baxi System 35/60, System 60/100 User guide

Download

Page 1

Baxi System 35/60 & 60/100

Gas Fired Wall Mounted System Boilers

Installation and Servicing Instructions

Please leave these instructions with the user

Page 2

Baxi UK Limited is one of the leading manufacturers

of domestic heating products in the UK.

Our first priority is to give a high quality service to our

customers. Quality is designed into every Baxi product

- products which fulfil the demands and needs of

customers, offering choice, efficiency and reliability.

To keep ahead of changing trends, we have made a

commitment to develop new ideas using the

latest technology - with the aim of continuing to make

the products that customers want to buy.

Everyone who works at Baxi has a commitment to

quality because we know that satisfied customers

mean continued success.

We hope you get a satisfactory service from Baxi. If

not, please let us know.

Natural Gas

Baxi System 35/60

G.C.No41 075 18

Baxi System 60/100

G.C.No41 075 19

Baxi is a BS-EN ISO 9001

Accredited Company

The boiler meets the requirements of Statutory Instrument “ The Boiler (Efficiency) Regulations 1993 N

3083” and is deemed to meet the requirements of Directive 92/42/EEC on the energy efficiency requirements for new hot water boilers fired with liquid or gaseous fuels:-

Type test for purpose of Regulation 5 certified by: Notified Body 0051.

Product/Production certified by: Notified Body 0051.

For GB/IE only.

Page 3

1.0 Introduction 4

2.0 General Layout 5

3.0 Appliance Operation 6

4.0 Technical Data 7

5.0 Dimensions and Fixings 9

6.0 System Details 10

7.0 Site Requirements 12

8.0 Installation 17

9.0 Commissioning the Boiler 26

10.0 Completion 28

11.0 Servicing the Boiler 29

12.0 Changing Components 31

13.0 Illustrated Wiring Diagram 39

14.0 Fault Finding 40

15.0 Short Parts List 43

Section Page

Contents

Page 4

Baxi UK Limited declare that no substances harmful to health are contained in the appliance or used during appliance manufacture.

1.1 Description

1. The Baxi System 35/60 and 60/100 are fully automatic gas fired wall mounted system boilers. They are room sealed and fan assisted.

2. The boilers are set to give a maximum output of

17.5kW (35/60) or 29.3kW (60/100).

3. They are designed for use on Natural Gas (G20) and can be converted to use Propane (35/60 & 60/100) or Butane (35/60).

4. The boiler incorporates a circulating pump and expansion vessel. It is suitable for use only on fully pumped sealed systems.

5. The boiler data badge gives details of the model, serial number and Gas Council number and is situated on the control box. It is visible when the case front panel is removed (Fig. 1).

6. The boiler is intended to be installed in residential / commercial / light industrial E.M.C. environments on a governed meter supply only.

7. The boiler must be installed with one of the purpose designed flues such as the standard horizontal flue kit, part no. 247719.

8. All systems must be thoroughly flushed and

treated with inhibitor (see section 6.1).

1.2 Installation

1. The appliance is suitable for installation only in G.B. and I.E. and should be installed in accordance with the rules in force. For Ireland install in accordance with I.S.813

“I

NSTALLATION OF GAS APPLIANCES”. The installation must be

carried out by a CORGI Registered Installer or other competent person and be in accordance with the relevant requirements of G

AS SAFETY (Installation and Use)

EGULATIONS, the BUILDING REGULATIONS (Scotland)

(Consolidation), the L

OCAL BUILDING REGULATIONS, the

URRENT I.E.E. WIRING REGULATIONS and the bye laws of the

Local Water Undertaking. Where no specific instructions are given, reference should be made to the relevant BRITISH

STANDARD CODES OF PRACTICE.

1.3 Optional Extras

Various flue extensions, bends, vertical flue kits,control accessories etc. are availble as optional extras. These are detailed in a separate publication.

1.0 Introduction

Data Badge

Fig. 1

Control Box

“Benchmark” Log Book

As part of the industry-wide “Benchmark” initiative all Baxi boilers now include an Installation, Commissioning and Service Record Log Book. Please read the Log Book carefully and complete all sections relevant to the appliance and installation. These include sections on the type of controls employed, flushing the system, burner operating pressure etc. The details of the Log Book will be required in the event of any warranty work. Also, there is a section to be completed at each subsequent regular service visit. The Log Book must be left with the user.

Case Front Panel

NOTE: This appliance must be installed in accordance with the manufacturer’s instructions and the regulations in force.Read the instructions fully before installing or using the appliance.

Page 5

2.0 General Layout

2.1 Layout

1. Air Pressure Switch

2. Expansion Vessel

3. Burner Manifold

4. Automatic Air Vent

5. Circulation Pump

6. Drain Off Point

7. Pressure Relief Valve

8. DHW Relay PCB

9. System Pressure Gauge

10. PCB

11. Control Box

12. Spark Generator

13. Flame Sensing Electrode

14. Spark Electrode

15. Burner

16. Primary Heat Exchanger

17. Fan Assembly

18. On/Off/Reset Selector Switch

19. Central Heating Temperature Control

20. Flame Failure

21. Safety Thermostat

22. Fault on Fan or Flue

23. Fault on Pump or Low System Pressure

24. Temperature Indication Only

25. Fault on Central Heating Sensor

26. Power On

27. Hot Water Mode

28. Central Heating Mode

29. Burner On

When neons 20 to 25 are constantly illuminated, they indicate the temperature of the central heating water.

30° 40° 50° 60° 70° 80°

bar

30° 40° 50° 60° 70° 80°

20 21

28 29

Page 6

3.0 Appliance Operation

3.1 Operating Mode (Fig. 2)

1. With a demand for heating, the pump circulates water through the primary circuit. At a predetermined flow rate the hydraulic differential pressure switch operates, initiating the ignition sequence.

2. The main burner ignites at low rate, then the gas valve controls the gas rate to maintain the heating temperature measured by the temperature sensor.

3. When the flow temperature exceeds the setting temperature, a 3 minute delay occurs before the burner relights automatically (anti-cycling). The pump continues to run during this period.

4. When the demand is satisfied the burner is extinguished and the pump continues to run for a period of 3 minutes (Pump Overrun).

IMPORTANT: When the selector switch is in the ‘0’ (Off) position the electrical supply to the boiler is isolated. The boiler will not operate.

3.3 Frost Protection Mode

1. The frost protection mode is integral to the appliance and functions only with the selector switch (see Section 2.1) in the domestic hot water and central heating position. If the system temperature falls below 5° C then the boiler will fire on its minimum setting until a flow temperature of 30° C is reached. Further protection can be incorporated by using a system frost thermostat.

3.4 Pump Protection

1. With the selector switch (see Section 2.1) in either the central heating or central heating and hot water position the pump will automatically operate for 1 minute in every 24 hours to prevent sticking.

10 12 11

Key

1 Heat Exchanger 2 Burner 3 Ignition Electrode 4 Flame Sensing Electrode 5 Gas Valve 6 Pump 7 Automatic Air Vent 8 Pressure Relief Valve 9 Boiler Drain Point 10 Gas Inlet 11 Boiler Flow 12 Boiler Return 13 Pressure Gauge 14 Automatic By-Pass 15 Hydraulic Differential Pressure Sensor 16 Safety Thermostat 17 Central Heating Temperature Sensor 18 Expansion Vessel 19 Water Heating Sensor

Boiler Primary Circuit

Fig. 2

Page 7

4.0 Technical Data

Flue Terminal Diameter 100mm Dimensions Projection 95mm

Outercase Dimensions

Casing Height - 780mm Overall Height Inc Flue Elbow - 980mm Casing Width - 450mm Casing Depth - 345mm

Clearances

Both Sides 5 mm Min Above Casing 200 mm Min Below Casing 200 mm Min Front 450 mm Min (For Servicing) Front 5 mm Min (In Operation)

Weights kg Packaged Boiler Carton 45 Packaged Flue Kit 3 Installation Lift Weight 37

Central Heating Primary Circuit Pressures

bar

Safety Discharge 3 Max Operating 2.5 Min Operating 0.2 Recommend Operating 1-2

Pump - Grundfos UP 15-50 Available Head See graph below

Expansion Vessel - (Integral with appliance)

bar

Min Pre-charge Pressure 0.5

litre Max Capacity of CH System 125

Primary Water Content of Boiler (unpressurised) 1.0

Connections copper tails Gas Supply - 22mm Central Heating Flow - 22mm Central Heating Return - 22mm Pressure Relief Discharge - 15mm

Temperatures

C.H. Flow Temp (adjustable)

35°C to 85°C max (± 5°C)

Heat Input (Gross)

Max Min

kW 19.4 10.6

Btu/h 66,200 36,170

Heat Output Max Min

kW 17.5 9.3

Btu/h 59,720 31,740

Electrical Supply 230V~ 50H

(Appliance must be connected to an earthed supply)

Power Consumption 170W

External Fuse Rating 3A Maximum

Internal Fuse Rating

Fuse 2A Fast Blow to BS 4265

Appliance Category CAT II

2H 3+

Max Gas Rate (Natural Gas - G20)

(After 10 Mins)

m3/h 2.05

ft3/h 72.4

Inlet Pressure (Natural Gas - G20)

mbar 20

in wg 8

Burner Injector (Natural Gas - G20)

12 x 1.28mm Diameter

Burner Pressure (Natural Gas - G20)

Max Rate Min Rate

mbar 6.9 ± 0.5 2.5 ± 0.5

in wg 2.8 ± 0.2 1.0 ± 0.2

Appliance Type C

NOxClass 3

This value is used in the UK Government’s Standard

Assessment Procedure (SAP) for energy rating of dwellings.

