Glow-worm Xtramax User Manual

Instructions for Use

Installation and Servicing

To be left with the user

XTRAMAX

G.C. No. 47-047-15

Unvented Hot Water Storage

Fanned Flue Combination Boiler

4000116705-2.10.02

9088

This is a Cat II

The instructions consist of three parts, User, Installation and Servicing Instructions, which include the Guarantee Registration Card.

The instructions are an integral part of the appliance and must, to comply with the current issue of the Gas Safety (Installation and Use)

Regulations, be handed to the user on completion of the installation.

Appliance

2H3+

Guarantee Registration

Thank you for installing a new Glow-worm appliance in your home.

Glow-worm appliances' are manufactured to the very highest standard so we are pleased to offer our customers' a

Comprehensive Guarantee.

This product is guaranteed for 24 months from the date of installation or 30 months from the date of manufacture, whichever

is the shorter, for parts. In addition this product is guaranteed for 12 months from the date of installation or 18 months from

the date of manufacture, whichever is shorter, for labour.

The second year of the parts guarantee, from the beginning of the 13th month onwards after installation, is conditional upon

the boiler having been serviced by a CORGI registered gas installer, in accordance with the manufacturer's

recommendations. We strongly recommend regular servicing of your gas appliance, but where the condition is not met, any

chargeable spare parts or components issued within the applicable guarantee period still benefit from a 12 month warranty

from the date of issue from the manufacturer.

We recommend you complete and return as soon as possible your guarantee registration return literature, supplied in the

document envelope.

If your guarantee registration return literature is missing you can obtain a copy by telephoning the Heatcall Customer Service

number 01773 828100.

CALL 0208 247 9857

Hepworth Heating Ltd.,

Nottingham Road, Belper, Derbyshire. DE56 1JT

General/Sales enquiries:

Tel: (01773) 824141 Fax: (01773) 820569

Contents

CONTENTS DESCRIPTION SECTION PAGE No.

Important Information 3

INSTRUCTION

FOR USE

INSTALLATION

INSTRUCTIONS

Appliance Introduction 4 Appliance Safety Devices 5 Service and Maintenance 5 Operating the Appliance 6 Xtracom Remote Control 8

Technical Data 1 9 General Information 2 10 Heating System Design 3 11 Domestic Hot Water System Design 4 12 Boiler Schematic 5 12 Boiler Location, Flue and Ventilation 6 13 Safety Discharge 7 15 Fixing Jig 8 15 Piping System Installation 9 16 Boiler Installation 10 18 Horizontal Telescopic Top Flue Installation 11 19 Horizontal Top Flue Installation 11a 20 Electrical Connection 12 22 Commissioning 13 23 Safety Devices 14 26 Changing Gas Type 15 27 Settings 16 27

SERVICING

INSTRUCTIONS

Routine Cleaning and Inspection 17 28 Fault Finding 18 31 Replacement of Parts 19 33 Wiring Diagram 20 34 Spare Parts 21 44

4000116705-2

Important Information

Gas safety (Installation and use) Regulations

In your interests and that of gas safety, it is the law that ALL gas appliances are installed and serviced by a competent person in accordance with the above regulations.

Testing and Certification

This boiler is tested and certificated for safety and performance. It is therefore important that no alteration is made to the boiler, without permission, in writing, from Hepworth Heating Ltd.

Any alteration not approved by Hepworth Heating Ltd., could invalidate the certification, boiler warranty and may also infringe the current issue of the Statutory Requirements. The requirements are: The installation of this boiler must be carried out by a competent person in accordance with the current rules in force in the countries of destination at the time of installation. Manufacture's instructions supplied. Manufacture's instructions must not be taken as overriding statutory requirements.

Mandatory WARNING for EEC countries

This appliance is designed, approved and inspected to meet the requirements of the Intended market. The data label indicates where the product was manufactured and the

country for which it is intended.

