No Frost

Refrigerator defrosting

Most of the modern refrigerators are equipped with automatiс defrosting systems:  No Frost system for freezing compartment; drip or No Frost system for refrigeration compartment.  Shivaki is keeping up with the times and is using automatic  defrosting systems in it's refrigerator models. Let's try to gain insight into the operation principles of modern refrigerators and find out the advantages and drawbacks of each type of defrosting systems. Compressor stops in certain intervals, ice-pieces begin to melt  and the drops go down  through draining hole into a special tray located on compressor, with further evaporation.   This process is conducted gradually and  unnoticable for users.  Since flowing water drops remind tears, such refrigerators also got the name of "crying" refrigerators. Wet walls in such refrigerators mean the normal operation of their defrosting system, but not  poor performance of the refrigerator.

No Frost or "Frost Free" system performs the defrosting of only freezing compartment or both, freezing and refrigeration compartments, dependent on the model.  Evaporator is removed from refrigeration compartment and is hidden in the cabinet behind the back wall of the refrigirator or above the freezing compartment.  Besides, the refrigerator is equipped with one or several fans ensuring the continious circulation of cold air inside the compartments.   The fan blows the evaporator, the air is cooled down and blows the compartment through designated air channels. The moisture that occurs during fridge operation will not freeze on the walls in the form of ice coating, but  «sets down» on the coldest area, i.e. evaporator. Compressor will switch off periodically, and it's ice coating will be defrosted by means of small heater, and then the moisture will be evaporated again. Any type of automatic defrosting system will surely save the time of the users. 

Of course, defrosting can not be avoided completely: doesn't matter how modern your refrigerator is, it's recommended to clean it's internal surfaces with power off at least 1-2 times per year. There is a great polemics among experts and users regarding merits and demerits of Nо Frost system.

Merits of No Frost system:

  • More uniform distribution of cold air, and hence temperature across the refrigeration (freezing) compartment.  
  • Quicker temperature recovery in compartment after loading the big amount of food products or after several door openings (it improves the products' chilling and preservation quality, and saves energy).

Demerits of No Frost system:

  • Low humidity level in  compartment due to continuous force air circulation resulting in fast «drying» of food products. 
  • The conditions for fast drying are certainly present but only if the users do not observe the product package rules.

Lower volume of chilling compartment due to additional equipment. Higher noise level during operation. Additional noise come from fans, but some models with "No Frost" system are equipped with low-noise fans, and therefore they are even more quiet than their drip-type "counterparts". Higher power consumption when using the refrigerator. Higher price due to complex refrigerator design and additional equipment (eg., fans). But this difference is not significant. In general, merits and demerits of "No Frost" system practically compensate each other. Shivaki refrigerator models combine both systems for automatiс defrosting: for refrigeration compartment – drip-type system, for freezing compartment – No frost system. This allows to combine the advantages of both systems and to improve the refrigerator performance.