The test data from which it has been calculated have been

certified by 0051.

SEDBUK Declaration For System Boiler 35/60

The seasonal efficiency (SEDBUK) is 78.8 %

Electrical Protection

IPX5D

4.1 System 35/60

LPG Gases Propane - G31 and

Butane - G30

Burner Injector 12 x 0.65mm diameter Burner Pressure

Propane mbar

in wg

Butane mbar

in wg

Inlet Pressures

mbar in wg

Max Rate

36.2 ± 0.5

14.5 ± 0.2

28.8 ± 0.5

11.5 ± 0.2

Min Rate

10.8 ± 0.5

4.3 ± 0.2

7.7 ± 0.5

3.1 ± 0.2

Propane

14.8

Butane

28/30

11.2

4.5

3.5

2.5

Metre wg

1.5

0.5

l/h

Pump - Available Head

200 400 600 800 1000 1200

Page 8

4.0 Technical Data

4.2 System 60/100

Flue Terminal Diameter 100mm Dimensions Projection 95mm

Outercase Dimensions

Casing Height - 780mm Overall Height Inc Flue Elbow - 980mm Casing Width - 450mm Casing Depth - 345mm

Clearances

Both Sides 5 mm Min Above Casing 200 mm Min Below Casing 200 mm Min Front 450 mm Min (For Servicing) Front 5 mm Min (In Operation)

Weights kg Packaged Boiler Carton 47 Packaged Flue Kit 3 Installation Lift Weight 39

Central Heating Primary Circuit Pressures

bar Safety Discharge 3 Max Operating 2.5 Min Operating 0.2 Recommend Operating 1-2

Pump - Grundfos UP 15-60 Available Head See graph below

Expansion Vessel - (For Central Heating only. Integral with appliance)

bar

Min Pre-charge Pressure 0.5

litre Max Capacity of CH System 125

Primary Water Content of Boiler (unpressurised) 1.1

Connections copper tails Gas Supply - 22mm Central Heating Flow - 22mm Central Heating Return - 22mm Pressure Relief Discharge - 15mm

Temperatures

C.H. Flow Temp (adjustable)

35°C to 85°C max (± 5°C)

Heat Input (Gross)

Max Min

kW 32.6 11.9

Btu/h 111,250 40,610

Heat Output Max Min

kW 29.4 10.4

Btu/h 100,330 35,490

Electrical Supply 230V~ 50H

(Appliance must be connected to an earthed supply)

Power Consumption 190W

External Fuse Rating 3A Maximum

Internal Fuse Rating

Fuse 2A Fast Blow to BS 4265

Appliance Category CAT II

2H 3P

Max Gas Rate (Natural Gas - G20)

(After 10 Mins)

m3/h 3.45

ft3/h 122

Inlet Pressure (Natural Gas - G20)

mbar 20

in wg 8

Burner Injector (Natural Gas - G20)

15 x 1.28mm Diameter

Burner Pressure (Natural Gas - G20)

Max Rate Min Rate mbar 12.5 ± 0.5 1.8 ± 0.5 in wg 5.0 ± 0.2 0.7 ± 0.2

Appliance Type C

NOxClass 3

Electrical Protection

IPX5D

This value is used in the UK Government’s Standard

Assessment Procedure (SAP) for energy rating of dwellings.

The test data from which it has been calculated have been

certified by 0051.

SEDBUK Declaration For System Boiler 60/100

The seasonal efficiency (SEDBUK) is 78.2 %

LPG Gases Propane - G31

Burner Injector 15 x 0.77mm diameter

Burner Pressure

Propane mbar

in wg

Inlet Pressures

mbar in wg

Max Rate

34.4 ± 0.5

13.8 ± 0.2

Min Rate

5.1 ± 0.5

2.0 ± 0.2

14.8

5.5

4.5

3.5

2.5

Metre wg

1.5

0.5

l/h

Pump - Available Head

200 400 600 800 1000 1200

Page 9

5.0 Dimensions and Fixings

Dimensions

A 780mm

B 345mm

C 450mm

D 107mm Ø Min.

E 200mm

F 190mm

G 143mm

360° Orientation

Tube Ø 100mm

Heating

Return

(22mm)

Heating

Flow

(22mm)

Pressure Relief

Valve

(15mm)

Gas

Inlet

(22mm)

130 mm

65 mm

Tap Rail

Page 10

6.0 System Details

6.1 Central Heating Circuit

1. The appliance is suitable for fully pumped SEALED

SYSTEMS ONLY.

Treatment of Water Circulating Systems

• All recirculatory water systems will be subject to

corrosion unless an appropriate water treatment is

applied. This means that the efficiency of the system

will deteriorate as corrosion sludge accumulates

within the system, risking damage to pump and

valves, boiler noise and circulation problems.

• For optimum performance after installation this

boiler and its associated central heating system must

be flushed in accordance with the guidelines given in

BS 7593 “Treatment of water in domestic hot water

central heating systems”.

• This must involve the use of a proprietary cleanser,

such as BetzDearborn Sentinel X300 or X400, or

Fernox Superfloc. Full instructions are supplied with

the products, but for immediate information please

contact BetzDearborn (0151 420 9563) or Fernox

(01799 550 811) directly.

• For long term protection against corrosion and

scale, after flushing it is recommended that an

inhibitor such as BetzDearborn Sentinel X100, or

Fernox MB-1 or Copal is dosed in accordance with

the guidelines given in BS 7593.

Failure to flush and add inhibitor to the system

may invalidate the appliance warranty.

• It is important to check the inhibitor concentration

after installation, system modification and at every

service in accordance with the manufacturer’s

instructions. (Test kits are available from inhibitor

stockists.)

• For information or advice regarding any of the

above contact the Baxi Helpline.

6.2 Bypass

1. The boiler is fitted with an automatic integral bypass.

6.3 System Control

1. The boiler is designed for use in a heating system that incorporates external controls, i.e. a minimum of a timer device.

2. For optimum operating conditions and maximum economy the fitting of a programmable room thermostat, such the Baxi Combi Controller, is recommended.

Page 11

6.0 System Details

6.4 System Filling and Pressurising

1. A filling point connection on the central heating return pipework must be provided to facilitate initial filling and pressurising and also any subsequent water loss replacement/refilling.

2. The filling method adopted must be in accordance with the Water Supply (Water Fittings) regulations and the Water Bylaws (Scotland).

3. Your attention is drawn to: Paragraph 24 of Schedule 2 Section 8 of the publication Water Regulations Guide which gives recommendations and guidance on approved methods for filling sealed systems.

4. The sealed primary circuits may be filled or replenished by means of a temporary connection between the primary circuit and a supply pipe provided the arrangement in accordance with Diagram R24.2a of the Water Regulations Guide.

5. The temporary hose must be completely removed at both ends after use.

6.5 Expansion Vessel

1. The appliance expansion vessel is pre-charged to 0.5 bar. The vessel is suitable for correct operation for system capacities up to 125 litres. For greater system capacities an additional expansion vessel must be fitted - refer to BS 7074 Pt 1.

6.6 Pressure Relief Valve (Fig. 4)

1. The pressure relief valve is set at 3 bar, therefore all pipework, fittings, etc. should be suitable for pressures in excess of 3 bar.

2. The pressure relief discharge pipe should be not less than 15mm dia, run continuously downward, and discharge outside the building, preferably over a drain. It should be routed in such a manner that no hazard occurs to occupants or causes damage to wiring or electrical components. The end of the pipe should terminate facing down and towards the wall.

