Inverter Vs Non-Inverter Air Conditioners: Pros, Cons, And Differences Explained
Air conditioners come in various shapes and sizes, ranging from complicated HVAC systems to portable AC units. No matter the type of AC you're considering, they are all further bifurcated into inverter and non-inverter varieties. The former is almost always more expensive, but makes up for it with improved efficiency. Inverter ACs have existed since the 1980s, but their market adoption increased markedly only in the last decade thanks to tightening energy efficiency standards across the globe.
Understanding how inverter air conditioners work compared to their plain vanilla counterparts is key to figuring out why they are cheaper to run, and the underlying pros and cons of choosing one over the other. It all boils down to the AC compressor, which circulates the refrigerant between the indoor evaporator and outdoor condenser units and achieves rapid cooling by forcing the refrigerant to change phase from liquid to gas and vice versa.
The compressor in a non-inverter AC operates at a fixed speed, which forces it to run at maximum power until the desired temperature is attained. The compressor is then switched off until the room warms up, at which point it spools up to full power. This cycle continues for as long as the unit is on. Inverter ACs, on the other hand, can vary compressor speed and power. Once the temperature setpoint is reached, an onboard microcontroller significantly reduces the compressor power and runs it at lower speeds to maintain a steady temperature.
Inverter ACs are better in every metric, except upfront costs
The benefits of choosing an inverter air conditioning system don't end at energy savings. Because regular ACs can't vary their compressor speeds, they must wait for the room to get warm before kicking back in at full power to cool it down. This leads to noticeable temperature fluctuations compared to the tight temperature control of their inverter counterparts.
Inverter ACs are significantly quieter as well, especially since they ramp down to a lower compressor speed once the desired room temperature is achieved. Meanwhile, non-inverter air conditioners make quite a racket when the compressor switches on at full power. This can get quite annoying as the process repeats endlessly. The noise levels are relatively manageable when you're dealing with large HVAC systems and split air conditioners, which usually have the compressor placed a fair distance away from the occupants of the room being cooled. However, the reduced noise levels of inverter ACs are especially important for portable and window AC systems, bearing monolithic compressor and evaporator units.
The compressor is the hardest-working part of any air conditioning system, and inverter ACs' ability to run the compressor at lower speeds and power levels will reduce wear and tear. While the average lifespan of an AC unit is about a decade, if we compare units of similar build and material quality, the compressor on an inverter AC is likely to last longer than a non-inverter unit. On the flip side, inverter ACs also require advanced microcontroller-equipped electronics that are significantly more expensive to repair compared to the simpler and cheaper electronics of regular ACs.
Should you by an inverter or non-inverter AC?
Inverter ACs are quieter, more comfortable, cheaper to run, and will last longer. Their increasing popularity has also reduced the price gap between inverter and non-inverter AC units. But if your budget's tight, the lower upfront cost of non-inverter ACs makes sense in some scenarios, especially if you don't plan on using the unit for many years. The energy efficiency of inverter ACs primarily comes into play when you use them for long stretches exceeding eight hours a day or pay high unit rates for electricity.
Therefore, a non-inverter AC is a viable option if you don't plan on settling down in the same house for many years, or otherwise don't use air conditioning for extended periods. There are even times when choosing an inverter AC might even be at odds with energy efficiency, such as when an inverter AC would be too large for a room, exceeding the 115% rule for air conditioners. In such cases, buying a correctly sized non-inverter AC is the smarter choice.
On the flip side, you are better off choosing the quieter inverter variants if you are in the market for window or portable AC systems, since these have compressors operating in proximity to the user. If the higher initial investment isn't a hindrance in the pursuit of better temperature regulation and lower noise, an inverter AC is the right choice for you.