Alpha 280, 240 Installation and Servicing Instructions
Installation and Servicing
Instructions
Alpha 240/280
Range of Wall Mounted, Fan Assisted, Room Sealed,
Gas Fired Combination Boilers
For Technical help or for Service call ...
ALPHA HELPLINE
Tel: 0870 3001964
Nepicar House, London Road,
Wrotham Heath, Sevenoaks,
Kent TN15 7RS
Service Listed
Alpha 240P G.C. No. 47 532 09
0051
Leave these instructions with the User
Alpha 240E G.C. No. 47 532 06
Alpha 280E G.C. No. 47 532 08
Alpha 280P G.C. No. 47 532 12
For use with Natural Gas only
CONTENTS
1 Introduction ....................................... 2
2 Technical data...................................3
3 General boiler information..................7
4 Installation......................................... 11
5 Commissioning ................................. 16
6 Boiler operation ................................. 18
7 Routine servicing...............................19
8 Component replacement ................... 21
9 Wiring diagrams ................................ 34
10 Fault finding ...................................... 38
11 Short parts list ................................... 43
12 Service history .................................. 44
1 INTRODUCTION
The Alpha Range of boilers are wall mounted, fan assisted room-sealed combination boilers. Heat output is controlled by a
modulating gas valve.
The boilers, providing both central heating and domestic hot water at mains pressure, are designed for use with a fully
pumped, sealed and pressurised heating system using only Natural Gas.
The boilers are supplied with a pump, diverter valve, pressure relief valve, expansion vessel and pressure gauge fully
assembled and tested.
As supplied, the Alpha 240E and 240P boilers will automatically modulate to provide central heating outputs between 9.3 and
23.3 kW (31 700 and 79 500 Btu/h). The Alpha 280E and 280P boilers will provide central heating outputs between 9.3 and
28.0 kW (31 700 and 95 500 Btu/h).
The maximum output available for domestic hot water is 23.3 kW (79 500 Btu/h), capable of providing 9.5 litres/min with a
temperature rise of 35°C for the Alpha 240E and 240P boilers, and 28.0 kW (95 500 Btu/h), capable of providing 11.4 litres/min
with a temperature rise of 35°C for the Alpha 280E and 280P boilers.
IMPORTANT
It is the law that all gas appliances are installed by a competent person, ie CORGI registered personnel, in accordance with
the following recommendations:-
Gas Safety (Installation and Use) Regulations
All relevant Building Regulations issued by the Department of the Environment
Building Standards (Scotland) (Consolidation) Regulations issued by the Scottish Development Department
Local Water Bye Laws
Health & Safety Document No. 635 (The Electricity At Work Regulations 1989)
The installation should also be in accordance with the following British Standard Codes of Practice:BS 5440:1:1990 Flues
BS 5449:1990 Forced circulation hot water systems
BS 5546:1990 Installation of hot water supplies for domestic purposes
BS 6700:1987 Design, installation, testing and maintenance of services supplying water
BS 6798:1987 Installation of gas fired hot water boilers
BS 6891:1989 Gas installation
BS 7593:1992 Code of Practice for treatment of water in heating systems
BS 7671:1992 Requirements for electrical installations, IEE Wiring Regulations
If installation is in a timber framed building, refer to the British Gas publication 'Guide for Gas Installations in Timber Frame
Housing' reference DM2.
This appliance meets the requirements of IP44, ie degree of protection against moisture.
Failure to install this appliance correctly could lead to prosecution. It is in your own interest and that of safety to ensure that the
law is complied with.
Manufacturer's instructions must NOT be taken in anyway as over-riding statutory obligations.
Note: Ensure that the Benchmark Log Book has been completed after the boiler has been installed and commissioned.
Alpha 240/280 - Contents/Introduction
2
2 TECHNICAL DATA
2.1 PERFORMANCE - NATURAL GAS
Alpha 240E and 240P Alpha 280E and 280P
Central Heating
Heat Input kW
(Gross) Btu/h
Heat Output (modulating) kW
Btu/h
Burner Pressure mbar
Settings in wg
Room sealed chamber
panel fitted
Room sealed chamber
panel removed
mbar
in wg
Gas Rate m³/h
ft³/h
MAX.
