Page 468 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

The City & Guilds Textbook: Plumbing Book 1

Solid fuel cookers (Aga type)
Open-flued solid fuel cookers have been around for many years. The concept
of the solid fuel cooker is very simple: a controllable fire, burning continuously,
inside a well-insulated cast iron shell, which retains the heat. When cooking is
required, the heat is transferred to the ovens. The hot plates, because they are
always hot, are covered with insulated cast iron covers, which lift up when
hot-plate cooking is required. Many models provide hot water and central
heating as well as radiated heat in the room where they are fitted.
Solid fuel cookers burn a wide variety of solid fuels, including wood, and all have
easy to empty ash pans so that the fire never goes out.

Independent boilers (freestanding)
Domestic open-flued independent solid fuel boilers are designed to provide both
p Figure 7.26 An Aga-type solid
fuel cooker domestic hot water and central heating in a whole range of domestic premises,
from the very large to the very small.
There are two main types of independent boiler for domestic use. These are as
follows.

HEALTH AND SAFETY 1 Gravity feed boilers: often called hopper-fed boilers, these appliances
incorporate a large hopper, positioned above the firebox, which can hold two
The main danger with or three days’ supply of small-sized anthracite. The fuel is fed automatically
gravity feed boilers is the
risk of fire in the hopper. to the fire bed as required and an in-built, thermostatically controlled fan
The fuel fed to the fire aids combustion. This provides a rapid response to an increase in demand.
bed needs to be regulated They are available in a wide range of sizes and outputs.
with care. 2 Batch feed boilers: these are ‘hand fired’ appliances requiring manual
stoking. They require much more refuelling than hopper-fed boilers. They
can, however, be less expensive to run in some cases and will often operate
without the need for an electrical supply, thereby providing hot water and
central heating during power failure.

Flue

Heating flow
Fuel hopper

Water jacket Combustion fan

Air
Heating return
Ash door
Ash

p Figure 7.27 Gravity-fed boiler

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