Specifications

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Operation of coffee maker:
The desired quantity of water is poured into
the water chamber of the pot and the desired
amount of a fairly coarse-ground coffee is placed
in the top chamber. It is important that the water
level be below the bottom of the coffee chamber.
When the supply is given to the heating
element, the temperature rises until the water in
the bottom chamber boils. While some models may
have a one-way aromalock valve at the bottom of
the tube which forces some of the boiling water up
the tube, most operate on the simple principle that
the rising bubbles will force the liquid up the tube.
The hot water is distributed at the top over the
perforated lid of the coffee chamber. This water then
seeps through the coffee grounds and leaves the
Fig.10.8 - Percolator type coffee maker
coffee chamber through the bottom, dropping back into the lower half of the pot. The rest of the
colder water at the bottom is meanwhile also forced up the tube, causing this whole cycle to
repeat continually.
As the brew continually seeps through the grounds, the overall temperature of the liquid
approaches boiling point, at which stage the “perking” action (the characteristic spurting sound
the pot makes) stops, and the coffee is ready for drinking.
Drip Coffee maker :
This type simulates the working of a manual drip coffee brew, where a filter containing the
grounded coffee is placed over a carafe and hot water is poured over the coffee ground and
then, passing through the filter, drips as coffee into the carafe. This can be done manually or by
using an electric or automatic drip coffee maker. An average size for a drip brew coffee maker
would be a 12 cup coffee maker.
Automatic drip coffee maker:
In automatic type, Water from a cold water reservoir passes through a flexible tube into a
heating chamber where the water is heated, a thermostat prevents that it is heated too much
and converted into steam. This heated water gets moved up towards a spray head from where
it drips down onto the ground coffee. This coffee is normally contained in a, paper or gold, filter
hold by a container, which is located below the spray head. The water passes through the filter,
the coffee and than drips into a glass or thermos carafe. When brewing more as 12 cups coffee
a more powerful heating element is necessary.