28.63
97 700
23.3
79 500
9.6
3.84
10.6
4.24
2.74
96.76
Alpha 240E and 240P Alpha 280E and 280P
Domestic Hot Water
Heat Input kW
(Gross) Btu/h
Output to Water (modulating) kW
Btu/h
Burner Pressure mbar
Settings in wg
Room sealed chamber
panel fitted
Room sealed chamber
panel removed
mbar
in wg
Gas Rate m³/h
ft³/h
Flow Rate at 35°C Rise L/min
G.P.M.
MAX.
28.63
97 700
23.3
79 500
9.6
3.84
10.6
4.24
2.74
96.76
9.5
2.1
MIN.
11.76
40 150
9.3
31 700
1.1
0.44
2.1
0.84
1.13
39.9
MIN.
11.76
40 150
9.3
31 700
1.1
0.44
2.1
0.84
1.13
39.9
Central Heating
Heat Input kW
(Gross) Btu/h
Heat Output (modulating) kW
Burner Pressure mbar
Settings in wg
Room sealed chamber
panel fitted
Room sealed chamber
panel removed
Gas Rate m³/h
Domestic Hot Water
Heat Input kW
(Gross) Btu/h
Output to Water (modulating) kW
Burner Pressure mbar
Settings in wg
Room sealed chamber
panel fitted
Room sealed chamber
panel removed
Gas Rate m³/h
Flow Rate at 35°C Rise L/min
Btu/h
mbar
in wg
ft³/h
Btu/h
mbar
in wg
ft³/h
G.P.M.
MAX.
34.5
117 700
28.0
95 500
11.8
4.7
12.5
5.0
3.25
114.8
MAX.
34.5
117 700
28.0
95 500
11.8
4.7
12.5
5.0
3.25
114.8
11.4
2.5
MIN.
11.76
40 150
9.3
31 700
1.5
0.6
1.9
0.76
1.13
39.9
MIN.
11.76
40 150
9.3
31 700
1.5
0.6
1.9
0.76
1.13
39.9
2.2 SYSTEM
Central Heating (Sealed System)
Max. Working System Pressure
Min. System Pressure
Max. System temperature
Pressure Relief Valve Setting
Expansion Vessel Size (pre-charge press.)
Flow Connection
Return Connection
Relief Valve Connection
Recommended System Pressure (cold)
CH Water Temp. (Approx. max.)
2.3 COMPONENTS
Burner (15 blade)
Main Heat exchanger
DHW Heat Exchanger
Main Burner Injectors 240E/P
280E/P
Pilot Injector 240P/280P
Flue - Outer Duct
Flue - Inner Duct
Stainless steel
Stainless Steel
Epoxy coated
2.5 bar
0.5 bar
82°C
3 bar (44 PSI)
8 L at 0.8 bar
22 mm
22 mm
15 mm
1.0 bar
82°C (180°F)
Copper
1.18 mm
1.25 mm
0.27 mm
Aluminium
Domestic Hot Water
Max. Mains Inlet Water Pressure
Min. Mains Water Pressure
Min. DHW Flow Rate
Mains Inlet Connection
DHW Outlet Connection
DHW Water Content 240E/P
280E/P
Outlet Water Temp. (Approx. max.)
2.4 INSTALLATION
Min. Clearances for Servicing Top
Bottom
Sides
Front
Flue Terminal Size
Flue Terminal Protruding
Hole Size Required For Flue Assy.
Lift Weight 240E/P
280E/P
8 bar
0.2 bar
2.5 l/min
15 mm
15 mm
0.20 L
0.23 L
62°C (144°F)
220 mm
250 mm
5 mm
450 mm
100 mm Dia.
115 mm
107 mm Dia.
39 kg
40 kg
Alpha 240/280 - Technical Data
3
2.5 GENERAL 2.6 ELECTRICAL
Dimensions Height
Width
Depth
Gas Connection
Primary Water Content 240E/P
280E/P
Air Duct Diameter
Flue Duct Diameter
900 mm
450 mm
360 mm
22 mm
1.7 L
1.9 L
100 mm
60 mm
Supply
External Fuse
Power Consumption
Internal Fuse
Electrode Spark Gap 240E/280E
240P/280P
Thermocouple (240P/280P only):min. closed circuit output
230/240 V ~ 50 Hz
2.7 FLUE LENGTHS
Flue length = 0.75 m (not including the terminal, which is supplied with the boiler)
Note: Additional flues (of the same length) are available.
