Why your AC’s cool mode fails in the monsoon? Here’s one button that fixes it

Monsoon weather often brings a different kind of indoor discomfort that standard summer cooling does not fully address. Even when outdoor temperatures fall, the air can remain heavy with moisture, leaving rooms feeling sticky and clammy despite prolonged air conditioner use.

Many people respond by sharply lowering the temperature and running the air conditioner in cool mode. However, dry mode, a feature available in most units, is designed for high-humidity conditions and can make indoor spaces feel more comfortable while also reducing electricity use during the rainy season.

Cool mode and dry mode

The difference lies in how the two modes treat the air. In cool mode, the system focuses on lowering the room temperature as quickly as possible. To do this, the compressor runs continuously and pushes a large volume of chilled air into the room. During the monsoon, though, high humidity prevents sweat from evaporating properly from the skin. As a result, the room may become cooler without losing its sticky feel.

Dry mode works differently. Instead of prioritising temperature reduction, it focuses on removing moisture from the air. The internal fan runs at a much lower speed, and the compressor switches on and off intermittently rather than running constantly. As humid air passes slowly over the cooling coils, water vapour condenses into liquid and drains out of the unit.

Once this moisture is removed, the room’s relative humidity drops. That allows natural evaporative cooling to work more effectively on the skin, making the same room temperature feel cooler and more comfortable than it would in humid conditions.

Why dry mode uses less power

This also affects electricity consumption because the compressor is the most energy-intensive part of an air conditioner. In cool mode, it keeps running continuously to force temperatures down without addressing the moisture load. In dry mode, by contrast, the compressor cycles intermittently, which uses less power overall.

For households that run their air conditioner for several hours a day during the monsoon, shifting from constant cooling to periodic dehumidification can lead to a noticeable reduction in electricity use. The energy saving comes from reducing the mechanical load needed to bring down the temperature and instead focusing on removing excess moisture from the air.

Thermostat setting matters

One common mistake is switching to dry mode while keeping the thermostat at a very low temperature, such as 18°C, in the belief that it will speed up the process. In practice, such a setting forces the compressor to keep running in an effort to meet the target, overriding dry mode’s normal cycling pattern and removing much of its energy-saving benefit.

Experts recommend setting the thermostat between 24°C and 26°C when using dry mode. In that range, the cooling coils remain cold enough to condense and remove water vapour without overworking the compressor. After the humidity drops, 24°C can feel comfortable, even though the same temperature may feel oppressive on a humid day.

How to maintain efficiency

A few simple steps can help maintain the efficiency of dry mode. Doors and windows should be kept shut so that outside moisture does not keep entering the room and raising humidity levels again. Air filters should also be cleaned regularly, as monsoon conditions can encourage the build-up of mould, fungus and dust. A clogged filter restricts airflow and reduces the coils’ ability to remove moisture.

Running a ceiling fan at low speed alongside the air conditioner can also help circulate dehumidified air evenly across the room. Because dry mode does not push out a strong stream of cold air in the way cool mode does, a low-speed fan can improve air circulation without creating a strong or uncomfortable draft.

During the monsoon, dry mode can offer a more effective way to deal with indoor discomfort by removing excess moisture rather than only lowering the temperature. Used with a moderate thermostat setting and basic maintenance, it can improve comfort and reduce power consumption at the same time.