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221756A
Important Note
The boiler is fitted with a Flue Blockage Safety Device, which
will shut down the boiler if there is an unacceptable spillage of
products at the draught diverter.
This safety device MUST NOT under any circumstances be
interferredwithorputoutofaction.Thesafetydevicemustonly
be replaced with the Glow-worm parts.
3.1 Flue
The integral draught diverter on the Hideaway range of boilers
makesthecombustionperformanceindependentofconditions
inthesecondaryflue,butincommonwithotherfuelsanefficient
flue is necessary to make sure of a trouble free installation.
The flue must be at least equivalent to 1m vertical.
The boiler flue socket is designed to take flue pipes to the
currentissueofBS567. If afluepipetoBS715 istobeused,an
adapter must be fitted to the boiler flue socket, as diagram 1.1.
The flue must be in accordance with the current issue of
BS5440 Part 1.
3.2 Flue Guidelines
Theflueshould bekeptasshort aspossible. Horizontalorvery
shallow runs of the flue should be avoided as they encourage
local cooling.
Alwayschooseaflueroute which willcausetheleastcoolingof
the flue.
There should be a vertical rise of at least 600mm (2ft) before
using a bend. 90oelbows should not be used.
End with a certificated flue terminal, preferably above ridge
height, but at least above the eaves of a pitched roof.
An existing chimney must be thoroughly swept and all debris
cleared away before lining.
3.3 Timber Frame Buildings
If the boiler is to be installed in a timber frame building it should
be fitted in accordance with the Institute of Gas Engineers
documentIGE/UP/7/1998. Ifindoubtseekadvicefromthelocal
gas undertaking or Hepworth Heating Ltd.
3.4 Ventilation for Boiler Installed in a Room
or Space
If the boiler is to be installed in a room or space a purpose
designed permanent ventilation opening, to supply air for
combustion,mustbeprovidedonanoutsidewalltoexternalair,
refer to the current issue of BS5440 Part 2 for details.
The opening may be directly into the room or the space
containing the boiler, or an outside wall of an adjacent room or
space which has an internal permanent air vent, of the same
size, into the room or space containing the boiler.
Do not ventilate through a bedroom, bedsitting room, private
garage or a room containing a bath or shower.
When the boiler is installed in a room or internal space already
containing other fuel burning appliances then the air supply of
such appliances must be taken into account.
The ventilation opening areas are given in “Air Vent Table A”.
The figures quoted refer to the minimum acceptable effective
area.
3 Flue and Ventilation
3.5 Ventilation for Boilers Installed in a
Cupboard or Compartment
Whentheboilerisfittedinacupboardorcompartment,highand
low level purpose designed, permanent openings must be
provided to supply air for combustion and compartment
ventilation.
The air vents must have minimum areas in accordance with
“Compartment Air Vent B”. The figures quoted refer to the
minimum acceptable effective area.
Both the high and low level openings must communicate with
thesameroom,ormustbothbeonthesamewalltooutsideair.
If air vent grilles are fitted to a cavity wall, the opening through
the wall must be ducted.
Whereventilationair to a compartment istaken from a room or
space, then the room or space must be fitted with a ventilation
opening as specified in “Air Vent Table A”.
For information regarding compartment requirements refer to
the appropriate section of the current issue of BS6798.
3.6 Extract Fans
Ifanextractfanisfittedinthepremises,thereisapossibilitythat
if adequate inlet openings are not provided, spillage of the
products from the boiler could occur.
When openings are fitted in accordance with the current issue
ofBS5440Part2andthissection,extractfansshouldnotcause
down draught, but where such fan installations are found, a
spillage test must be carried out in accordance with the current
issue of BS5440 Part 1 and any corrective work done.
FROM
OUTSIDE
COMPARTMENT AIR VENT TABLE 'B'
COMPARTMENT
VENTILATION
REQUIREMENTS
272cm242in2544cm284in2
136cm221in2272cm242in2
VENTILATION
FROM ROOM
OR SPACE
HIGH LEVEL LOW LEVEL
VENT AREA VENT AREA
AIR VENT TABLE 'A' FOR
ROOM/SPACE INSTALLATIONS
EFFECTIVE
AREA OF VENT cm2
in2104
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