Inverter AC and inverter fridge: what the word actually means

Short answer: An inverter AC or fridge varies its compressor speed instead of switching it fully on and off. It uses less electricity and is quieter when it runs for many hours, but costs more to buy.

In shops, "inverter" means two completely different things. A home inverter is the battery backup for power cuts. An inverter AC or fridge is about how the compressor inside is driven. They are unrelated.

How a regular compressor works

A non-inverter air conditioner runs its compressor at full speed until the room is cool, then switches it off. When the room warms up, it switches on again at full speed. That stop-start cycle wastes energy and makes the room temperature swing.

How an inverter compressor works

An inverter model changes the compressor's speed. It cools hard at first, then slows down and keeps running gently to hold the temperature. The result:

• Lower electricity use when it runs for long periods
• Steadier temperature, without the hot and cold swings
• Quieter operation, because it rarely starts from zero

Good to know: The savings come from long running hours. If you only switch an AC on for an hour or two on the hottest days, a cheaper non-inverter model may cost less overall.

Is it worth paying more?

Compare the energy rating label of the exact models, not just the word inverter. Then think about hours of use: an AC that runs every night through summer, or a fridge that runs all year, will usually repay the higher price over time.

Inverter appliances use electronics that are more sensitive to voltage swings. Where the supply fluctuates, use a suitable stabiliser or check that the model has a wide operating voltage range.

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