3. The discharge must not be above a window, entrance or other public access. Consideration must be given to the possibility that boiling water/steam could discharge from the pipe.

Fig. 3

Fig. 4

Stop Valve

Double Check Valve

Mains Cold Water

CH Return

Temporary Hose

Pressure Relief Valve

Discharge Pipe

Stop Valve

Page 12

7.0 Site Requirements

7.1 Information

1. The installation must be carried out by a CORGI Registered Installer or other registered competent person and be in accordance with the relevant requirements of the current G

AS SAFETY (Installation

and Use) R

EGULATIONS, the BUILDING REGULATIONS

(Scotland)(Consolidation), the LOCAL BUILDING REGULATIONS, the current I.E.E. WIRING REGULATIONS

and the bye laws of the LOCAL WATER UNDERTAKING. Where no specific instruction is given reference should be made to the relevant BRITISH STANDARD CODES OF PRACTICE. For Ireland install in accordance with IS 813 “I

NSTALLATION OF

GAS APPLIANCES”.

7.2 B.S. Codes of Practice

Standard Scope

BS 6891 Gas Installation. BS 5546 Installation of hot water supplies for

domestic purposes. BS 5449 Part 1 Forced circulation hot water systems. BS 6798 Installation of gas fired hot water boilers. BS 5440 Part 1 Flues. BS 5440 Part 2 Ventilation. BS 7074 Expansion vessels and ancillary

equipment for sealed water systems. BS 7593 Treatment of water in domestic hot water

central heating systems.

WARNING - The addition of anything that may interfere with the normal operation of the appliance without the express written permission of Baxi UK Limited could invalidate the appliance warranty and infringe the G

AS SAFETY (Installation

and Use) R

EGULATIONS.

7.3 Clearances (Figs. 5 & 6)

1. A flat vertical area is required for the installation of the boiler.

2. These dimensions include the necessary clearances around the boiler for case removal, spanner access and air movement. Additional clearances may be required for the passage of pipes around local obstructions such as joists running parallel to the front face of the boiler.

7.4 Location

1. The boiler may be fitted to any suitable wall with the flue passing through an outside wall or roof and discharging to atmosphere in a position permitting satisfactory removal of combustion products and providing an adequate air supply. The boiler should be fitted within the building unless otherwise protected by a suitable enclosure i.e. garage or outhouse. (The boiler may be fitted inside a cupboard-see Section 7.5).

2. If the boiler is sited in an unheated enclosure then it is recommended to leave the On/Off/Reset Selector Switch in the domestic hot water and central heating position to give frost protection.

3. If the boiler is fitted in a room containing a bath or shower reference must be made to the current I.E.E. WIRING REGULATIONS and BUILDING REGULATIONS. If the boiler is to be fitted into a building of timber frame construction then reference must be made to the current edition of Institute of Gas Engineers Publication IGE/UP/7 (Gas Installations in Timber Framed Housing).

200mm Min

780mm

450mm

200mm Min

5mm Min

450mm Min

For Servicing

Purposes

Fig. 5

Fig. 6

In Operation

Page 13

7.0 Site Requirements

7.5 Ventilation of Compartments

1. Where the appliance is installed in a cupboard or compartment, no air vents are required.

2. BS 5440: Part 2 refers to room sealed appliances installed in compartments. The appliance will run sufficiently cool without ventilation.

7.6 Gas Supply

1. The gas installation should be in accordance with BS 6891.

2. The connection to the appliance is a 22mm copper tail located at the rear of the gas service cock (Fig. 7).

3. Ensure that the pipework from the meter to the appliance is of adequate size. Do not use pipes of a smaller diameter than the boiler gas connection (22mm).

7.7 Electrical Supply

1. External wiring must be correctly earthed, polarised and in accordance with current I.E.E. Wiring Regulations.

2. The mains supply must be 230V ~ 50Hzand fused at 3A maximum.

NOTE: The method of connection to the electricity supply must facilitate complete electrical isolation of the appliance.

Connection may be via a fused double-pole isolator with a contact separation of at least 3mm in all poles and servicing the boiler and system controls only.

3. When the system includes an indirect domestic hot water cylinder it is recommended that a cylinder thermostat is used in conjunction with a 3 port 2 position valve or 2 port zone valve.

4. A switched live feed should be taken from the cylinder thermostat to the boiler. This will operate the boiler when there is a demand for domestic hot water (see Section 8.8 for details of suggested system wiring schemes).

Fig. 7

Gas Service Cock

Page 14

7.0 Site Requirements

7.8 Flue

1. The flue terminal position must be in accordance with the current editions of B.S. 5440 Part 1, and either Part J of the Building Regulations England and Wales or Part F of the Building Standards (Scotland) Regulations as appropriate.

2. If the terminal discharges onto a pathway or passageway, check that combustion products will not cause a nuisance and that the terminal will not obstruct the passageway.

3. If a terminal is less than 2 metres above a balcony, above ground or above a flat roof to which people have access, then a suitable terminal guard must be provided.

Terminal Position with Minimum Distance (Fig. 9) (mm)

A Directly below an openable window, air vent or any other

ventilation opening. 300 B Below gutter, drain/soil pipe. 25 C Below eaves. 25 D Below a balcony/car port roof. 25 E From vertical drain pipes and soil pipes. 25 F From internal or external corners. 25 G Above adjacent ground or balcony level. 300 H From a surface facing a terminal. 600 I Facing a terminals. 1200 J From opening (door/window) in carport into dwelling. 1200 K Vertically from a terminal on the same wall. 1500 L Horizontally from a terminal on the same wall. 300 M Above an opening, air brick, opening window etc. 300 N Horizontally to an opening, air brick, opening window etc. 300

H,I

B,C

Likely flue positions requiring a flue terminal guard

Fig. 9

300 min

Terminal Assembly

Top View Rear Flue

Property Boundary Line

Page 15

1.0 Introduction

7.9 Flue Dimensions

The standard horizontal flue kit allows for flue lengths between 100mm and 1m from elbow to terminal (Fig. 10).

The maximum permissible equivalent flue length is: System 35/60 5 metres

System 60/100 4 metres

7.10 Flue Terminal Trim

1. Once the flue is secure the trim can be fitted if required.

2. Remove the protective backing from the adhesive seal. Apply the seal to the rear of the trim flange (Fig. 11).

3. Locate the trim over the flue terminal and push it back to the wall to compress the seal (Fig. 12).

7.11 Terminal Guard (Fig. 13)

1. When codes of practice dictate the use of terminal guards, they can be obtained from most Plumbers’ and Builders’ Merchants.

2. There must be a clearance of at least 50mm between any part of the terminal and the guard.

3. When ordering a terminal guard, quote the appliance name and model number.

4. The flue terminal guard should be positioned centrally over the terminal and fixed as illustrated.

Fig. 10

Fig. 13

100mm

Fig. 12

Fig. 11

Flue Trim

Adhesive Seal

Page 16

7.0 Site Requirements

7.12 Flue Options

1. The Baxi System 35/60 and 60/100 can be fitted with flue systems as illustrated.

2. The standard flue is suitable only for horizontal applications.

3. Maximum permissible equivalent flue lengths are:-

35/60 60/100 Concentric 5m 4m Vertical 4m 4m Vertical Two-Pipe 15m 12m

4. Any additional “in line” bends in the flue system must be taken into consideration. Their equivalent lengths are:Concentric Pipes:

45° bend 0.5 metres 90° bend 1.0 metres

Twin Flue Pipe

45° bend 0.25 metres 90° bend 0.50 metres

The elbow supplied with the standard horizontal flue is not included in any equivalent length calculations

5. The illustrations opposite show examples of maximum equivalent lengths.

6. Full details of part numbers and descriptions of all optional flue components and kits can be found in the Baxi Gas Central Heating Boilers Installers’ Guide.

7. Instructions for guidance and fitting are included in each kit where appropriate.

Horizontal Flues

Vertical Flues

Vertical Flues (Twin Pipe)

Maximum Length = 3m (60/100) 4m (35/60) inc. 2 x 45° bends

Maximum Length =

11m (60/100)

14m (35/60)

inc. 4 x 45° bends

Maximum Length = 2m inc. 2 x 90° bends

Page 17

8.0 Installation

8.1 Initial Preparation

The gas supply, gas type and pressure must be checked for suitability before connection (see Section 7.6).

1. After considering the site requirements (see Section 7.0) position the fixing template (Fig. 14) on the wall ensuring it is level both horizontally and vertically.

2. Mark the position of the two most suitable fixing slots for the wall plate and boiler lower fixing holes. It is preferable to use the horizontal fixing slots.