Length of Flue Required:-
Rear Flue = wall thickness +150 mm
Side Flue = wall thickness + distance between wall and side of boiler + 185 mm
Vertical Flue = distance from top of boiler side panel to required roof position minus 1 m for vertical terminal assembly
Maximum flue length = 4 m
Each additional 90° Bend is equivalent to 1 m of flue length
Each 45° Bend is equivalent to 0.5 m of flue length
The Vertical Flue terminal assembly is equivalent to 1 m of flue length
3 A
170 W
F2 A
1.2 to 3.5 mm
5 mm
10 mV
2.8 AVAILABLE PUMP HEAD FOR CENTRAL HEATING
Output Available pump head
kW
23.3
17.58
14.65
11.63
9.3
Btu/h
79 500
60 000
50 000
40 000
31 700
17°C 20°C
metres
2.33
3.00
3.45
3.85
4.20
feet
7.7
9.8
11.3
12.6
13.8
metres
2.95
3.45
3.75
4.05
4.35
feet
9.7
11.3
12.3
13.3
14.3
litre/min
18.10
14.80
12.36
9.89
7.84
This information is based on 17°C and 20°C system design temperature difference.
Note: For outputs upto 28 kW refer to section 3.7.
Flow rate
17°C 20°C 17°C 20°C
gal/min
4.00
3.27
2.72
2.18
1.73
litre/min
15.10
12.60
10.50
8.40
6.70
2.9 ELECTRICAL CONNECTIONS
Note: This Appliance Must Be Earthed
An optional integral Clock kit is available if required.
Blue
Black
Wire
Brown
Wire
Wire
12345
Black
Not
Wire
Used
Internal Clock Terminals
WARNING
1. Ensure wires are connected
correctly
2. Only fit the Alpha recommended
clock. Other clocks could cause
damage.
gal/min
3.32
2.78
2.32
1.85
1.47
Pressure loss across boiler
metres
metres
2.50
2.20
2.00
1.70
1.45
feet
8.2
7.2
6.6
5.6
4.8
2.25
2.00
1.75
1.50
1.35
feet
7.4
6.6
5.7
4.9
4.4
Clock connections
Alpha 240/280 - Technical Data
4
Boiler terminal block
Fig. 1
2.10 BOILER SCHEMATIC - Alpha 240P and 280P
1 - Pressure gauge
2 - Gas service cock
3 - Mains inlet on/off valve and filter
4 - Diverter valve assy.
5 - DHW flow valve
6 - Primary flow valve
7 - Differential pressure sensor
8 - Automatic by-pass
9 - DHW heat exchanger
10 - DHW expansion device (if fitted)
11 - Drain point
12 - Pressure relief valve
13 - DHW flow valve microswitch
14 - Primary flow valve microswitch
15 - Pump and air separator
16 - Automatic air vent
17 - DHW temperature sensor
18 - Primary temperature sensor
19 - Overheat thermostat
20 - Expansion vessel
21 - Gas valve
22 - Main burner injector
23 - Main burner
24 - Pilot burner
25 - Thermocouple
26 - Main heat exchanger
27 - Flue hood
28 - Fan
29 - Air pressure switch
30 - Positive pressure point
31 - Negative pressure point
32 - Flue adaptor
33 - Flue sample point
34 - Room sealed chamber
35 - On/off valve
36 - On/off valve and filter
Heating
Flow
Domestic
Hot Water
Outlet
Gas Cold Mains
Water Inlet
Heating
Return
Fig. 2
Alpha 240/280 - Technical Data
5
2.11 BOILER SCHEMATIC - Alpha 240E and 280E
1 - Pressure gauge
2 - Gas service cock
3 - Mains inlet on/off valve and filter
4 - Diverter valve assy.
