LONGONI VITRA, User Manual

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2 . D E S C R I P T I O N A N D F U N C T I O N I N G
2.1 DESCRIPTION
The display cases are fitted with air - condensed refrigerator units composed of the following parts (as regards the
electrical system):

Condenser unit (outside of the cell)

Evaporator unit (inside of the cell)

Control and command panel located at the top part of the door (see attachment 13.2.3).

Automatic defrost

Condensation achieved by air-flow
2.2 FUNCTIONING
The refrigerated display case is fitted with an airtight refrigerator compressor, fed by a single-phase power line.
The refrigerant liquid used is type R404A.
Refrigeration cycle working principle
A sequence of thermodynamic processes causing a change in the status of a given substance (for example, liquid
refrigerant) is known as the refrigeration cycle. When the refrigerant enters the evaporator, it is transformed into
a gas (evaporation) by means of an endothermic process where heat is required and absorbed – when needed -
from the air with which the evaporator is in contact. As a result, when the refrigerant exits the evaporator, the
vapours are absorbed by a compressor and sent to the condenser. If the latter, along with the heat that the
gaseous refrigerant accumulates during the evaporation process (evaporation enthalpy) also absorbs the calorific
equivalent released during the compression process, the refrigerant returns to a liquid state. Given that
liquefaction is an endothermic process, heat is produced and then dissipated by air–flow. After exiting the
condenser, the liquid refrigerant flows through an expansion element and then returns to the evaporator, thus
completing the refrigeration cycle.
3. P R E A R R A N G E M E N T S
3.1 LIGHTING
The refrigerator must be located in a well-lit area, according to the regulations currently in force in the country
where it is being installed. The lighting system must guarantee optimal visibility from all directions, with no
hazardous reflections, and also enable clear visibility and readability of the control panel icons.
3.2 VIBRATIONS
If the apparatus is operated in accordance with the instructions, vibrations are unlikely to cause the rising of
hazardous situations.
3.3 NOISE EMISSIONS
The refrigeration unit is designed and manufactured in such a way as to reduce noise at source (see attachment
13.2.2).