Specifications

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6720649497 SM HP270-1 2012/09 en
Efficiency Definition
The basic compressor-driven refrigeration cycle consists of one compressor, two heat exchangers (evaporator and
condenser) and a throttling device (expansion valve). These components form the circuit in which the refrigerant
circulates and the cycle operates between the two pressure levels P1 and P2, and the temperatures T1 and T2,
where T1 > T2.
Pict.64 – Diagram of enthalpy and pressure relation
Superheat
The superheat is the difference between the evaporating temperature and the temperature of the gas coming from
the evaporator. The evaporating temperature is determined with a pressure gauge and the temperature of the gas
is measured with a digital thermometer
 Takes place in the evaporator and indicates the gas temperature raise (superheat) after it has changed the
into gas state
Attention: The more refrigerant the expansions valve lets flow into the evaporator, the lower the superheat will be
achieved. Since there is more liquid refrigerant in the evaporator there will be less gas and the gas will then be less
superheated.
Pict.645– Expansion valve representation
 The superheat describes how efficient is the evaporator for the vaporization
Evaporator
Condenser
Pressure
p
art