of the combustion chamber with an industrial vacuum cleaner- Clean the smoke passages with an industrial vacuum cleaner with brushes- Check soundness of combustion chamber silicone sealing, and if necessary make localrepairs.

8.3 CHECKING BOILER

- Start up the boiler system- Check the ignition spark. 2 mm separation- Check the pilot flame- Check the burner flame verifying that the combustion levels correspond to the type of gasbeing used; carry out the checks at low and high fire.


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SECTION NINELIST OF BOILERS COMPONENTS

Duplex Operating Manual

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Transcript of Duplex Operating Manual