CE Mark

This boiler meets the requirements of Statutory Instrument No. 3083 The boiler (Efficiency) Regulations, and therefore is deemed to meet the requirements of Directive 92/42/EEC on the efficiency requirements for new hot water boilers fired with liquid or gaseous fuels.

Type test for purposes of Regulation 5 certified by: Notified body 0086.

Product/production certified by: Notified body 0086.

The CE mark on this appliance shows compliance with:

1. Directive 90/396/EEC on the approximation of the laws of the Member States relating to appliances burning gaseous fuels.

2. Directive 73/23/EEC on the harmonization of the Laws of the Member States relating to the electrical equipment designed for use within certain voltage limits.

3. Directive 89/336/EEC on the approximation of the Laws of the Member States relating to electromagnetic compatibility.

Control of Substances Hazardous to Health

The adhesives and sealants used in this appliance are cured and give no known hazard in this state.

INSULATION PADS/CERAMIC FIBRE

These can cause irritation to skin, eyes and the respiratory tract. If you have a history of skin complaint you may be susceptible to irritation. High dust levels are usual only if the material is broken. Normal handling should not cause discomfort, but follow normal good hygiene and wash your hands before eating, drinking or going to the lavatory. If you do suffer irritation to the eyes or severe irritation to the skin seek medical attention. The insulation is composed of non-combustible material.

Electrical Supply

WARNING: This boiler must be earthed.

All system components shall be of an approved type and shall be connected in accordance with the current issue of BS7671 and any applicable local regulations.

All external wiring between the appliance and the electrical supply and earthing requirements shall comply with the current IEE Regulations.

Connection of the boiler and system controls to the mains supply must be through a common isolator and must be fused 3A, maximum. This method of connection must be by a fused double pole isolating switch, with a minimum contact separation of 3mm on both poles. The switch should be readily accessible and preferably adjacent to the appliance. It should supply the appliance only and be easily identifiable as so doing.

Alternatively, an unswitched shuttered socket outlet and 3A fused 3 pin plug, both to the current issue of BS1363 may be used provided that they are not used in a room containing a bath or shower.

Wiring to the boiler must be PVC 85oC insulated cable, not less than 0.75mm2 (24/0.20mm).

Manual Handling Guidance

During the appliance installation it will be necessary to employ caution and assistance whilst lifting as the appliance exceeds the recommended weight for a one man lift.

In certain situations it may be required to use a mechanical handling aid.

Take care to avoid trip hazards, slippery or wet surfaces.

Spare Parts

REMEMBER, When replacing a part on this appliance, use only spare parts that you can be assured conform to the safety and performance specification that we require. Do not use reconditioned or copy parts that have not been clearly authorised by Hepworth Heating Ltd.

4000116705-2

Important Information

Heating System Controls

The heating system must be controlled as described in the relevant part of the current issue of :

Building Regulations, approved document L1, and the references:

1) GIL 59, 2000: Central heating system specification (CheSS) and

2) GPG 302, 2001: Controls for domestic central heating system and hot water. BRECSU.

3) The domestic heating and hot water guide to the building regulations 2001.

Thermostatic radiator valves may be installed, however they must not be fitted in a room where the room thermostat is located.

Gas leak or fault

If a gas leak or fault exists or is suspected, turn the boiler off and consult the local gas supply company or your installation/ service company.

Air in the heating system

Persistent air in the heating system may indicate leaks in the system or corrosion taking place. Call your Installation/Servicing company.

Draining and filling

Caution: The boiler is installed as part of a sealed system which must only be drained and filled by a competent person.

If the boiler is to be out of use for any long periods during severe weather conditions, it is recommended that the whole system, including the boiler, be drained to avoid the risk of freezing.

If in doubt, consult your servicing company.

Protection Against Freezing

The appliance has a built in frost protection programme as long as the electricity and gas are left switched on.

This device operates the burner and system pump when the temperature inside the boiler falls below 6

Any other exposed areas of the system should be protected by a separate frost thermostat.