5 - DHW flow valve
6 - Primary flow valve
7 - Differential pressure sensor
8 - Automatic by-pass
9 - DHW heat exchanger
10 - DHW expansion device (if fitted)
11 - Drain point
12 - Pressure relief valve
13 - DHW flow valve microswitch
14 - Primary flow valve microswitch
15 - Pump and air separator
16 - Automatic air vent
17 - DHW temperature sensor
18 - Primary temperature sensor
19 - Overheat thermostat
20 - Expansion vessel
21 - Gas valve
22 - Main burner injector
23 - Main burner
24 - Ignition electrodes
25 - Flame sensing electrode
26 - Main heat exchanger
27 - Flue hood
28 - Fan
29 - Air pressure switch
30 - Positive pressure point
31 - Negative pressure point
32 - Flue adaptor
33 - Flue sample point
34 - Room sealed chamber
35 - On/off valve
36 - On/off valve and filter
Heating
Flow
Alpha 240/280 - Technical Data
6
Domestic
Hot Water
Outlet
Gas Cold Mains
Water Inlet
Heating
Return
Fig. 3
3 GENERAL BOILER INFORMATION
3.1 GAS SUPPLY
The Alpha 240E and 240P boilers require a gas rate of 2.74 m³/h (96.76 ft³/h) and the Alpha 280E and 280P a gas rate of
3.25 m³/h (114.8 ft³/h).
The meter and supply pipes must be capable of delivering this quantity of gas in addition to the demand from any other
appliances in the house. The boiler requires at least a 22 mm gas supply pipe.
The complete installation, including the meter, must be tested for gas soundness and purged as described in BS 6891.
3.2 ELECTRICAL SUPPLY
The boiler requires a 230/240 V ~ 50 Hz mains supply, fused at 3 A
The boiler must be earthed.
There must only be one common isolator, providing complete electrical isolation, for the boiler and any external controls.
Using PVC insulated cable not less than 0.75 mm² (24 x 0.2 mm) to BS 6500 Table 16, the boiler should be connected to a
fused three pin plug and unswitched shuttered socket outlet (both complying with BS 1363), or a fused double pole switch with
a contact separation of at least 3 mm in both poles.
Wiring external to the boiler must be in accordance with the current IEE Wiring Regulations (BS 7671).
Note: If a room thermostat is fitted, it must be suitable for 230/240 V switching.
3.3 AIR SUPPLY
The boiler does not require any air vents for cooling in the room in which it is installed or when installed in a cupboard or
compartment. The minimum clearances for servicing must always be maintained.
Note: A cupboard or compartment used to enclose the boiler must be designed and constructed specifically for the purpose,
i.e. comply with the Building Regulations.
3.4 FLUE SYSTEM - Fig. 4
The flue system must be installed in accordance with BS 5440:1.
The flue assembly supplied for the boiler is 0.75 m in length.
For horizontal flues ensure there is a slight downward slope towards the terminal.
Additional flue components are available as follows:-
0.75 m flue
90° bend
45° bend
Vertical flue terminal assembly. Refer to the separate installation instructions supplied with the assembly.
A Twin Pipe Flue system and an Easy Flue system are available for use with all the boilers in the range. Refer to the separate
instructions for details.
Also, available for use with the Alpha 240E and 240P only is a Low Easy Flue system. Refer to the separate instructions for
details.
The following methods determine the correct length of flue required.
For rear exit flue L = B + 150 mm
For side exit flue L = B + C + 185 mm (min. side clearance required is 5 mm)
For vertical flue L = H minus 1000 mm for vertical terminal assembly
Where L = Required flue length
B = Finished wall thickness
C = Distance from the inside wall to the side of the boiler
H = Distance from top of boiler side panel to roof position
Note: 1. If an extra 90° bend is used, this reduces the maximum flue length by 1 m. Each 45° bend used reduces the maximum
flue length by 500 mm.
2. Under no circumstances must the flue length (including allowances for extra bends) exceed 4 metres.
3. Failure to use Alpha flue components with the boiler will invalidate the boilers CE approval, warranty and may be unsafe.
Alpha 240/280 - General Boiler Information
7
HORIZONTAL FLUE OPTIONS - Lmax = 4 metres
L = B + C + 185 mm
C
B
B
F
E
L = B + E + F + 185 mm + (90° bend = 1 metre)
L = B + C + E + 185 mm
C
B
E
C
B
VERTICAL FLUE OPTIONS
HH
Not less than
300 mm
Not less than
450 mm
L = B + C + 185 mm + (2 x 45° bends = 1 metre)
Hmax = 3 metresHmax = 4 metres
Not less than
450 mm
Not less than
300 mm
Alpha 240/280 - General Boiler Information
8
Fig. 4
3.5 FLUE TERMINAL LOCATION - Fig. 5
Fig. 5
Terminal position
A Directly below an opening, air brick, windows, etc.
