Why shouldn’t you set the air conditioner to 26°C at night?

Why You Shouldn’t Set Your AC to 26°C at Night

When summer heat feels relentless, many people instinctively lower their air conditioner to cool down fast. While setting it to 26°C might seem like a good balance between comfort and energy use, experts warn that this temperature—especially at night—can cause health issues, waste electricity, and put unnecessary strain on your system.

The best AC setting depends on the day’s peak outdoor temperature. For example, if it’s 34°C outside, setting your unit to around 26–27°C during the day keeps a safe 7–8°C difference from the outdoors. This gap helps prevent respiratory irritation, avoids sudden body temperature changes, and keeps energy consumption in check.

During the day, 26°C is generally comfortable. But at night, your body’s temperature naturally drops as you enter deep sleep. Your metabolism slows, your muscles relax, and your core heat decreases. In this state, what felt comfortable earlier can start to feel chilly in the early morning hours. Prolonged exposure to cooler air at this stage can disrupt sleep, cause muscle stiffness, or increase your chances of catching a cold.

For restful and healthier sleep, technicians recommend setting your AC to around 28°C at night. This temperature is warm enough to prevent overnight chills while still providing comfort. It also cuts down on power usage, which can noticeably lower your electricity bill over time.

If 28°C feels too warm, a good alternative is to use Sleep Mode while keeping the starting temperature at 26°C. This feature automatically increases the set temperature by 1°C after the first hour and another degree after the second hour, gradually reaching 28°C by early morning. This prevents sudden temperature shocks to your body while maintaining steady comfort.

Some people complain that 26°C doesn’t cool their room enough. Often, the problem is that the AC unit is too small for the space, making it struggle to cool even at lower settings. In such cases, no temperature adjustment will fully fix the issue—you’ll need to ensure your AC capacity matches your room size.

Other factors can also cause poor cooling, including dirty air filters, blocked vents, low refrigerant levels, or compressor malfunctions. Simple maintenance, like cleaning filters and ensuring air vents are unobstructed, can greatly improve efficiency. But if problems persist, a certified technician should check for refrigerant leaks or mechanical faults.

The takeaway? Setting your AC to 26°C all night may not be the healthiest or most efficient choice. For better sleep, reduced energy use, and less wear on your system, aim for 28°C at night or use Sleep Mode for a gradual temperature rise. Your body—and your electricity bill—will thank you.