3. Mark the position of the centre of the flue hole (rear exit). For side flue exit, mark as shown.

4. Note the shaded area on the template. Pipework may be routed upwards behind the boiler, providing it does not conflict with the shaded area.

5. If required, mark the position of the gas and water pipes. Remove the template.

6. Cut the hole for the flue (minimum diameter 107mm).

7. Drill the wall as previously marked to accept the wall plugs supplied. Secure the wall plate using the fixing screws.

8. Using a spirit level ensure that the plate is level before finally tightening the screws.

9. Connect the gas and water pipes to the valves on the wall plate using the copper tails supplied. Ensure that the sealing washers are fitted between the connections.

8.2 Flushing

1. Connect a tube to the central heating flow or return pipe (Fig. 15).

2. Flush thoroughly (see System Details, Section

6.2).

8.3 Preparing The Boiler

1. Remove all packaging.

2. Stand the boiler on its base by using the rear lower edge as a pivot.

NOTE: A small amount of water may drain from the boiler in the upright position.

Baxi UK Limited declare that no substances harmful to health are contained in the appliance or used during appliance manufacture.

Fig. 14

Fig. 15

System

Boiler

FIXING

TEMPLATE

5 mm Minimum

Side Clearance

5 mm Minimum Side Clearance

Horizontal Side Flue Centre Line

107mm Dia Minimum Aperture For Flue Tube

200 mm

Minimum

Clearance

200 mm

Minimum

Clearance

Profile of Outercase

Vertical Flue Centre Line

General Area For Electrical Supply

Heating

Return

(22mm)

Heating

Flow

(22mm)

Pressure Relief

Valve

(15mm)

Gas Inlet

(22mm)

95 mm

130 mm

Boiler Mounting Bracket Fixing Slots

Drill 8 mm diameter x 50 mm deep

130 mm

65 mm

Boiler Lower Fixing Holes

Drill 8 mm diameter x 50 mm deep

IMPORTANT

Keep rear routed pipework, clips

and electrical cables clear of all

shaded areas to allow the

correct fitting of the boiler chassis

Fixing Template

Appliance Wall Plate

190mm

For Side Flue Exit

Central Heating Return

Flushing Tube

Wall Plate

Page 18

8.0 Installation

8.4 Fitting The Boiler

1. Remove the sealing caps from the boiler connections.

2. Lift the boiler using the lower edges. Engage the slots at the top rear of the boiler on the wall plate (Fig. 16).

3. Insert the sealing washers between the valves and pipes on the wall plate and the boiler connections. The rubber washers must be

used on the gas connection.

4. Tighten all the connections.

5. Secure the boiler side panels to the boiler wall plate flanges using the screws provided (Fig. 16).

8.5 Fitting the Pressure Relief

Discharge Pipe (Fig. 17)

1. Remove the discharge pipe from the kit.

2. Determine the routing of the discharge pipe in the vicinity of the boiler. Make up as much of the pipework as is practical, including the discharge pipe supplied.

3. The pipework must be at least 15mm diameter and run continuously downwards to a discharge point outside the building. See section 6.6 for further details.

4. Utilising one of the sealing washers, connect the discharge pipe to the adaptor and tighten the nut.

5. Complete the discharge pipework and route it to the outside discharge point.

IMPORTANT: Make all soldered joints before connecting to the pressure relief valve.

Fig. 17

Fig. 16

Pressure Relief Valve

Wall Plate

Discharge Pipe

Page 19

8.0 Installation

8.6 Fitting The Flue

HORIZONTAL FLUE

1. The standard flue is suitable for lengths 100mm minimum to 1m maximum (measured from the edge of the flue elbow outlet).

Rear Flue: maximum wall thickness - 900mm

Side Flue: maximum wall thickness - 870mm

2. Locate the flue elbow on the adaptor at the top of the boiler. Set the elbow to the required orientation (rear, right or left).

3. Measure the distance from the outside wall face to the elbow (Fig. 18). This dimension will be known as ‘X’.

4. Taking the air duct, mark dimension ‘X’ as shown (Fig. 19). Measure the length of waste material, and transfer the dimension to the flue duct (Fig. 19).

IMPORTANT: Check all measurements before cutting.

5. Remove the waste from both ducts. Ensure that the cut ends are square and free from burrs.

6. Remove the flue elbow from the adaptor.

7. Insert the flue duct into the air duct and pass them through the hole in the wall.

Wall Thickness

(X)

Wall Thickness

(X)

Fig. 18

Waste

(X)

Waste

Fig. 19

Air Duct

Flue Duct

Page 20

8.0 Installation

8.6 Fitting the Flue (Cont)

IMPORTANT: If the equivalent flue length is

greater than 1.5m the restrictor MUST be removed from the adaptor (Fig. 20).

8. Take one of the rubber seals and position it on the boiler flue adaptor. Engage the flue elbow on the adaptor and pull the sleeve up so that it equally covers the joint (Fig. 20).

9. Remove the screws from one of the clips provided. Prise the clip apart and fit it over the seal (Fig. 21). Set the elbow to the required angle.

10. Refit the screws to the clip and tighten them to secure the elbow. Take the second rubber seal and position it on the flue elbow.

11. Locate the flue duct clamp on the flue outlet elbow. Draw the flue duct out of the air duct, engage it in the clamp and tighten the screws (Fig. 22).

12. Draw the air duct out of the wall and align it with the elbow. Position the seal so that it equally covers the joint (Fig. 23).

13. Remove the screws from the second clip provided. Prise the clip apart and fit it over the seal. Refit the screws to the clip and tighten them (Fig. 23).

14. Where possible position the clips so that the screws are not visible.

15. Make good between the wall and air duct outside the building.

16. Fit the circular flue trim outside if required, and if necessary fit a terminal guard (see Section 7.10 & 7.11).

8.7 Extensions & Additional Elbows

1. The method of connecting any flue extensions or additional elbows is the same as that for connecting the standard flue and 90° elbow as described above.

2. If, for example, when a flue extension is connected to a 90° elbow the flue duct will project from the air duct at the unconnected end by the same ammount as the flue duct spigot does from the elbow . Further elbows or extensions can then be added to this.

3. Similarly, a concentric flue can be connected to the boiler adaptor in the same manner as it does to the elbow to provide a vertical flue.

4. The additional 90° elbow available is identical to the elbow supplied with the standard flue. 45° elbows are of the same principle.

5. Extensions can be cut according to the requirements of the installation.

Fig. 20

Fig. 21

Fig. 22

Seal

Adaptor

Seal

Clip

Screws

Flue Duct Clamp

Flue Duct

Air Duct

Seal

Clip

Screws

Fig. 23

Restrictor

Elbow

Page 21

8.0 Installation

8.8 Making The Electrical Connections

To connect the mains input cable proceed as follows:-

1. Slacken the facia securing screws and lift the outercase panel so that its securing tabs are clear of the facia. Remove the panel.

2. Remove the screws securing the facia panel and hinge it down (Fig. 24).

3. Remove the control box cover securing screws. Disengage the barbs on the control box from the cover. Remove the cover (Fig. 25).

4. Slacken the cable clamp on the LH side of the boiler chassis (Fig. 26). Insert the cable through the clamp and route it to the terminal block.

5. Slacken the screws in the terminal block, connect the input cable, and tighten the screws.

6. If an external control is to be connected it can be done at this point. Run the input cable from the external control through the second cable clamp on the boiler chassis. Refer to the instructions supplied with the control.

7. To connect external control(s) remove the link between terminals 1 & 2. The switched output from the external control must be connected to terminal 2 (Fig. 27).

8. Any domestic hot water control should be connected to the DHW relay PCB (Fig. 24) in most installations. See Section 8.8 for details of suggested system wiring schemes

IMPORTANT: The external control MUST be suitable for 230V switching and fused 3A maximium

9. Ensure that both mains input and, where fitted, external control input cables have sufficient slack to allow the control box to drop down. Tighten the cable clamp(s) on the boiler chassis.

Always fit fast

blow 2A fuse

230V ~ 50Hz

fused 3A maximum

Live (brown)

Neutral (blue)

Earth (green/yellow)

230V S/L from

external control

g/y

230 V

Selector /

Reset Switch

External Controls

br b

Pump

Hydraulic Differential Pressure Switch

Safety Overheat Thermostat

Central Heating

NTC Sensor

Gas Valve

Spark Electrode

Spark

Generator

Flame Sensing Electrode

br b

Fan

bk bk

Pressure Switch

b br

PCB

Primary Return Sensor

Gas Valve Modulator

DHW

Controls

DHW Relay

PCB

g g

L N

Fig. 26

Fig. 25

Fig. 27

Fig. 28

Fig. 24

Terminal Block

Internal Fuse

Cable Clamp

Control Box Cover

Facia Panel

Functional Flow Diagram

Key to Wiring

b - blue br - brown bk - black r - red g - green

D.H.W. Connections

(DHW Relay PCB)

Page 22

8.0 Installation

8.9 System Wiring

1. The system should include a domestic hot water cylinder thermostat, room thermostat, timer and zone valve(s).

2. A system frost protection thermostat is shown in each diagram. This is in addition to the boiler frost protection thermostat that is integral to the appliance.

