Compressor Protection Against High Condensing Temperature; Advanced Fan Control - Danfoss EET Series User Manual

Refrigeration controller, type EET series
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Compressor protection against high condensing temperature

If the condenser is blocked due to dirt / dust and the condenser is unable to cool down the refrigerant properly due
to lack of proper heat exchange, it will affect its performance and greatly reduces system life. This feature will
protect the system and compressor via a two-step protection mechanism. The controller can be configured to set an
early warning temperature by the user, when the compressor can keep running, and then a second level of
condenser temperature beyond which the compressor is switched off until the temperature comes down to an
acceptable limit. This would help to improve the compressor life by running within the allowed operating envelope
of the compressor.
Figure 4: Compressor protection against high condensing temperature
Block Limit (cBL)
Cond alarm (cAL)
OK Limit (coL)
Compressor
Cond alarm

Advanced Fan control

Advanced Fan control helps maintain a uniform cooling by switching fan ON and OFF during the compressor OFF
cycle. This feature reduces the overall energy consumption while maintaining a uniform temperature in the cabinet.
© Danfoss | Climate Solutions | 2023.07
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