Each day, we take cold drinks, unspoiled food, and frozen treats for granted, but in the days before proper electric refrigerators, keeping things cool was a major challenge. Salting and keeping food underground, or otherwise paying a bundle for shipped ice, meant that the refrigeration process was also quite laborious — and often so expensive that only the very wealthy could afford it. Anyone old enough to remember the sound of horse-drawn carriages delivering ice in the early hours of morning? We didn’t think so …
So in today’s world of long-lasting food, reduced illnesses, and general convenience, it’s nice to have a basic working sense of how refrigeration works, and how your modern fridge is keeping your food at the perfect temperature. First, you’ve got to have an understanding of the Second Law of Thermodynamics, which describes how substances of different temperatures interact when they collide: the cooler substance will heat up, and the warmer substance will cool down. You’ll notice this process when you hop out of a pool and feel cold, even in bright sunlight. When the sun hits the water on your skin, it begins to evaporate, which takes some of your body heat along with it, making you shiver.
Refrigerators today contain a gas called HFC, which (like all gasses) will get warmer as it’s pressurized — and your fridge’s compressor will do just that. This compressor pushes the gas through your fridge’s outside coils, where it begins to cool down as it interacts with your room temperature. It transforms into a liquid once it reaches about -27 degrees Celsius. Once the liquid begins to pass through a tiny hole called the expansion valve (or device) and back into the interior coils of the fridge, it cools down even more. The colder substance in the interior coils thus cools down the interior of the fridge (according to the Second Law of Thermodynamics), absorbing the heat. Through this interaction, the HFC evaporates and becomes a cold gas, which is drawn in by the compressor to begin the process all over again.
When you hear your refrigerator turn on, it means the thermocouple has sensed that some cold air has escaped and the internal temperature is rising. This device triggers your compressor and re-starts the chemical cycle.
With so much fascinating physics and chemistry at work, there are (understandably!) a number of instances where something could go wrong. Your appliance can leak too much cold air with an unsealed or damaged door; your compressor or motor can malfunction; the pipes may become damaged; and there can of course be electrical issues. That’s why it’s wise to have our appliance experts on speed-dial to help you sort out any issues with repairs. We’re serious about the cooling process — it’s why “refrigeration” is part of our name, after all! And it’s been our pleasure to serve the GTA’s refrigeration needs for over fourteen years.
The next time you sense something amiss with your fridge, give us a call and we’ll help you dial back the temperature to a comfortably frosty level — no horse and carriage necessary.