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3.1
GAS SUPPLY
The boiler requires 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 240 V switching
3.3
AIR SUPPLY
The boiler does not require any air vents in the room in which it is installed. If the boiler is installed in a cupboard or
compartment, permanent air vents are required in the cupboard or compartment at high and low levels. The vents must
communicate with the same room or be direct to outside air on the same wall.
If the boiler is installed in a cupboard or compartment with a door, allow at least 75 mm clearance between the front of the
boiler and the door for air movement.
3.4
FLUE SYSTEM - Fig. 3
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 the boiler. Refer to the separate instructions for
details.
The following methods determine the correct length of flue required.
For rear exit flue L = B + 115 mm
For side exit flue L = B + C + X mm (L/H side X = 380, R/H side X = 130).
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
Notes: 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. Minimum side clearance required is L/H side 20 mm, R/H side 5 mm.
3. Under no circumstances must the flue length (including allowances for extra bends) exceed the maximum
recommended length.
4. Failure to use Alpha flue components with the boiler will invalidate the boilers CE approval, warranty and may be
unsafe.
3
GENERAL BOILER INFORMATION
Position of vent
High
Low
Air from room/internal space
310 cm² (48 in²)
310 cm² (48 in²)
Air direct from outside
155 cm² (24 in²)
155 cm² (24 in²)
Alpha 500E - General Boiler Information
