Technology
Inverter or fixed-speed air conditioner: the difference, simply
A conventional unit has two states – full power on, and off. An inverter controls compressor speed smoothly, like the accelerator in a car. That difference decides the electricity bill, the comfort and the noise.
3 min readUpdated
How the inverter works
The electronics convert the supply and feed the compressor exactly the power needed to hold the set temperature. Once reached, the unit does not stop – it drops to minimum speed. The result is a temperature within a degree and no cold–warm cycling.
How much electricity it saves
In daily use an inverter unit uses noticeably less than a conventional one of the same capacity, because it avoids energy-hungry starts and runs mostly at partial load, where it is most efficient. The seasonal SEER and SCOP of inverter models are markedly higher, which shows directly in the energy class.
Heating and low temperatures
The inverter is also the only sensible choice for heating: a conventional unit loses output quickly below zero and defrosts often, while an inverter holds heating output down to −15°C and lower.
When a fixed-speed unit still makes sense
Only for very rare use – a few days a year – on a tight budget, where the lower purchase price cannot be eaten by bills. For everything else the inverter pays back within a season or two.
Frequently asked questions
Is a conventional unit noisier?
Yes – it always runs at full speed and starts abruptly. An inverter spends most of its time at low speed, where it is quietest.
Is an inverter more expensive to repair?
The electronic module is more complex, but modern inverter units are reliable and the leading brands cover the compressor for a long period. With a proper installation faults are rare.
Are all units in the catalog inverters?
The wall-mounted units we offer are inverters. You can filter by "inverter" in the shop.
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