B Below gutters, soil pipes or drain pipes
C Below eaves
D Below balconies or car port roof
E From a vertical drain pipe or soil pipe
F From an internal or external corner
G Above ground, roof or balcony level
H From a surface facing the terminal
I From a terminal facing the terminal
J From an opening in the car port (e.g. door, window) into dwelling
K Vertically from a terminal on the same wall
L Horizontally from a terminal on the same wall
The flue terminal must be exposed to the external air and the position must allow the free passage of air across it at all times.
In certain weather conditions the terminal may emit a plume of steam. Avoid positioning the terminal where this may cause a nuisance.
If the terminal is fitted within 850 mm of a plastic or painted gutter or 450 mm of painted eaves or 300 mm of a plastic car port
roof, an aluminium shield at least 1 m long should be fitted to the underside of the gutter or painted surface. If the terminal is
fitted less than 2 m above a surface to which people have access, the terminal must be protected by a terminal guard.
A suitable guard (type K3 - G.C. No. 393 554) is available from:
Tower Flue Components Ltd., Vale Rise, Tonbridge, Kent TN9 1TB
Min. distance
300 mm
75 mm
25 mm
25 mm
25 mm
25 mm
300 mm
600 mm
1200 mm
1200 mm
1500 mm
300 mm
3.6 BOILER LOCATION
The boiler is not suitable for external installation.
The boiler must be installed on a flat vertical wall which is capable of supporting the weight of the boiler.
If the boiler is to be fitted in a timber framed building, it should be fitted in accordance with the British Gas publication 'Guide for
Gas Installations in Timber Frame Housing', reference DM2.
The boiler may be installed in any room or internal space, although particular attention is drawn to the requirements of the current IEE Wiring
Regulations, and in Scotland, the electrical provisions of the Building Regulations applicable in Scotland, with respect to the installation of
the boiler in a room or internal space containing a bath or shower. Where a room-sealed boiler is installed in a room containing a bath or
shower, it must not be possible for a person using the bath or shower to touch any electrical switch or boiler control utilising mains electricity.
The boiler may be installed in a cupboard or compartment, provided it is correctly designed for that purpose, i.e. complies with
the Building Regulations and the requirements of BS 6798.
Alpha 240/280 - General Boiler Information
9
3.7 CENTRAL HEATING SYSTEM - Fig. 6
The boiler is designed for use in a sealed central heating system in accordance with the requirements of BS 5449 and BS 6798.
The system should be designed to operate with flow temperatures of up to 82°C. When designing the system, the pump head, expansion
vessel size, mean radiator temperature, etc must all be taken into account. Refer to the pump performance table for guidelines.
System volume - The expansion vessel incorporated into the boiler is suitable for a sealed heating system with a maximum
water content of 80 litres (18 gal). For guidance on water contents contact Alpha Therm Ltd. for Technical Data Sheet 15.
Above 80 litres, consideration should be given to fitting an additional expansion vessel fitted in the position shown in Fig. 6. To
check correct operation of the expansion vessel(s) the system pressure should not be more than 2.5 bar when the system is at
maximum operating temperature (for further guidance refer to BS 7074:1).
The boiler is supplied with the following components built in:Pressure relief valve - complying with BS 6759 and set to operate at 3 bar. The discharge pipe must be routed clear of the
boiler to a drain, in such a manner that it can be seen, but cannot cause injury to persons or property.
Pressure gauge - To indicate the system pressure to be maintained.
Expansion vessel - Conforming to BS 4814 with a capacity of 8 litres and pre-charged to a pressure of 0.8 bar.
By-pass - Where all radiators are fitted with thermostatic radiator valves an external by-pass may be required.
Make up vessel
Static head of system
Boiler
casing
Automatic
air vent
Additional expansion
vessel (if required)
Double check valve assy.
Heating
by-pass
(If required)
By-pass could be a 15 mm pipe controlled
by a valve or an uncontrolled radiator.
