5
FW468SE 27-06-13
Flue Draught
A flue draught of minimum 1.2mm to a maximum 2.5mm water gauge (12 to 25 Pascals) is required for
satisfactory appliance performance. The flue draught should be checked under fire at high output and, if it
exceeds the recommended maximum, a draught stabiliser must be fitted so that the rate of burning can be
controlled to prevent over-firing.
Connection to the Chimney
This appliance is
not
suitable for use in a shared flue. This appliance requires a direct flue connection to the
spigot. If practical, an existing fireplace opening can be bricked up or sealed with a register plate and a short
length of flue pipe of a minimum 150mm internal diameter may then be used to connect the stove to the
register plate in the chimney. This flue pipe should conform to Building Regulations. The stove must be
insulated and properly fitted into the fireplace opening by back filling with 6:1 ratio vermiculite & cement
mixture using minimal water through the top of the fireplace or flue spigot opening. The surface should be
finished using 1:1:8 mix of cement, lime and sand. The connecting pipe is fitted with the spigot pushed up
from
inside
the stove and rotated onto its keyhole slots to join to the pipe. Ensure that the pipe end is no
closer than 76mm to the side or rear chimney walls.
If necessary a hole must be opened up into the flue way above the fireplace in order to fit the appliance to
the flue correctly. Please consult HETAS recommended fitting methods if in doubt. It is
essential
that all
connections between the stove and chimney-flue are sealed and made airtight with sealing rope, clamping
rings and/or fire cement or heat resisting cement where required.
Both the chimney and flue pipe must be accessible for cleaning and if ANY parts of the chimney cannot be
reached through the stove (with baffle removed), a soot door must be fitted in a suitable position to enable
this to be done.
In adverse weather conditions, downdrafts may occur causing smoke or fumes to spill into the room. If this
occurs the appliance should be shut down as much as possible by closing the air controls and the room
should be ventilated to clear the fumes. If the problem persists seek the advice of a chimney sweep.
Material Clearances
Safety Distances from Combustible Surfaces:
Model
Side
Rear
FW4SE
500mm
700mm
FW6SE
400mm
400mm
FW8SE
500mm
500mm
In addition it is strongly recommended that any furniture or other combustible materials are kept at least
900mm clear from the front of the stove.
Distances from NON-combustible materials:
The stove can be recessed in a suitable sized non-combustible fireplace but a permanent free air gap of at
least 50mm must be left around the sides and top of the stove to obtain reasonable heat output and for access
to the stove for removal and maintenance. A clearance of 150mm will give a better heat output
To conform with building regulations the fireplace recess walls should be at least 200mm thick or each rear
leaf at least 100mm thick in the case of a cavity wall at the rear. If these dimensions are not met further
protection for any combustible materials must be provided. The walls of the fireplace recess and the hearth
must be made of non-combustible material.
Hearths:
Firewarm stoves require a 125mm thick non-combustible constructional hearth beneath them to protect the
building, this can include any solid non-combustible floor. A non-combustible superimposed hearth forming
