Appliance Science: How Do Freezers Actually Work?
We tend to take freezers for granted as they are somewhat of a household staple along with fridges, washing machines & dishwashers. Without the ability to freeze, we would have no capacity for medium-term food storage and would have to refrigerate everything that we buy and eat it before the sell-by date. This would mean constant trips to the shops and products such as frozen veg, ice cream, oven chips and much more would simply not exist! With spring now here and summer a matter of weeks away, we have bolstered our stock list with a fresh batch of high quality graded freezers and fridge freezers.
Technically most of us are unaware as to how a freezer even achieves such low temperatures other than that we plug it in and switch it on! The real science behind how a freezer works is truly fascinating.
A Little History
Throughout the late 1800s and well into the 20th-century families used what were known as ‘cool boxes’ to keep their food fresh. They consisted of a wooden box with a zink lined interior which was partitioned into two compartments, one containing the food and the other containing a big block of ice for cooling. Other than the cool box, pickling and canning were pretty much the only ways of preserving food for longer periods of time so the concept of freshly preserving it for the long run was out of the question.
Refrigerant
Freezers use a chemical refrigerant called HFC-134a, a hydrocarbon-rich gas that is not harmful to the ozone layer or environment, unlike its predecessor Freon. HFC-134a starts out in gas form where it is then compressed using the freezers compressor unit causing it to get very hot. The HFC-134a gas is then pumped throughout a network of metal coils where it starts to condense into a liquid. This liquid is then forced through a pressurised expansion value which turns it into a mist and absorbs all ambient heat and creating a cool environment. This process is repeated indefinitely to create a cold enough temperature to sustain freezing. The scientific concept behind how evaporation removes heat energy is very similar to the cooling sensation you feel on your skin when it comes into contact with alcohol.
Metal Coils
The metal coils in a freezer are very important as they provide an environment for the HFC-134a gas to condense and cool. A common problem on many old freezers is that the metal tube ways can become blocked with grime and residue over the years. This means that the HFC-134a cannot easily lose its’ heat resulting in a higher overall freezer temperature.
The Compressor
This device performs a critical function which keeps the process of continuous refrigeration possible. After the cycle is complete the refrigerant comes back round in liquid form having condensed back from mist form. Once collected the compressor converts it back into a gaseous state ready to be pumped through the first set of coils and then back through the expansion valve.
Time For A New Freezer?
Feel like you need a new freezer? It may be that you have noticed that your current freezer is struggling to keep a good temperature or that it is just in need of an upgrade. Borshch Electric specialises in high quality graded freezers and fridge freezers in the Erdington area. We can offer savings of up to 40% on brands such as Smeg, Beko, Grundig, Montpellier and Ice King. We even offer same day delivery on selected items so call our Erdington store today on 0121 448 0202 .