Heating flow
Filling point
DHW outlet
Mains water inlet
Note: If the mains is fitted with water
meter, check valves or loose jumper stop
cock, then a DHW expansion device must
be fitted.
Note: A drain tap should be installed at the lowest
point of the heating circuit and beneath the appliance.
Heating return
System
drain tap
Fig. 6
3.8 FILLING THE CENTRAL HEATING SYSTEM - Figs. 7, 8
The system design pressure (cold) should be set to 1.0 bar. This pressure is equivalent to a static head (see Fig. 6) of 10.2 metres of water.
Provision should be made to replace water lost from the system. This can be by manual or automatic means, as shown in Figs.
7 and 8. The position for connecting an automatic make-up vessel is indicated in Fig. 6. A double check valve assembly must
be used, as shown in Fig. 8.
Filling of the system must be carried out in a manner approved by the local Water Undertaking. Where allowed, the system may
be filled via a temporary connection as shown in Fig. 7. After filling, always disconnect the flexible hose of the filling loop.
All fittings used in the system must be able to withstand pressures up to 3 bar.
Drain taps (to BS 2879) must be used to allow the system to be completely drained.
The heating system should be thoroughly flushed before the boiler is connected and again after the first heating.
If it is required to add inhibitor to the system, refer to Alpha Therm Ltd. for guidance.
Refer to BS 5449 and BS 6798 for further information.
Air inlet
valve
Double check
Heating circuit
return
valve assembly
Stop
valve
Test cock
temporarily connected
Fig. 7 Fig. 8
Alpha 240/280 - General Boiler Information
10
Hose
unions
Filling loop
Mains
water
supply
Heating circuit
return
Double check
valve assembly
Test cock
Overflow
Stop
valve
Mains
water
supply
Feed cistern to be
located above highest
point in the system
3.9 DOMESTIC HOT WATER SYSTEM
The minimum flow rate needed for the flow switch and burner to operate is 2.5 litres/min.
The incoming mains water pressure should be between 0.2 and 8 bar to ensure efficient operation. If the pressure is above 7 bar
a pressure reducing valve must be fitted.
To ensure economic use, the pipe runs between the boiler and taps should be in 15 mm copper pipe and be as short as
possible. Where possible the pipework should be insulated to reduce heat loss.
All taps and mixing valves used with the hot water system must be suitable for operating at a mains pressure of up to 8 bar.
Showers - A shower may be used with the boiler if required.
If a loose or flexible head type shower is used it may require the fitting of a double check valve, to comply with Water Bye Law 17.
Bidets - No anti-syphonage arrangements are necessary, provided the outlets are shrouded and it is not possible to attach a
temporary hand held spray. A supply of direct mains fed hot and cold water is permitted provided the appliance is of the overrim flushing type.
Before the mains water supply pipe is connected to the boiler, it should be thoroughly flushed out to avoid the danger of dirt or
foreign matter entering the boiler.
The mains water supply connection to the boiler must be the first connection from the mains supply.
Note: The boiler has been provided with the facility for fitting an expansion device, i.e. shock arrestor or expansion vessel in
the DHW circuit (see Fig. 35). An optional kit is available from Alpha Therm Ltd., Goldsel Road, Swanley, Kent BR8 8EX.
If the mains water supply has been fitted with check valves, water meter or a loose jumper stop cock, then an expansion device
must be fitted.
4 INSTALLATION
4.1 UNPACKING
1. The boxes required when the boiler is installed with a horizontal flue are as follows:Box 1 Cased boiler
Water and gas valves plus washers
Water fittings and filling loop
Mounting bracket plus screws and wall plugs
Flue terminal and flue sealing collar plus 2 screws
Literature pack and Wall template
Box 2 90° flue bend with clamp (not required for vertical flue)
Box 3 0.75 m flue (for side and rear flue) with two clamps and inner duct support
2. Unpack boiler and remove loose items packs.
3. Remove the two screws at the top of the front casing. Slide it up and lift it off.
4.2 CLEARANCES REQUIRED - Fig. 9
360 mm
5 mm
900 mm
220 mm
450 mm
Minimum
clearances
5 mm
Minimum
clearance
of 450 mm
from front
of boiler
250 mm
Fig. 9
Alpha 240/280 - General Boiler Information/Installation
11
4.3 PREPARE THE WALL - Figs. 10, 10A
1. Decide upon the position of the boiler taking into account the
clearances required for servicing and the flue terminal position.