3. When the boiler selector switch is in the central heating and domestic hot water position there will be a 230V supply at terminal 1 of the boiler terminal strip.

4. The boiler incorporates a domestic hot water thermostat that allows a maximum temperature of 65°C. For this feature to operate the boiler requires a switched live feed to the domestic hot water relay PCB.

5. Methods of wiring several typical heating schemes are shown. In Scheme 1 the boiler does not differentiate between central heating and domestic hot water demands. With Schemes 2, 3 & 4 the boiler utilises the benefit of the integral domestic hot water thermostat referred to above which overrides any temperature requirements of the central heating control(s).

6. It is recommended that the central heating temperature control is always set at maximum.

Scheme 1

7. Scheme 1 shows the use of a 3 port mid position zone valve and is based on a ‘Y’ plan system. The boiler will provide hot water to the central heating system, domestic hot water store or both.

8. A live feed to terminal 2 of the boiler terminal strip controls the boiler. This feed is taken from either the DHW cylinder thermostat or via the mid position valve depending upon demand.

9. The timer must supply a signal to the zone valve when there is no hot water demand in order that port ‘B’ may be closed off.

10. It is not necessary to connect any control(s) to the boiler domestic hot water relay PCB. As a result of this the domestic hot water thermostat will not operate and the cylinder thermostat must be relied upon to limit the temperature of DHW.

11. The selector switch must be in the central heating and domestic hot water position at all times for the boiler to operate.

E12NL

Terminal Block

312

Room

Thermostat

12345678910

Cylinder

Thermostat

Frost

Thermostat

3 Port Valve Mid Position

Timer

230V 50Hz

L N HTG HW On HW Off

g/y

fused 3A maximum

Scheme 1

b - blue w - white o - orange gr - grey

g/y - green/yellow

Baxi System

Boiler

Page 23

8.0 Installation

8.9 System Wiring (cont)

Scheme 2

12. Scheme 2 incorporates two 2 port zone valves and is based on an ‘S’ plan system. The boiler will provide hot water to the central heating system, domestic hot water store or both.

13. The boiler is controlled by a live feed from either zone valve depending upon demand.

14. The domestic hot water relay PCB is fed from the domestic hot water zone valve. Central heating demand is controlled by a live feed to terminal 2 on the boiler terminal strip from the central heating zone valve.

15. When there is a demand for domestic hot water the boiler will not supply water at a temperature greater than 65°C irrespective of the setting of any central heating control(s) or if the cylinder thermostat is set higher.

16. Additional 2 port zone valves may be incorporated in the system as required and wired in the same manner as the basic system.

Scheme 3

17. Scheme 3 shows the use of a 3 port two position zone valve and is based on a ‘W’ plan system. The boiler will provide hot water to the central heating system or domestic hot water store.

18. When there is a demand for domestic hot water and the cylinder thermostat is not satisfied the zone valve will be energised to open port ‘A’.

19. The zone valve is installed so that port ‘A’ is connected to the domestic hot water circuit and port ‘B’ to central heating. This is the reverse of a conventional ‘W’ plan. It ensures that the valve is energised only when there is a hot water demand, not for long periods i.e. central heating demand.

20. The boiler is controlled by a live feed from either room or cylinder thermostat depending upon demand.

21. The domestic hot water relay PCB is fed from the cylinder thermostat. Central heating demand is controlled by a live feed to terminal 2 on the boiler terminal strip from the room thermostat.

22. Whilst there is a domestic hot water demand the central heating circuit will not be served. Once the cylinder thermostat is satisfied the zone valve allows circulation of water through the heating circuit even if the timer still calls for domestic hot water.

23. When there is a demand for domestic hot water the boiler will not supply water at a temperature greater than 65°C even if the cylinder thermostat is set higher.

E12N

Relay Board

PCB

Terminal Block

312

Room

Thermostat

12345678 910

Cylinder

Thermostat

Zone Valve

DHW

Timer

230V 50Hz

Zone Valve

HTG

Motor

Frost

Thermostat

g/y

fused 3A maximum

Scheme 2

b - blue w - white o - orange br - brown gr - grey

g/y - green/yellow

Scheme 3

Baxi System

Boiler

Baxi System

Boiler

PCB

Relay Board

230V 50Hz

fused 3A maximum

Timer

Room

Thermostat

g/y

312

DHW

3 Port Valve

2 Position

Terminal Block

12NL

12345678910

HTG

DHW

Frost

Thermostat

HTG

Cylinder

Thermostat

Page 24

8.0 Installation

E12NL

Terminal Block

312

Room

Thermostat

12345678910

Cylinder

Thermostat

Frost

Thermostat

3 Port Valve

2 Position

Timer

230V 50Hz

L N HTG HW On HW Off

g/y

PCB

Relay Board

fused 3A maximum

8.9 System Wiring (cont)

Scheme 4

24. Scheme 4 utilises an existing 3 port mid position zone valve and is based on a ‘Y’ plan system but with significant changes. The zone valve operates as a two position type and the boiler is controlled as in Scheme 3.

25. To convert a standard ‘Y’ plan to Scheme 4 proceed as follows:-

i) Change the orientation of the zone valve so that port ‘A’ serves domestic hot water and port ‘B’ the central heating.

ii) Remove the wire between 7 on the terminal strip and terminal 2 of the cylinder thermostat.

iii) Disconnect the orange zone valve wire from 8 on the terminal strip and connect to 9.

iv) Disconnect the grey zone valve wire from 7 on the terminal strip and connect to 8.

v) Disconnect the white zone valve wire from 5 on the terminal strip and connect to 8.

vi) Connect 8 on the terminal strip to switched live on the domestic hot water relay PCB.

vii) Connect 5 on the terminal strip to terminal 2 of the boiler terminal block.

26. For isolation purposes both the orange zone valve wire and the live signal from the timer to close the domestic hot water port of the zone valve are connected to “dead” points on the terminal strip.

b - blue w - white o - orange gr - grey

g/y - green/yellow

Scheme 4

Baxi System

Boiler

Page 25

8.0 Installation

8.10 Domestic Hot Water Wiring

The boiler can be wired to operate when there is a demand for replenishment of an indirect domestic hot water storage cylinder.

1. If not already done, slacken the facia securing screws sufficiently to release the outercase panel securing tabs. Lift and remove the panel.

2. Remove the screws securing the facia panel and hinge it down.

3. Slacken the cable clamp on the R.H. side of the boiler chassis. Insert the cable from the cylinder thermostat through the cable clamp.

4. Undo the screws securing the DHW relay PCB cover. Remove the cover. Slacken the screws in the terminal block on the PCB and connect the switched live and neutral (Fig. 29).

5. Lay the input cable in the cut out in the relay PCB housing and refit the cover and screws.

6. Ensure that the input cable has sufficient slack to allow the control box to drop down. Tighten the cable clamp on the boiler chassis.

8.11 Preliminary Electrical Checks

1. Prior to commissioning the boiler preliminary electrical system checks should be carried out.

2. These should be performed using a suitable meter, and include checks for Ground Continuity, Resistance to Ground, Short Circuit and Polarity.

Fig. 29

DHW Relay PCB Cover

DHW Control Input Cable

DHW Relay PCB

Facia Panel

Page 26

9.0 Commissioning the Boiler

9.1 Commissioning the Boiler

1. Reference should be made to BS 5449 when commissioning the boiler.

2. Ensure that the filling loop is connected and open, then open the heating flow and return valves on the boiler.

3. Open the screw on the automatic air vent (Fig. 30).

4. The system must be flushed in accordance with BS 7593 and the flushing agent manufacturers instructions.

5. Pressurise the system to 0.2 bar then close and disconnect the filling loop.

6. Turn the gas supply on and purge the system according to BS 6891.

7. Test for gas soundness.

8. If at any time during commissioning it is required to terminate a particular cycle, e.g. the pump overrun period, turn the selector to the Off position and then back to the On position ( ) (Fig. 32).

