Household refrigerators may operate at different surrounding temperatures and thermostat settings. Pre-condition for designing more efficient refrigerators is to have a good understanding of the impact different surrounding temperatures and thermostat settings may have on temperature distribution or conditions within components. Awareness of the values of thermal conductivity of heat exchangers and casing further contributes to this cause. To collect all the relevant data, we measured a temperature in fourteen different points across the refrigeration system, conducted reverse heat leakage test, and test during which we influenced the condenser's performance. We find that surrounding temperatures influence temperature distribution and conditions within the low pressure part of the system, while thermostat settings influence high pressure part. It is evident that compressor's efficiency is dependent upon the operating conditions, whereby higher surrounding temperatures and thermostat settings adversely affect its performance. The measurements and calculations show lower value of thermal conductivity of the evaporator in fridge in comparison to the value of thermal conductivity of the evaporator in freezer. On the contrary, the value of thermal conductivity of fridge housing is higher in comparison to the value of thermal conductivity of freezer housing.
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