If the mains electricity and gas are to be turned off for any long periods during severe weather, it is recommended that the whole system, including the boiler, should be drained to avoid the risk of freezing. Make sure that, if fitted, the immersion heater in the cylinder is switched off.

If you have a sealed water system contact your installation/ servicing company as draining, refilling and pressurising MUST be carried out by a competent person.

Appliance Introduction

The XTRAMAX boiler with electronic ignition providing central heating and stored hot water.

The boiler is of the II as distributed in the United Kingdom, or Butane (G30), Propane

(G31) with the appropriate conversion kit.

The boiler has a fan assisted balanced flue which both discharges the products of combustion to and draws the combustion air from the outside of the room.

The boiler is suitable for horizontal top outlet flue connection and can be fitted with horizontal flue, vertical flue or twin-pipe flue. Refer to flue options guide for further information, this is available from your nearest stockist.

Both the central heating and domestic hot water temperature are user adjustable.

Domestic hot water demand always has priority over heating demand.

The boiler is designed for use as part of a sealed water central heating system with fully pumped circulation. The pump, expansion vessel and associated safety devices are all fitted within the boiler.

The boiler can be installed against either an external wall or on an adjacent inside wall, that is, the flue system will pass directly to the rear or to either side to the terminal fitted on the outside wall face.

boiler is a wall mounted modulating combination

category for use with Natural Gas (G20)

2H3+

The installation of this boiler must be carried out by a competent person in accordance with the rules in force in the countries of destination.

Manufacturer’s instructions must not be taken as overriding statutory requirements.

These instructions should be carefully followed for the safe and economical use of your boiler.

Note: The boiler serial number is marked on the data label attached to the rear of the control box. The 'Operating the Appliance' section describes how to safely use the boiler.

Accessories

A range of accessories are available.

For further information contact your supplier.

Flue options

There are various flue systems to choose from, for detailed information refer to flue options guide, which is available from your nearest stockist.

4000116705-2

Appliance Safety Devices

Air flow rate safety device

If the flue is obstructed, even partially, the built in safety system will turn the boiler OFF, the fan will continue to run. The boiler will be ready to operate when the fault has been cleared.

Overheating safety

In the event of the boiler overheating the safety devices will cause a safety shutdown. If this happens, call your Installation/ Servicing company.

In case of power supply failure

The boiler no longer operates. As soon as power supply is restored, the boiler will be automatically restarted.

Frost protection

The appliance has a built in frost protection device that protects the boiler from freezing. With the gas and electric supplies ON and irrespective of any room thermostat setting, the frost protection device will light the boiler when the temperature of the boiler water falls below 6°C.

When the temperature reaches 16°C, the boiler stops.

Any other exposed areas of the system should be protected by a separate frost thermostat.

Heating safety valve

CAUTION: A heating safety valve with a discharge pipe is fitted

to this boiler.

The valve MUST NOT BE TOUCHED except by a qualified registered person. If the valve discharges at any time, switch the boiler off and isolate it from the electrical supply. Contact your installation/service company.

Temperature pressure/ relief valve

CAUTION: A domestic hot water pressure relief valve, with a

discharge pipe is fitted to this boiler.

Service and Maintenance

Servicing and Maintenance

To ensure the continued efficient and safe operation of the appliance it is recommended that it is checked and serviced as necessary at regular intervals. The frequency of servicing will depend upon the particular installation conditions and usage, refer to guarantee registration on the front cover of this literature.

If this appliance is installed in a rented property there is a duty of care imposed on the owner of the property by the current issue of the Gas Safety (Installation and Use) Regulations, Section 35.

Servicing/maintenance should be carried out by a competent person in accordance with the rules in force in the countries of destination.

To obtain service, please call your installer or Heatcall (Glowworm’s own service organisation) using the telephone number on the front cover of this literature.

Please be advised that the ‘Benchmark’ logbook should be completed by the installation engineer on completion of commissioning and servicing.

