Specifications

Hercules Boiler Model 4
Additional Air A permanent air entry opening or openings with a total
free area of at least 550mm
2
per Kw of appliance rated
output above 5Kw. If a flue draught stabiliser is used,
extra ventilation will be required.
There must not be an extractor fan fitted in the same room as the stove as
this can cause the stove to emit fumes into the room.
Hearth And Clearances
Your stove must be installed on a solid, level non-combustible hearth and with a gap
of at least 600mm from any combustible material such as beams or skirting. The
hearth protrusion in front of the stove to carpets or wooden floors must be at least
300mm. As it is possible, that on opening the door of the stove for fuel to fall out, a
fender must be fitted if the hearth is flush with the carpet. These are just a few
hearth specifications. Please refer to Building Regulations Approved Document J
(Hearths) for more specific details.
Minimum hearth thickness 12mm
Constructional hearth required of 125mm minimum
The appliance should be sited in a properly constructed brick fireplace or recess
allowing a gap of 100mm all round, at the rear and both sides. The fireplace walls
must be made of solid non combustible material and at least 75mm thick. The hearth
should be level and the appliance fitted at right angles to it. Fireplace walls need to
be at least 1.2m above the hearth and at least 300mm above the appliance. The
hearth has to be able to support the weight of the appliance and any flue bearing
down upon it. The clearance distances to combustible material beneath, surrounding
or upon the hearth and walls adjacent to the hearth should comply with the guidance
on the separation of combustible material given in Building Regulations Approved
Document J and also in these stove instructions.
Stove
Clearances
A B C Above
Non-Combustible 100mm 100mm 300mm 200mm
Combustible 200mm 400mm 300mm 600mm