Automatic

Air Vent

Pressure

Gauge

Screw

bar

Fig. 30

Selector Switch

Central Heating

Temperature Control

Fig. 31

30° 40° 50° 60° 70° 80°

bar

Pump

Fig. 32

Power On

Neon

Page 27

9.0 Commissioning the Boiler

OUT

MIN

Pressure Test Point Sealing Screw

Fig. 33

9.2 Checking the Burner Pressure

1. Turn on the gas and electrical supplies to the boiler and ensure that all external controls are calling for heat.

2. Set the temperature control to maximum and the selector switch to the Off position (Fig. 36).

3. Slacken the pressure test point sealing screw on the gas valve and connect a pressure gauge (Fig. 33).

4. Undo the screws securing the inner door panel. Lift the panel slightly to disengage it from the studs on top of the case.

5. Turn the selector switch fully anticlockwise against the spring pressure to position R and hold for 2 seconds to reset the boiler.

6. Turn the selector switch to the Cental Heating and Domestic Hot Water position ( ). The power On neon ( ) will illuminate (Fig. 36).

7. The pressure should be as quoted in Section

4.0 Technical Data. If not, check that the gas supply pressure is correct (Natural Gas 20mbar, Butane 30mbar and Propane 37mbar).

8. The pressure can be adjusted if required.

9. To check and set minimum pressure first remove one of the modulator wires.

Adjusting the Pressure (Fig 34)

10. Remove the plastic protection cap from the pressure adjustment nuts on the valve.

11. The smaller nut (5mm) adjusts minimum pressure and the larger nut (8mm) maximum pressure.

12. Using a suitable spanner adjust the relevant nut until the correct pressure is achieved.

13. Once the pressure has been set turn the boiler off and disconnect the pressure gauge.

14. Tighten the pressure test screw and refit the modulator to the valve. Reassemble in reverse order.

Selector Switch

Temperature Control

30° 40° 50° 60° 70° 80°

bar

Fig. 36

Power On Neon

Pressure

Gauge

bar

Fig. 35

Gas Valve

Fig. 34

Plastic Protection Cap

Modulator Wire

Maximum Rate Adjustment Nut

Minimum Rate Adjustment Nut

Page 28

10.0 Completion

10.1 Completion

1. Hinge the facia panel upwards and refit the case front panel. Secure them with the screws previously removed (Fig. 37).

2. Instruct the user in the operation of the boiler and system, explaining the operational sequence.

3. Carefully read and complete all sections of the “Benchmark” Installation, Commissioning and Service Record Log Book that are relevant to the appliance and installation. The details of the Log Book will be required in the event of any warranty work. The Log Book must be handed to the user for safe keeping and each subsequent regular service visit recorded.

4. Hand over the Users Operating, Installation and Servicing Instructions and the Log Book, giving advice on the necessity of regular servicing.

Fig. 37

Facia Panel

Case Front Panel

Page 29

11.0 Servicing the Boiler

11 .1 Annual Servicing

1. For reasons of safety and economy, it is recommended that the boiler is serviced annually. Servicing must be performed by a competent person.

2. After servicing, complete the relevant section of the “Benchmark” Installation, Commissioning and Service Record Log Book. This should be in the possession of the user.

3. Ensure that the boiler is cool.

4. Ensure that both the gas and electrical

supplies to the boiler are isolated.

5. Slacken the screws securing the facia panel. Lift the outercase panel so that its securing tabs are clear of the facia. Remove the panel (Fig. 38).

6 Remove the facia securing screws and hinge the panel down.

7. Remove the screws (2 on 35/60, 4 on 60/100) securing the inner door panel. Lift the panel slightly to disengage it from the studs on top of the case (Fig. 39).

8. Note the positions of the two sensing tubes on the outlet elbow and three wires on the fan motor and remove them (Fig. 40).

9. Slacken the screws on the outlet sealing collar. Ease the collar upwards as far as possible (Fig. 40).

10. Remove the four screws securing the combustion box door and remove the door (Fig. 39).

Fan Wires

Fan

Sensing

Tubes

Outlet Sealing

Collar

Combustion

Box Door

Inner Door

Panel

Case Front Panel

Ease Outlet Sealing

Collar Upwards

Fig. 38

Facia Panel

Securing Screws

Fig. 41

Fig. 40

Inner Door

Panel

Combustion

Box Door

35/60 models

60/100 models

Page 30

11.0 Servicing the Boiler

11.1 Annual Servicing (Cont)

11. Remove the spring clips retaining the air box side baffle plates. Disengage the tabs on the baffles from the slots in the fan hood (Fig. 41).

12. Undo the screws securing the fan and hood to the appliance back panel. Draw the assembly forwards (Fig. 42).

13. Undo the screws securing the burner to the injector manifold (60/100 model only). Draw the burner out of the combustion box, pulling the electrode grommets from the slots in the combustion box lower panel (Fig. 43).

14. Disconnect the electrode leads and grommets from the electrodes. Completely remove the burner (Fig. 43).

15. Brush any deposits from the injectors. Do not use a pin or wire to clean them.

16. Brush the burner blades and venturis and clean the combustion box.

17. Ensure that the heat exchanger fins are clear of any obstruction.

18. Check that the pressure vessel charge is

0.5bar and reassemble in reverse order of dismantling.

19. Turn the selector switch fully anticlockwise against the spring pressure to position R and hold for 2 seconds to reset the boiler before recommissioning.

20. Complete the relevant section of the “Benchmark” Installation, Commissioning and Service Record Log Book and hand it back to the user.

Spring Clip

Fan and Hood

Assembly

Baffle

Tab

Burner

Electrode

Grommets

Fig. 41

Fig. 43

Fig. 42

Page 31

12.0 Changing Components

IMPORTANT: When changing components ensure that both the gas and electrical supplies to the boiler are isolated before any work is started. When the new component has been fitted turn the selector switch fully anticlockwise against the spring pressure to position R and hold for 2 seconds to reset the boiler before recommissioning.

See Section 11.1 “Annual Servicing” for removal of case panel, door etc.

12.1 Pressure Switch (Fig. 44)

1. Note the positions of the two sensing tubes and three wires and remove them.

2. Remove the two screws holding the pressure switch to the combustion box top panel.

3. Fit the new pressure switch and reassemble all components in reverse order of dismantling.

12.2 Fan (Figs. 45 & 46)

1. Note the positions of the two sensing tubes on the outlet elbow and three wires on the fan motor and remove them.

2. Slacken the screws on the outlet sealing collar. Ease the collar upwards as far as possible.

3. Remove the four screws securing the combustion box door and remove the door.

4. Remove the spring clips retaining the air box side baffle plates. Disengage the tabs on the baffles from the slots in the fan hood.

5. Undo the screws securing the fan hood to the appliance back panel, and draw the fan and hood assembly forwards.

6. Remove the screws and spring washers securing the fan to the hood.

7. Fit the new fan to the hood using the screws and spring washers previously removed.

8. Reassemble in reverse order of dismantling.

Spring Clip

Fan

Fan Hood

Spring Washer

Securing Screw

Baffle

Tab

Fan Wires

Fan and Hood Assembly

Sensing Tubes

Outlet Sealing

Collar

Pressure Switch

Sensing Tubes

Pressure

Switch Wires

Fig. 44

Fig. 45

Fig. 46

Page 32

12.0 Changing Components

12.3 Heat Exchanger (Fig. 47)

1. Note the positions of the two sensing tubes on the outlet elbow and three wires on the fan motor and remove them.

2. Slacken the screws on the outlet sealing collar. Ease the collar upwards as far as possible.

3. Remove the four screws securing the combustion box door and remove the door.

4. Remove the spring clips retaining the air box side baffle plates. Disengage the tabs on the baffles from the slots in the fan hood.

5. Undo the screws securing the fan hood to the appliance back panel, and draw the fan and hood assembly forwards.

6. Drain the primary circuit. Prise the two pipe connecting clips off the joints in the flow and return pipes.

7. Lift the heat exchanger to disconnect the flow and return pipe joints. Withdraw it from the appliance, taking care not to damage the rear insulation piece.

8. Fit the new heat exchanger.

9. Reassemble in reverse order of dismantling, and repressurise the system.

12.4 Burner (Fig. 48)

1. Remove the four screws securing the combustion box door and remove the door.

2. Undo the screws securing the burner to the injector manifold (60/100 model only). Draw the burner out of the combustion box, pulling the electrode grommets from the slots in the combustion box lower panel.

3. Disconnect the electrode leads and grommets from the electrodes. Completely remove the burner.

4. Undo the screws securing the electrodes to the burner. Examine the condition of the electrodes, replacing if necessary. Fit the electrodes to the new burner.