Rear exit hole
110 mm dia.
Ensure line is level
190 mm
2. Tape the template to the wall (ensure it is level and the right
way up) and mark the position of the holes for the boiler
mounting bracket and bottom fixings. If rear exit flue is used,
mark the position of the hole for the flue.
Note: If pipework is routed at the rear of the boiler (top pipe
connections), mark the four fixing holes shown in Fig. 10A.
3. Side exit flue - Continue the horizontal centre line of the flue
across the wall to the side wall, then along the side wall 190 mm
(ensure the lines are horizontal). This will give the position of the
centre of the hole for the flue.
4. Cut the 110 mm diameter hole (or use a 107 mm core drill) in
135 mm
Top
fixing
holes
Position of
110 mm hole
to be cut for
side exit flue
Wall mounting
bracket
the wall for the flue.
Note: For internal fitting of the flue, using the flue sealing collar
supplied, cut a 127 mm dia. flue hole using a 127 mm core drill.
5. Drill the fixing holes (8 mm dia.) to accept the No.10 plugs
supplied. Using the washers supplied with the screws, fit the
mounting bracket.
Note: When pipework is routed at the rear of the boiler, i.e. top pipe
Boiler
outline
Template
Fig. 10
Bottom
fixing holes
connections the mounting bracket is not used. (Refer to fig. 10A). Fit the top fixing screws, leaving just enough protruding, to
hang the boiler on.
6. Top pipe connections - Remove the mounting cross bar from the rear of the boiler and fit it to the top as shown in Fig. 10A.
Mounting
cross bar
Top fixing holes
Note: Preform the
Position for
15 mm and 22 mm
pipework
Bottom
fixing holes
35 60 3560
pipework at the back
of the boiler before
hanging the boiler
Fig. 10A
4.4 FIT THE BOILER - Refer to Fig. 10
1. Lift the boiler and locate it on the mounting bracket or the top fixing screws when piping from above.
2. Adjust the position of the boiler, as necessary. Fit the bottom screws to secure the boiler in position (do not forget to
tighten the top screws when piping from above).
4.5 CONNECT THE PIPEWORK - Fig. 11
1. Thoroughly flush out all the water pipework.
Note: Ensure that all the plastic caps are removed from the boiler connections.
2. Secure all the valves/fittings to the boiler- use the washers supplied, ensuring they are facing the rear wall. Fit the union
bends to the valves.
Note: 1. If soldering to the boiler union bends, ensure the bends are not connected to the valves, otherwise the internal
seals may be damaged.
2. Ensure the 22 mm isolating valve with the filter is fitted to the heating return connection. (Refer to Fig. 11).
3. Fit the pressure relief valve connection before the isolating valves.
3. Connect the system pipework to the boiler.
Note: Do not forget that the pressure relief valve discharge pipe must be routed clear of the boiler to a drain in such a
manner that it may be seen, but cannot cause injury to persons or property.
4. Ensure that all the valves are closed (spindle flats at right angles to valve) and do not turn on the water or gas supplies at this stage.
Alpha 240/280 - Installation
12
Note: Disconnect the filling loop after
filling the central heating system.
A - Heating flow (22 mm)
B - Hot water outlet (15 mm)
C - Gas inlet (22 mm)
D - Cold water mains inlet (15 mm)
E - Heating return (22 mm)
F - Pressure relief valve (15 mm)
Note: Both Heating return and Cold water
mains inlet valves contain serviceable filters.
Filling loop
20 23
95 65 65 65 65 55
ABCDEF
Fig. 11
4.6 FIT THE FLUE - Figs. 12, 13
1. The following procedure applies to both rear or side exit flue. The only difference being the lengths to which the ducts are cut.
Rear flue Outer air duct length = finished wall thickness + 110 mm.
Inner flue duct length = finished wall thickness + 147 mm.
Side flue Outer air duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + 145 mm.
Inner flue duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + 182 mm.
2. If the overall length of the inner duct is greater than 750 mm then a flue extension is required. To fit an extension refer to
the following section.