All CORGI Registered Installers carry a CORGI ID card, and have a registration number. Both should be recorded in your benchmark Logbook. You can check your installer is CORGI registered by calling CORGI direct on: 01256 372300.

Cleaning

WARNING: This appliance contains metal parts (components) and care should be taken when handling and cleaning with particular regard to edges of sheet metal parts to avoid any possibility of personal injury.

The boiler casing can be cleaned with a damp cloth, followed by a dry cloth to polish.

Do not use abrasive or solvent cleaners.

Boiler casing

CAUTION. Do not remove or adjust the casing in any way, as

incorrect fitting may result in faulty operation. If in doubt, consult your installation/service company.

4000116705-2

Operating the Appliance

Controls

The control panel, located at the lower front of the boiler casing, see diagram 1, allows the boiler to be started, shut down, controlled and monitored during use.

1 - On/Off button 2 - Summer/Winter mode selector 3 - Hot water temperature adjuster 4 - Hot water set point display (must be set at maximum)

mode

1.5 bar

The appliance incorporates a visual display that indicates fault conditions, should they occur.

In the event of a fault, the display will indicate, by means of pictograms and/or letters and numbers, exactly in which area the fault lies.

Should the boiler fail to operate, the most likely fault is that the gas supply to the boiler has not been turned on or that there is no pressure in the heating system. These are indicated as follows :

No gas supply

5 - Graphic display 6 - Heating temperature adjuster 7 - Heating set point display 8 - Display backlight

158 7 26 34

9084

Diagram 1

This will be indicated on the display as a pictogram of a spark. To rectify this, proceed as follows:

• Switch off the boiler at the On/Off push button.

• Rectify the gas supply problem.

• Restart the boiler by pressing the On/Off button.

Insufficient system pressure

This will be indicated on the display as a flashing warning

0.3

bar

indicating the system pressure is low. To rectify this the system must be re-filled, refer to

'Section 13 Commissioning'.

Other faults

These are indicated on the display by a fault code and a telephone symbol. Further information on the fault codes can be found in the 'Section 18 Fault Finding'.

4000116705-2

Operating the Appliance

Lighting the boiler :

Make sure that:

 The boiler is connected to the electrical supply.  The gas service cock is open.

Then follow the instructions below :

Press the On/Off button (1)

The pressure must be between 1 and 2 bar. If not, the system must be filled by a competent person.

mode

1.5 bar

To stop the boiler : Press button (1)

9087

Setting to the SUMMER position

(Hot water only)

Press the mode button to select the summer symbol

mode

1.5

bar

The flame symbol appears when the boiler is running

Adjusting the hot water temperature

The domestic hot water must be set at max 60°C. Press + or - to adjust the maximum temperature of the hot water.

Visual indication of set temperature

Setting to the WINTER position

Press the mode button to select the winter symbol

The actual temperature of the heating system

Adjusting the heating temperature

Press + or - to adjust the maximum temperature of the heating (38°C to 87°C)

(Heating + hot water)

°C

Visual indication of set temperature

1.5

bar

Illuminates when the boiler lights

mode

°C

To obtain domestic hot water, open a hot water tap. Hot water always has priority over central heating.

mode

°C

mode

4000116705-2

Hab261

Xtracom Remote Control

Xtracom programmable, roomstat and boiler remote control panel part No. A20077.

PROGRAMME/ THERMOSTAT DISPLAY

REMOTE CONTROL DISPLAY

REMOTE CONTROL OPTION

Diagram 2

Clock Timer and Thermostat Controls:

1 - Days of the week

2 - Override indicator

3 - Low Battery indicator

4 - Time display

5 - Heating in operation

6 - Programme temperature

7 - Room temperature

8 - Programme display

9 - Current programme status

10 - Override / Timed Override button

11 - OK/Enter button

12 - Plus and Minus modification buttons

13 - Manual programme setup buttons

14 - Time set button

15 - Temperature settings button

16 - Programme set button

17 - Cancel/Stand-by button

18 - Boiler Fault LED

3 4

Setting the Time

• Press button 14.