5. Engage the burner location brackets over the studs on the injector manifold and reassemble in reverse order.

Burner

Electrode

Grommets

Electrode

Leads

Electrodes

Heat Exchanger

(35/60 model)

Fig. 47

Heat Exchanger

(60/100 model)

Pipe Connecting Clips

Fig. 48

Page 33

12.0 Changing Components

12.5 Injectors (Fig. 49)

1. Remove the burner as described in Section

12.4.

2. Undo the screws securing the injector manifold to the inlet elbow and remove the manifold.

3. Unscrew and replace injectors as required and examine the sealing gasket, replacing as necessary. Reassemble in reverse order.

12.6 Electrodes (Fig. 49)

1. Remove the four screws securing the combustion box door and remove the door.

3. Disconnect the lead and grommet from the electrode being replaced. Undo the securing screw and withdraw the electrode to the burner.

4. Reassemble in reverse order.

12.7 Insulation (Fig. 50)

1. Remove the four screws securing the combustion box door and remove the door.

2. Slide the side insulation pieces carefully out of their carriers.

3. To replace the rear insulation piece it is necessary to remove the heat exchanger as described in Section 12.3 and slide out the side pieces.

4. The combustion box door insulation piece can be replaced by carefully bending up the two retaining tabs.

5. Replace all insulation pieces and reassemble in reverse order.

13.8

Injector

Manifold

Inlet Elbow

Gasket

Injector

Burner

Electrode Grommets

Electrode

Leads

Side Insulation

Rear Insulation

Front Insulation

Combustion

Box Door

Side Insulation

Electrodes

Fig. 49

Fig. 50

Page 34

12.0 Changing Components

12.8 Gas Valve (Fig. 51)

1. Undo the nut on the gas feed pipe under the boiler.

2. Remove the securing screws and hinge the facia panel down.

3. Disconnect the earth wire and pressure sensing pipe from the valve. Undo the screw securing the electrical plug to the valve and disconnect the plug. Disconnect the wires from the valve modulator.

4. Remove the screws securing the inlet pipe flange to the boiler bottom panel and those securing the outlet manifold to the burner manifold.

5. Remove the valve from the boiler.

6. Note the orientation of the inlet pipe and outlet manifold. Undo the securing screws and remove the pipe and manifold.

7. Examine the ‘O’ ring seals for damage, replacing as necessary.

8. Fit the inlet pipe and outlet manifold to the new valve, ensuring that the ‘O’ ring seals are in place.

9. Reassemble in reverse order and check the burner pressure as described in Section 9.2.

12.9 Central Heating Temperature Sensor

(Fig. 52)

1. Ease the retaining tab on the sensor away and disconnect the electrical plug.

2. Unscrew the sensor from it’s pocket and reassemble in reverse order. The plug will only fit one way.

12.10 Safety Thermostat (Fig. 52)

1. Pull the electrical connections off the thermostat.

2. Remove the screws securing the thermostat to the mounting plate on the flow pipe.

3. Reassemble in reverse order. The thermostat is not polarised - either wire can fit either terminal on the thermostat.

12.11 Return Heating

Temperature Sensor

(Fig. 53)

1. Ease the retaining tab on the sensor away and disconnect the electrical plug.

2. Prise the sensor retaining clip off the pipe and remove the sensor from the clip.

3. Reassemble in reverse order.

Gas Valve

Inlet Pipe

Gas Feed

Pipe

Earth Wire

Electrical

Plug

Central Heating

Temperature Sensor

Safety

Thermostat

Return Heating Temperature Sensor

Retaining Clip

Heating Return Pipe

Flow Pipe

Fig. 51

Fig. 52

Fig. 53

Modulator

Wires

Page 35

12.0 Changing Components

12.12 Pump - Head Only (Fig. 54)

1. Drain the primary circuit and remove the socket head screws securing the pump head to the body and draw the head away.

2. Undo the screw on the pump wiring cover and remove the cover. Using a suitable flat bladed screw driver press the cable securing levers downwards to release each wire after noting their position.

3. A standard Grundfos replacement head can now be fitted. A Grundfos 15-50 head is suitable for the System 35/60. The System 60/100 requires a 15-60 head. Connect the wiring to the new head. The pump speed must be set to 3 (Fig. 55).

4. Reassemble in reverse order.

12.13 Pump - Complete (Fig. 56)

1. Drain the primary circuit and unscrew the automatic air vent from the pump body. Undo the two screws securing the body to the pipe and manifold and draw the pump forwards.

2. Undo the screw on the pump wiring cover and remove the cover. Using a suitable flat bladed screw driver press the cable securing levers downwards to release each wire after noting their position.

3. Connect the wiring to the new pump. Examine the ‘O’ ring seals on the return pipe and manifold, replacing if necessary.

4. Fit the air vent to the pump body and reassemble in reverse order.

12.14 Automatic Air Vent (Fig. 56)

1. Drain the primary circuit and unscrew the automatic air vent from the pump body.

2. Examine the ‘O’ ring seal, replacing if necessary, and fit it to the new automatic air vent.

3. Reassemble in reverse order.

Pump Setting

Pump Wiring

Cover

Socket Headed

Screw

Pump Head

Pump Body

Pump Wiring

Cover

Automatic

Air Vent

Fig. 54

Fig. 56

Fig. 55

Page 36

12.0 Changing Components

12.15 Pressure Gauge (Figs. 57 & 58)

1. Drain the primary circuit and undo the nut on the pressure gauge capillary.

2. Remove the timer cover and ease the timer wiring aside. Undo the screws securing the gauge retaining bracket.

3. Remove the bracket and gauge assembly. Depress the barbs on the side of the gauge and remove the retaining bracket.

4. Reassemble in reverse order.

12.16 Expansion Vessel (Fig. 59)

1. To replace the expansion vessel it is necessary to remove the boiler from the wall.

NOTE: Alternatively a vessel of equivalent capacity can be fitted on the system return pipe as close as possible to the boiler.

2. Drain the system and undo all gas and water connections. Remove the flue elbow.

3. Lift the boiler off the wall plate and lay it on either side on a clean flat surface.

4. Undo the nut on the vessel outlet spigot, and remove the locknut and spring washer securing the spigot to the boiler chassis.

5. Undo the screws and remove the appliance upper cross member. Slide the expansion vessel out of the retaining clips.

6. Reassemble in reverse order. Fully recommission the appliance and system.

12.17 Spark Generator (Fig. 60)

1. Pull the electrode lead off the spark generator. Remove the screws and spring washers securing the generator to its mounting bracket.

2. Pull the rubber shroud off the generator input plug and disconnect the plug.

3. Reassemble in reverse order.

Pressure Gauge

Timer Cover

Pressure Gauge

Capillary

Gauge Retaining

Bracket

Expansion Vessel

Retaining Clip

Vessel Outlet

Spigot

Boiler

Chassis

Lock Nut

Spring

Washer

Electrode Lead

Spark Generator

Mounting Bracket

Fig. 57

Fig. 58

Fig. 59

Fig. 60

Upper Cross

Member

Page 37

12.0 Changing Components

12.18 DHW Relay PCB (Fig. 62)

1. Undo the screws securing the DHW relay PCB cover. Remove the cover.

2. Remove the screws securing the control box cover and release the cover retaining barbs from their slots. Disengage the rear of the cover from the control box hinge pin.

3. Disconnect the live feed and neutral from the external control at the relay PCB.

4. Disconnect the green wires from the 2-way electrical connection block adjacent to the main PCB. Undo the securing screws and remove the relay PCB.

6. Reassemble in reverse order.

12.19 Main PCB (Fig. 62)

1. Note the setting of the temperature control knob. Rotate the knob fully anticlockwise and carefully pull it off the drive pin.

2. Remove the screws securing the control box cover and release the cover retaining barbs from their slots. Disengage the rear of the cover from the control box hinge pin (Fig. 61).

3. Note the position of all plugs and wires on the PCB and disconnect them.

4. Undo the securing screws and remove the PCB. Transfer the control knob drive pin to the new PCB and turn it fully anticlockwise.

5. Reassemble in reverse order, ensuring that the temperature controller is reset to the previous position.

6. Ensure that the DHW potentiometer is fully anticlockwise once the new PCB is fitted.

12.20 Selector Switch (Fig. 62)

1. Note the setting of the selector switch knob and carefully pull it off the facia.

2. Remove the screws securing the control box cover and release the cover retaining barbs from their slots. Disengage the rear of the cover from the control box hinge pin.