3. Withdraw the inner flue duct from the outer air duct.
4. Mark the outer air duct to match the length given above, measure from the end of the tube as shown in Figs. 12 and 13.
5. Mark the inner flue duct to match the length given above.
6. Cut both the inner and outer ducts to length.
Note: Do not cut the outer duct end with the two holes, these are for securing the terminal.
Ensure that all cuts are square and burr free.
7. Fit the flue terminal to the outer duct by inserting it into the end with two holes. Align the holes and secure with the two
screws provided.
8. Place the inner flue duct back into the outer duct.
9. Pass the flue assembly through the wall (from inside or outside).
Note: Internal fitting - If there is no access to make good the outside wall, locate and secure the flue sealing collar onto
the outer duct of the flue immediately before the terminal. Push the flue assembly through the 127 mm flue hole, so that
the collar completely passes through the wall. Then pull the flue assembly back into the correct position. Visually check
that the collar is sealing the outside wall and that it is not restricting any of the openings of the flue terminal.
10. Position the seal and clamp (two screws), supplied with the bend, over the boiler flue adaptor. Fit the bend and rotate to
the correct position, then secure in position. See Fig 12.
Note: Ensure that the seal is located over both the bend and the flue adaptor.
11. Place the inner (no seal) duct clamp in position over the bend outlet as shown in Figs. 12 and 13, and position the outer
duct seal over the bend.
12. Push the outer duct into the wall slightly at the same time as pulling the inner duct towards the bend, inserting it fully into
the clamp on the bend. Tighten the clamp to secure the inner duct.
Note: Ensure the inner duct clamp screwed joint is at the bottom.
13. Pull the outer duct towards the bend. Check that the flue terminal protrudes 120 mm out of the wall, then position the seal
equally over the joint between the bend and the outer duct. Dismantle the clamp, position it over the seal and secure in
position.
14. Make good the inside and outside walls. The flue sealing collar could be used for making good either the outside or inside
by locating it over the outer duct of the flue and pushing it tight against the wall. If fitting the collar externally, ensure it does
not restrict any of the openings of the flue terminal.
Alpha 240/280 - Installation
13
120
Inner flue duct length
Outer air duct length
20
120
77
Terminal
Flue sealing collar
Note: For horizontal flue ensure there
is a slight downward slope
towards terminal.
20
90
190
Outer duct clamp and seal
Inner duct clamp
90° bend
Ensure joint of inner
Boiler
clamp is at bottom
Fig. 12 - Rear flue
Outer duct clamp
and seal
77
20
Seal
Inner duct clamp
125
20
Bend clamp
and seal
Restrictor
(N/A to 280E/P)
Screw
20
36
Boiler
225
Outer air duct length
Inner flue duct length
225
Fig. 13 - Side flue
4.7 FIT A FLUE EXTENSION - Figs. 12, 13
Note: 1. The maximum flue assembly length must not exceed a length of 4 metres.
2. If the flue is more than 1 m, the restrictor must be removed from the flue adaptor (see Fig. 13), by removing the screw
and lifting out the restrictor. The Alpha 280E and 280P are not fitted with a restrictor.
1. Withdraw the inner flue duct from the outer air duct supplied with the boiler.
2. Withdraw the inner flue duct from the extension. Secure the two ducts together using the clamp supplied with the
extension, ensure that the ducts are butted together and the clamp is central over the joint.
3. Secure the outer ducts together using the silicone seal and clamp supplied with the extension. Lubricating the silicone
seal with a soap solution will aid assembly.
4. With all the ducts assembled together, cut to the following lengths:Rear flue Outer air duct length = finished wall thickness + 110 mm.
Inner flue duct length = finished wall thickness + 147 mm.
Side flue Outer air duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + 145 mm.
Inner flue duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + 182 mm.
5. When measuring the outer duct, measure from the end of the tube as shown in Figs. 12 and 13.
6. Cut both the inner and outer ducts to length.
Note: Do not cut the outer duct end with the two holes, these are for securing the terminal.
Ensure that all cuts are square and burr free.
7. Fit the flue terminal to the outer duct by inserting it into the end with two holes. Align the holes and secure with the two
screws provided.
Alpha 240/280 - Installation
14
Loading...