• Press + or - to set the correct hour.

• Press OK.

9091

• Press + or - to set the correct minutes.

• Press OK.

• Press + or - to set the correct day (1 = Mon. 7= Sun).

• Press OK, the clock will start.

Presetting the Temperatures T1, T2 and T3

The programmes use three temperature settings which you can adjust.

Recommended first use settings are:-

T1=16°, T2=19°, T3=21°

If the radiators in your installation are equipped with thermostatic valves, the highest temperature you can set on T3 is determined by the highest setting on the radiator thermostatic valves.

e.g. If the highest radiator thermostat valve setting is 21°C then you must set T3, 2 or 3°C higher, 24°C.

• Press button 15 T1 is displayed.

• Press + or - to set desired temperature.

• Press OK, T2 is displayed.

• Press + or - to set desired temperature.

• Press OK, T3 is displayed.

• Press + or - to set desired temperature.

• Press OK.

Weekly Programming

9328

9329

Diagram 4

9330

4000116705-2

Diagram 3

Diagram 5

There are 6 preset (P1 to P6) programmes and one manual (P=) programme which can be assigned to each day of the week (1 to 7), the Factory default setting is P3 on all days. (Programmes P1 to P6 can not be changed).

• Press button 16 to set day 1 (Monday).

• Press + or - to assign a programme to day 1.

• Press OK

1 Technical Data

Heating

Heating input adjustable from 12,5 kW

to 30,3 kW

from 42,650 BTU/H

to 103,383 BTU/H

Heating output adjustable from 10,4 kW

to 27,6 kW

from 35,484 BTU/H

to 94,170 BTU/H Efficiency 82 % Maximum heating temperature 87 °C Expansion vessel effective capacity 8 l Expansion vessel charge pressure 0,5 bar Maximum system capacity at 75°C 180 l Safety valve, maximum service pressure 3 bar Products outlet diameter 60 mm Fresh air inlet diameter 100 mm

Hot water

Heating input adjustable from 12,5 kW

to 30,3 kW

from 42,650 BTU/H

to 103,383 BTU/H

Hot water output, automatically variable from 10,4 kW

to 27,6 kW

from 35,484 BTU/H

to 94,170 BTU/H Storage capacity 43 l Maximum hot water temperature 60 °C Minimum hot water temperature 37°C Specific flow rate (for 35°C temp rise) 11,4 l/min. Threshold flow rate 1 l/min. Nominal water flow rate 11,3 l/min. Temp./pressure relief valve opening pressure 7 bar Temp./pressure relief valve opening temperature 90°C Cylinder heat up time 4 min. Time to reheat 70% of storage to 60°C5 min. Expansion valve setting 6 bar Expansion vessel charge pressure 3.5 bar Maximum operating pressure 3.5 bar Maximum supply pressure 16 bar Minimum operating pressure 0,7 bar

Natural Gas (G20)

Ø Burner injector 1,20 mm Inlet pressure 20 mbar Maxi. Burner pressure 13,8 mbar Mini. Burner pressure 2,16 mbar Gas rate maximum 3,20 m3/h Gas rate minimum 1,32 m3/h

Butane Gas (G30)

Ø Burner injector 0,77 mm Inlet pressure 29 mbar Maxi. Burner pressure 23,8 mbar Mini. Burner pressure 3,6 mbar Gas rate maximum 2,39 kg/h Gas rate minimum 0,99 kg/h

Propane Gas (G31)

Ø Burner injector 0,77 mm Inlet pressure 37 mbar Maxi. Burner pressure 30,8 mbar Mini. Burner pressure 3,6 mbar Gas rate maximum 2,35 kg/h Gas rate minimum 0,97 kg/h

The Seasonal Efficiency Domestic Boilers UK (SEDBUK) is, "D" 78.9%.

The value is used in the UK Government's Standard Assesment Procedure (SAP) for energy rating of dwellings. The test data from which it has been calculated have been certified by B.S.I.