3. Note the position of the electrical connections and the orientation of the switch. Remove the electrical connections.

4. Remove the screws securing the switch to the facia panel.

5. Fit the new switch, ensuring that it is correctly positioned and reassemble in reverse order.

Control Box Cover

PCB

Selector

Switch

Facia

Selector Switch Knob

Temperature Control Knob

Fig. 61

Fig. 62

Control Knob

Drive Pin

DHW Relay

PCB

DHW

Potentiometer

Page 38

12.0 Changing Components

12.21 Central Heating Differential Valve

(Figs. 63 & 64)

1. Drain the primary circuit.

2. Undo the screw securing the microswitch to the differential valve. Allow the microswitch to rest to one side.

3. Undo the pressure gauge capillary nut and heating flow pipe nut from the valve.

4. Prise off the bypass connecting clips and disconnect the heating flow tap. Undo the screws securing the valve to the boiler bottom panel. Remove the valve.

5. Remove the screws securing the cover from the valve body. Examine the condition of the diaphragm, spring and pushrod, replacing as necessary.

6. If required the complete valve assembly can be replaced.

7. Examine the sealing washers and ‘O’ ring on the pipes and capillary, replacing as necessary.

12.22 Central Heating Differential Valve

Microswitch (Fig. 64)

1. Remove the two wires from the microswitch.

2. Undo the screw securing the microswitch to the valve body.

3. Reassemble in reverse order.

12.23 Pressure Relief Valve (Fig. 65)

1. Drain the primary circuit.

2. Disconnect the discharge pipe from the valve. Using a suitable hexagon key undo the grub screw sufficiently to release the valve.

3. Note the orientation of the valve, rotate it and withdraw it from the manifold.

4. Fit the new valve and ‘O’ ring seal and set to the previously noted orientation. Reassemble in reverse order.

Microswitch

Bracket

Diaphragm

Fig. 63

Fig. 64

Pressure Relief Valve

Grub Screw

‘O’ ring seal

Discharge Pipe

Fig. 65

Page 39

13.0 Illustrated Wiring Diagram

- brown

- black

- blue

- red

br bk b r

- green

- green / yellow

- white

g g/y w

Return Heating Temperature Sensor

Reset Selector Switch

Control PCB

A1 A2

212 3341

234 12

454

556789

Central Heating NTC Sensor

Fan

Gas Valve

Overheat Stat

Hydraulic Differential Pressure Switch

Air Pressure

Switch

Flame

Mains Input

Fuse

Link

g/y

Sensing

Electrode

Pump

bbrbb

bkbrbr

Spark Generator

Relay Board

Cylinder Stat

Input

S/L

Page 40

14.0 Fault Finding

Carry out initial fault finding checks

1. Check that gas, water and electrical supplies are available at the boiler. Electrical supply = 230V ~ 50 Hz. CH water system pressurised to 0.5 bar when the boiler is cold. The preferred minimum gas pressure is 19.5mbar (natural gas), 27mbar (butane) or 36mbar (propane).

2. Carry out electrical system checks, i.e. Ground Continuity, Resistance to Ground, Short Circuit and Polarity with a suitable meter. NOTE: These checks must be repeated after any servicing or fault finding.

3. Ensure all external controls are calling for heat and check all external and internal fuses. Before any servicing or replacement of parts ensure the gas and electrical supplies are isolated.

Refer to Section 13.0 “Illustrated Wiring Diagram” for position of numbered terminals Central Heating - Follow operational sequence

Turn selector to

neon illuminated

Primary flow switch

operated

Fan runs at max speed

Burner goes out

Turn temperature control

to max.

Pump runs

Air pressure

switch proved

neon flashing

Burner on neon

illuminated

Burner output

modulates until set

temperature is reached

Spark at ignition

electrodes for up to 10

seconds

Go to section ‘A’

neon flashing

Go to section ‘B’

neon flashing

Go to section ‘C’

Go to section ‘J’

neons flashing

Go to section ‘D’

neon flashing

Go to section ‘E’

Replace PCB

Turn selector to the reset position. If the neon does

not extinguish go to

sections ‘H’ & ‘K’

Go to section ‘F’

neon flashing

Go to section ‘I’

Go to section ‘G’

Fan stops Pump stops

Operation sequence

correct

neon flashing

Turn selector to reset

position. If regular resetting is required or appliance still does not operate investigation is

necessary

External controls calling

for heat

Ensure controls are set to

demand and verify the

contacts are closed

Burner extinguishes

after 10 seconds

YES

YES YES YES

NO NO

YES

NOTE: When instructed to turn the selector to the reset position turn the selector switch fully anticlockwise against the spring pressure to position R and hold for 2 seconds to reset the boiler.

Page 41

14.0 Fault Finding

Fault Finding Solutions Sections A to E

Is there 230V at:

Main terminals L and N Check electrical supply

Main terminal fuse

Replace fuse

Replace PCB

neon

illuminated

YES

Selector terminals a & b and a & 3. PCB - A4 connector terminals 4 & 5

Check wiring Replace selector

Pump Replace pump

PCB - A4 connector terminals 3 & 6

Replace PCB

Change pump supply cable

YES

CH system pressure 0.5 to 1.5 bar Re-pressurise system

Primary flow valve diaphragm damaged

Replace diaphragm

Flow valve rod obstructed

YES

Check the tap of the automatic air vent is opened

Open the automatic air vent

YES

Continuity across flow microswitch and PCB - A5 connector terminals 7 & 8

Replace microswitch

1. NO

Primary temperature sensor faulty. Cold resistance approx. 11K ohms (resistance reduces with increase in temp.)

Replace sensor

YES

Fan connections correct at fan. PCB - A2 connector, is 230V across terminals 5 & 7

Fan jammed or faulty winding

Replace PCB

Replace fan

YES

If pump jammed, release

Check and correct if necessary

1. Electrical and pressure tube connections

2. Blockage of pressure tubes

3. Restriction in flue

4. Venturi

Replace air pressure switch

Gas at burner

Ensure gas is on and purged

Replace PCB

Replace gas valve

neon flashing

PCB - A1 connector has 230V AC

across terminals 2 & 4

YES

Turn selector switch

to reset position

YES

Page 42

14.0 Fault Finding

Replace PCB

Check and correct if necessary

1. Ignition electrode and lead

2. Electrode connection

3. Spark gap and position

230V at PCB - A1 connector across terminals 3 & 5. Check wiring

YES

Replace igniter

YES

Check the burner setting pressure of

the gas valve

(see Section 9.2 of Commissioning)

Voltage at modulating coil of gas valve is: Max. burner press.approx 9V DC (13V DC LPG) Min. burner press.approx 1V DC

Current at modulating coil of gas valve is: (Use an instrument with average function for this measure) 30 ÷ 230 mA DC (45 ÷ 310 mA DC LPG)

Replace gas valve

Replace PCB

Check and correct if necessary

1. Flame sensing electrode and lead connections

2. Electrode position

Flame current should be 1 µA approx.

Replace PCB

Replace

PCB

YES

Replace flame sensing electrode

YES

Ensure that mains input

terminal L is Live (230V) and

N is Neutral (0V)

Check terminal 1 of On/Off/Reset selector is in connection with PCB - A4 connector terminal 2

Check electrical continuity across terminals 1 & a

of On/Off/Reset selector when turned to position

Replace On/Off/Reset selector

Replace PCB

YES

Replace safety

thermostat

YES

Overheat thermostat operated

or faulty, i.e. continuity across

thermostat terminals

Allow to cool. Continuity

across thermostat terminals

more than 1.5 ohm

Page 43

15.0 Short Parts List

Short Parts List

Key G.C. Description Manufacturers No. No. Part No.

22 E66 383 Fan 35/60 248001

E66 527 Fan 60/100 248002

23 393 374 Pressure Switch 247380

32 E66 393 Heat Exchanger 35/60 248016

E66 535 Heat Exchanger 60/100 248017

41 E66 398 Burner 35/60 248029

E66 399 Burner 60/100 248030

44 Injector 248210

59 E66 408 Electrode Lead 248037

63 E66 411 Spark or Sensing

Electrode 247384

72 E66 431 Pump 35/60 248041

E66 539 Pump 60/100 248042

102 Hydraulic Outlet Assy 248490

131 342 571 Temperature Sensor 247394

135 E66 439 Safety Thermostat 248079

140 Gas Valve 5107339

154 PCB 248074

156 DHW Relay PCB 248620

169 E66 453 Pressure Gauge 248090

528 Return Heating 248497

Temperature Sensor

140

102

135

154

169

131

528

35/60 models

60/100 models

156

Page 44

Baxi UK Limited

Brownedge Road

Bamber Bridge Preston

Lancashire

PR5 6SN

www.baxi.com

After Sales Service

08706 096 096

Technical Enquiries

08706 049 049

Comp No248544 - Iss 5 - 7/02

922.553.1