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SYSTEM DESCRIPTION
Ariterm bio-heating systems are designed for heating the boiler water of central heating sys-
tems. The system usually comprises a central heating boiler, fuel feed and burner, fuel stoker
and a control system with the necessary safety equipment. The Arimax step grate boiler is most
suited to the burning of high-quality wood chip.
Its operation is based on the temperature of the boiler water measured by the boiler sensor. The
burner is activated when the temperature falls below a certain limit value. Below this limit value,
the automatic control system handles the feed of fuel and combustion air so that operation is
as balanced as possible. The automatic control system thus aims to keep the boiler at a constant
temperature by increasing or reducing the power of the burner. If the heat requirement falls
below the level of the lowest thermal load, the control system switches to maintenance mode.
The heat requirement activates both feed augers, which transport the fuel to the burner. The
combustion air fans introduce combustion air into the combustion process. There are separate
fans for primary, secondary and tertiary air.
Once the feed augers have emptied the intermediate tanks, the stoker auger is activated by
means of an optical level guard in an intermediate tank. The stoker auger refills the intermediate
tanks and stops. If the stoker auger runs for a pre-set filling time without fuel arriving at the
intermediate tank, a conveyor also starts up. The conveyor pushers transport additional fuel to
the stoker auger.
In the burner, the heat energy in the fuel is released as heat. Hot flue gases are cooled on their
way out of the boiler and the heat is transferred to the boiler water. The soot and ash emissions
of the boiler are reduced by means of a flue gas cleaner. The boiler operates on negative pressu-
re and so is equipped with a vacuum-controlled flue gas extractor. This extractor maintains a
balanced negative pressure in the firebox and ensures an even combustion process.
Note that the numbers of fuel augers, ash augers, combustion air fans and other fittings may
vary depending on the size of boiler and level of equipment selected.