131

234

Hab322

Weight of appliance when empty 71 kg Weight of appliance when full 110 kg

Electrical

Electrical supply 230 V Maximum absorbed power 235 W Level of protection IP44 Fuse rating 3A

WEIGHT 71 kg

The separate packages:

• The boiler

• The fixing jig

• The flue system

890

XTRAMAX

600

480

is delivered in three

Diagram 1.1

4000116705-2

2 General Information

IMPORTANT NOTICE.

Where no British Standards exists, materials and equipment should be fit for their purpose and of suitable quality and workmanship.

Refer to Manual Handling Operations, 1992 regulations.

The installation of this boiler must be carried out by a competent person in accordance with the rules in force in the countries of destination.

Manufacturer’s instructions must not be taken as overriding statutory requirements.

1.1 Sheet Metal Parts

WARNING: When installing the appliance, care should be

taken to avoid any possibility of personal injury when handling sheet metal parts.

1.2 Statutory Requirements

The installation of the boiler MUST be carried out by a competent person in accordance with the relevant requirements of the current issue of:

Manufacturer’s instructions, supplied.

The Gas Safety (Installation and Use) Regulations, The Building Regulations, The Building Standards (Scotland) Regulations (applicable in Scotland), local Water Company Bylaws, The Health and Safety at Work Act, Control of Substances Hazardous to Health, The Electricity at Work Regulations and any applicable local regulations.

Detailed recommendations are contained in the current issue of the following British Standards and Codes of Practice, BS4814, BS5440 Part 1 and 2, BS5449, BS5546, BS6700, BS6798, BS6891 and BS7074 Part 1 and 2, BS7478, BS7593, BS7671.

Manufacturer’s notes must not be taken as overriding statutory obligations.

BSI Certification

This boiler certificated to the current issue of EN 483 for performance and safety.

It is important that no alteration is made to the boiler, without permission, in writing, from Hepworth Heating Ltd.

Any alteration that is not approved by Hepworth Heating Ltd., could invalidate the warranty and could also infringe the current issue of the Statutory Requirements.

1.3 Gas Supply

The gas installation must be in accordance with the current issue of BS6891.

The supply from the governed meter must be of adequate size to provide a steady inlet working pressure of 20mbar (8in wg) at the boiler.

On completion, test the gas installation for soundness using the pressure drop method and suitable leak detection fluid, purge in accordance with the above standard.

3 Heating System Design

• The XTRAMAX is for use ONLY with sealed central heating systems.

• Heating surfaces may consist of radiators, convectors or fan assisted convectors.

• The appliance system without the need for a mixing bottle. The maximum central heating flow temperature can be set to 53°C on the boiler printed circuit board during commissioning.

Bypass fully shut

Open 1/4 turn

Open 1/2 turn

Open 1 turn

Open 2 turns

can be piped directly to an underfloor heating

heating supply and return lines

Available pressure (kPa) between

(10 kPa = 1 m WG)

• Pipe sectional areas shall be determined in accordance with normal practices, using the output/pressure curve (diagram 3.1). The distribution system shall be calculated in accordance with the output requirements of the actual system, not the maximum output of the boiler. However, provision shall be made to ensure sufficient flow so that the temperature difference between the flow and return pipes be less than or equal to 20°C. The minimum flow is 400 l/h.

120010008006004002000

Flow rate through heating system (I/h)

Diagram 3.1

Pom 010 a

4000116705-2

SUPPLY

PIPE

AIR GAP

TUNDISH

CONTROL

VALVE

CONTROL

VALVE

TYPE CA BACKFLOW

PREVENTION DEVICE

BOILER

RETURN FLOW

HEATING

CIRCUIT

DRAIN POINT

Method 2

3 Heating System Design

• The piping system shall be routed so as to avoid any air pockets and facilitate permanent venting of the installation. Bleed fittings must be provided at every high point of the system and on all radiators.

