Refrigerator
A thermally insulated appliance that cools food below ambient temperature.
A refrigerator, commonly shortened to fridge, is a commercial and home appliance consisting of a thermally insulated compartment and a heat pump that transfers heat from its inside to its external environment so that its inside is cooled to a temperature below the ambient temperature of the room. Refrigeration is an essential food storage technique around the world, as the low temperature reduces the reproduction rate of bacteria, lowering the rate of spoilage. The refrigerator replaced the icebox, which had been a common household appliance for almost a century and a half.
- home freezers as separate compartments i
- 1940
- optimal temperature range for perishable
- 3 to 5 °C (37 to 41 °F)
- FDA recommended refrigerator temperature
- at or below 4 °C (40 °F)
Lore & Background
Artificial refrigeration began in the mid-1750s and developed in the early 1800s. The introduction of Freon in the 1920s expanded the refrigerator market during the 1930s. Home freezers as separate compartments were introduced in 1940, and frozen foods, previously a luxury item, became commonplace.
Reader's Guide
The refrigerator is a cornerstone of modern food preservation, allowing households to keep food fresh for longer and enabling bulk purchases of perishable items. Its development from early ice-based cooling to artificial refrigeration systems—including vapor-compression and absorption cycles—transformed food storage globally. Commercial refrigerator and freezer units were in use for almost 40 years prior to common home models. The freezer-over-refrigerator style became basic from the 1940s until side-by-side models broke the trend. Newer refrigerators may include automatic defrosting, chilled water, and ice dispensers. The refrigerator typically consumes up to 50% of the energy used by a supermarket, and glass doors improve efficiency over open display cases. The introduction of non-toxic synthetic refrigerants like Freon expanded home use, though later bans addressed ozone layer damage.
Did You Know?
- Home freezers as separate compartments were introduced in 1940.
- The FDA recommends refrigerators be kept at or below 4 °C (40 °F).
- Commercial refrigerator units were in use for almost 40 years before common home models.
Frequently Asked Questions
What is a refrigerator?
A refrigerator is a thermally insulated appliance that uses a heat pump to pull heat out of its interior and release it into the surrounding room, keeping the inside cooler than the ambient temperature. It serves as a primary method for preserving food by slowing bacterial growth.
How does a refrigerator actually cool its contents?
Rather than generating cold directly, the unit's heat pump extracts thermal energy from the insulated compartment and dumps it into the external environment. This continuous outward transfer of heat is what maintains the lower internal temperature.
What is the ideal temperature setting for a refrigerator?
For perishable foods, the recommended internal range sits between 3 and 5 degrees Celsius (roughly 37 to 41 degrees Fahrenheit). Staying within this window keeps bacterial reproduction rates low enough to noticeably delay spoilage.
What appliance did the refrigerator replace?
Before the fridge became widespread, households relied on the icebox, which had been a standard appliance for roughly a century and a half. The vapor-compression refrigerator made that manual ice-replacement cycle obsolete.
More in Energy & Power 1-24
Spotted an error? Know more?
This is a living reference — every entry is fact-audited, and reader corrections feed straight into our audit queue. Suggest an edit · See this site's audit record