DE3010345

In refrigerators having two compartments 2,3 (Fig. 1) for respectively preserving fresh and frozen foods, the frozen food compartment normally held at about -18 DEG C cannot be used to freeze foods because regulations require a considerably lower temperature (e.g. -30 DEG C) that will freeze foods within 24 hours. The temperature control arrangement includes a two-way switch 26 (Fig. 3) which can be set by the user to cause the frozen food compartment to reach such a low temperature that foods can be frozen within a prescribed or determined period. A temperature sensor 14 e.g. an NTC Thermistor is located in the coldest part of the fresh food compartment and is connected in an arm of a bridge circuit means for comparing the compartment temperature with a first or a second reference temperature value set up on pot 25 and R50 and selectable by switch 16. Means e.g. a triac 33 Fig. 3 controls the operation of the refrigeration circuit compressor 6 in dependence upon the result of the comparison. Selection of the first reference temperature signal causes the temperature in compartment 2 to be held at, for example 4 DEG C and hence the temperature in compartment 3 to be held at, for example, -18 DEG C. Selection of the second reference temperature signal causes the temperatures in the compartments 2 and 3 to be held at, for example, 1.5 DEG C and -30 DEG C respectively. A thermistor 15 responsive to evaporator temperature, is connected in a second bridge circuit coupled to amplifier C. This functions to activate the compressor 6 when a given temperature is detected indicating that defrosting by a heater M is completed. The defroster heater may be timer controlled.