• The total volume of water permitted for the heating system depends, amongst other things, on the static head in the cold condition. The expansion vessel on the boiler is pressurised at 0,5 bar (corresponding to a static head of 5 m w.g.) and allows a maximum system volume of 160 litres for an average temperature of 75°C and a maximum service pressure of 3 bar. This pressure setting can be modified at commissioning stage if the static head differs. An additional expansion vessel can be fitted to the system if required, see diagram 9.2.

• Provision shall be made for a drain valve at the lowest point of the system.

• Where thermostatic radiator valves are fitted, not all radiators must be fitted with this type of valve, and in particular, where a room thermostat is installed.

• In the case of an existing installation, it is ESSENTIAL that the system is thoroughly flushed prior to installing the new boiler, using a proprietary product such as Fernox or Sentinel. Contact the product manufacturers for specific details.

3.1 Bypass

• The boiler is fitted with an adjustable automatic bypass. Ensure that under no circumstances does the flow rate drop below the figure specified, see diagram 3.1.

• A bypass is not required on the central heating circuit unless the system controls could allow the boiler to operate when there is no flow.

• Where a bypass has to be fitted, the bypass must be placed at least 1.5 metres away from the appliance, see diagram 9.2.

3.2 Filling the system

• Provision for filling the system must be made, the methods are shown in diagram 3.2. There must be no permanent connection to the mains water supply, even through a non-return valve.

Note: It is important that fittings used for connection to potable water comply with the water undertakings requirements.

TEMPORARY

CONNECTION

Method 1

SUPPLY

PIPE

CONTROL VALVE

HOSE UNION

DOUBLE CHECK VALVE

HOSE

UNION

RETURN FLOW

CONTROL

VALVE

DRAIN

POINT

BOILER

HEATING

CIRCUIT

11594

Diagram 3.2

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4 Domestic Hot Water System Design

• Copper tubing or plastic Hep20 may be used for the domestic hot water system. Unnecessary pressure losses should be avoided.

• A flow restrictor limiting the flow through the boiler to a maximum of 16 l/min is fitted to the boiler.

• The boiler will operate with a minimum supply pressure of 0,7 bar, but under reduced flow rate.

Best operating comfort will be obtained from a supply pressure of 1 bar.

4.1 Hard Water Areas

In areas where the water is 'hard', more than 200mg/litre, it is recommended that a proprietary scale reducer is fitted in the cold water supply to the boiler.

A pressure reducing valve for the cold water inlet supply is provided, this is packed inside the boiler. This valve is a necessary part of the unvented system and MUST be fitted to the cold water supply, see diagram 8.1.

4.2 Domestic hot water drain point

The DHW drain point is located below the DHW pump, see diagram 4.1.

9527

Diagram 4.1

1 - Domestic thermistor 2 - Three way valve 3 - Gas control valve 4 - Ignition unit 5 - Temperature sensor for

DHW storage vessel

6 - DHW storage vessel 7 - Burner 8 - Ignition electrode 9 - Combustion chamber 10 - Heating safety valve (3 bar) 11 - Main heat exchanger 12 - Air pressure switch 13 - Water flow sensor 14 - DHW pump 15 - Non return valve 16 - Bypass 17 - Domestic plate to plate heat

exchanger

18 - Heating pump 19 - Heating expansion vessel 20 - Heating thermistor 21 - Overheat safety thermostat 22 - Flame sense electrode 23 - Fan 24 - Expansion valve (6 bar) 25 - Water pressure sensor 26 - Domestic expansion vessel (3.5

bar) 27 - Temperature pressure/ relief valve (7 bar/90°C) 28 - Pressure reducing valve and Check valve. Max. supply pressure 16 bar. (Supplied)

5 Boiler Schematic

COLD WATER

SUPPLY

A - Heating return B - Cold water inlet C - Heating flow D - Domestic hot water outlet

E - Gas D1 - Discharge from HTG

safety valves D2 - Discharge from temp/press and expansion valve (to tundish)

11749

4000116705-2

Diagram 5.1

6 Boiler Location, Flue and Ventilation

6.1 Boiler Location

The boiler may be installed in any room although particular attention is drawn to the requirements of the current issue of BS7671 with respect to the installation of a boiler in a room containing a bath or a shower. Any electrical switch or boiler control using mains electricity should be so situated that a person using the bath or shower cannot touch it. The electrical provisions of the Building Standards (Scotland) Regulations are applicable to such installations in Scotland.

