Specifications

Hercules Boiler Model 8
Connection to Chimney Flue
A single wall metal fluepipe is suitable for connecting the stove to the chimney but is
not suitable for using for the complete chimney. It is important that the connection
between the stove spigot and the flue pipe is effectively sealed with heat resistant
fire cement and/ or glass fibre rope to prevent harmful gases leaking into the room.
The diameter of the flue spigot (pre fibre roped) provided with the stove is 8”
(200mm) and can only be fitted to the top of the stove and must be tightly fitted to
the opening. Air must not be drawn in at this point as it will affect the stoves
performance. The stove may be fitted with a 7” (175 mm) flue (In most situations
175mm diameter flue pipe will not be suitable for chimneys less than 7.5m high, and
must be used in conjunction the ‘reducer ring’ supplied with the stove as a standard
part).
To get the best transfer of heat from the stove into the room there are two factors to
consider when installing into a fireplace recess.
Firstly, the flue pipe from the stove must pass through a top ‘register plate’. A top
register plate is the term used for a flat plate which is installed inside the chimney
(usually out of sight) to prevent heat in the room being drawn up the chimney to
waste when using the top or rear flue outlet. This register plate must be made of a
non-combustible material such as steel, asbestolux, or masterboard. It is advisable to
seal this register plate to the walls of the chimney and also around the flue pipe.
Provision of a trap door in this closure plate, or a soot door in the flue for access to
clean the chimney from time to time, is recommended.
Secondly, the more forward the stove can be sited on the hearth, the more heat will
be radiated into the room. But remember the 600mm clearance distance from
combustible materials and the 300mm distance to the front of the hearth.
Combustion Air Supply
In order for the stove to perform efficiently and safely there should be an adequate
air supply into the room in which the stove is installed to provide combustion air.
This is particularly necessary in modern houses where drafts have been almost
eliminated by double glazing etc.
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. It is necessary to install a wall vent to
provide the necessary combustion air and to prevent the depletion of oxygen in the
room.
Plumbing the Appliance
The plumbing must be in accordance with all the relevant regulations and practices.
The central heating should be pump driven as with other types of boilers. 28mm
diameter flow and return piping must be used for the initial run to the tank or heat
store. The shorter the run of pipe work the more effective the water heating will be,
the cylinder and pipe work should be lagged to minimise heat loss.