The boiler must be mounted on a flat wall, which is sufficiently robust to take its total weight, see Technical Data.

If in doubt, expert advice should be obtained. In the event of the wall being found not suitable, a floor standing kit is available, contact Hepworth Heating for further details.

The boiler is not suitable for fitting outdoors.

Any electrical switch or boiler control using mains electricity must be positioned so that a person using a bath or shower cannot touch it.

6.2 Clearances

The position of the boiler must be such that there is adequate space for servicing.

The recommended clearances are shown in diagram 6.1.

20mm

600mm

25mm above elbow

300mm

11771

20mm

6.3 Cupboard or compartment ventilation

The boiler can be fitted in a cupboard or compartment without the need for permanent ventilation.

Important Note: With regards to the below boiler dimension of 300mm, please ensure that the site conditions will allow for the safety discharge pipe to be installed, if not then the dimension should be increased to 450mm.

MINIMUM CLEARANCES FROM A PERMANENT SURFACE.

Diagram 6.1

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6 Boiler Location, Flue and Ventilation

6.4 Terminal position

The minimum acceptable spacings from the terminal to obstructions and ventilation openings are shown in diagram

6.2.

The boiler must be installed so that the terminal is exposed to the external air.

Warning:

Do not obstruct the outside terminal of the boiler.

6.5 Terminal guard, see diagram 6.3

A terminal guard is required if persons could come into contact with the terminal or the terminal could be subject to damage.

If a terminal guard is required, it must be positioned to provide a minimum of 50mm clearance from any part of the terminal and to be central over the terminal.

A suitable terminal guard type K3 can be supplied by:

Tower flue components Ltd. Morley Road Tonbridge Kent TN9 1RA

11508

6.6 Flue options

There are various flue systems to choose from as follows: Horizontal telescopic top flue pack. Horizontal top flue pack. Horizontal extended flue pack. Vertical flue pack. Twin flue pack. Extensions, 90° and 45° bends.

For detailed information refer to flue options guide. This is available from your nearest stockist.

MINIMUM SITING DIMENSIONS FOR THE POSITIONING OF FLUE TERMINALS MM

HORIZONTAL FLUES

A DIRECTLY BELOW, ABOVE OR

HORIZONTALLY TO AN OPENING, AIR BRICK, OPENING WINDOWS, AIR VENT, OR ANY

OTHER VENTILATION OPENING 300 B BELOW GUTTER, DRAIN/SOIL PIPE 75 C BELOW EAVES 200 D BELOW A BALCONY OR CAR PORT 200 E FROM VERTICAL DRAIN PIPES AND

SOIL PIPES 150 F FROM INTERNAL/EXTERNAL CORNERS

OR TO A BOUNDARY ALONGSIDE THE

TERMINAL 300 G ABOVE ADJACENT GROUND OR

BALCONY LEVEL 300 H FROM SURFACE OR A BOUNDARY

FACING THE TERMINAL 600 I FACING TERMINALS 1200 J FROM OPENING (DOOR/WINDOW)

IN CAR PORT INTO DWELLING 1200 K VERTICAL FROM A TERMINAL 1500 L HORIZONTALLY FROM A TERMINAL 300

VERTICAL FLUES

M FROM ADJACENT WALL TO FLUE 300 N FROM ANOTHER TERMINAL 600 P FROM ADJACENT OPENING OR WINDOW 1000 Q ABOVE ROOF LEVEL 300

Diagram 6.2

4000116705-2

Diagram 6.3

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