Whether in the middle of summer or during an unexpected heatwave, air conditioning has become a great ally for Brazilians. But to ensure that it really works as expected, it's essential to choose the right model, taking into account your needs and the room where it will be installed.

How do you decide which air conditioner to buy?

It's not always easy to decide between the various types available on the market. From traditional window models to modern split systems, each offers specific advantages.

To make the best choice, it's important to consider:

Size of the room where it will be installed

The capacity of the air conditioner should be proportional to the size of the space where it will be installed. Larger rooms require units with greater power, measured in BTUs (British Thermal Units).  

A basic calculation that can help is to multiply the area of the room by 600 BTUs for residential spaces or 800 BTUs for commercial environments, taking into account factors such as the number of people and the incidence of sunlight.

Some websites already have calculators that do this, but you can also use the image below:

Area	Morning sun	Sun in the afternoon or all day
9 m²	7.000 BTUs	7.500 BTUs
12 m²	7.500 BTUs	9.000 BTUs
15 m²	9.000 BTUs	12.000 BTUs
20 m²	12.000 BTUs	18.000 BTUs
25 m²	18.000 BTUs	22.000 BTUs
30 m²	23.000 BTUs	24.000 BTUs
40 m²	24.000 BTUs	30.000 BTUs
50 m²	31.000 BTUs	36.000 BTUs
60 m²	36.000 BTUs	48.000 BTUs
70 m²	42.000 BTUs	58.000 BTUs

 

Types of air-conditioning

With the advance of technology, air conditioners have evolved significantly, gaining a variety of models that meet the different needs and preferences of consumers.

Below are the main types and their advantages:

Window air conditioning

Traditional and popular in the country, window air-conditioning does its job well in small and medium-sized environments. It is ideal for those looking for a practical and affordable solution, both in terms of initial cost and maintenance.

Ar-split air-conditioning

 

Considered one of the quietest, this model is gaining more and more space in Brazilian homes and commercial premises. The condenser and evaporator are separated and installed at different points in the building.

Portable air-conditioning

Portable units are easier to install, but they can only cool small rooms. If it is used in larger rooms, it will not be enough.

Energy consumption

Another important factor when choosing an air conditioner is energy consumption. Models with greater energy efficiency, indicated by the Procel label, help save on electricity bills and reduce environmental impact.

Inverter units stand out in this respect, as they adjust the speed of the compressor according to the needs of the room, avoiding energy peaks that turn the compressor on and off repeatedly.

This technology is especially advantageous in periods such as summer, when air conditioning is used more frequently. Although they may have a higher initial cost, the savings made over time, both in summer and in other seasons, make the investment worthwhile.

In the colder months, when air conditioning use may be less constant, inverter models continue to be efficient, maintaining the ideal temperature with lower energy consumption. In this way, investing in a high-efficiency appliance is advantageous all year round.

How to calculate the energy consumption of air conditioning?

Understanding how to calculate the energy consumption of your air conditioner helps you to predict monthly costs and ensure that the appliance you choose is really efficient and suitable for your budget.

The energy consumption of an air conditioner is measured in kilowatt hours (kWh), which is the amount of energy used by the appliance during one hour of operation.

Step-by-step calculation of air conditioning energy consumption:

1. Check the power of the appliance (in watts)
   The power is usually indicated on the product label or in the user manual. If the value is given in BTUs, you can convert it to watts by dividing the number of BTUs by 3.412. For example, a 7,000 BTU air conditioner consumes around 2,051 watts.
2. Calculate daily consumption
   Multiply the power (in kW) by the number of hours the air conditioner is on per day. For example, if the 2,051 watt (or 2.051 kW) unit is used for 8 hours a day, the daily consumption will be approximately 16.4 kWh.
3. Calculate monthly consumption
   Multiply the daily consumption by the number of days in the month you expect to use the air conditioner. Using the previous example, for 30 days of use, the monthly consumption would be around 492 kWh
4. Estimate the monthly cost
   To find out how much this consumption represents in terms of cost, multiply the monthly consumption by the kWh charged by your energy supplier. If the cost per kWh is R$0.60, the monthly cost would be approximately R$295.20.

Tips for reducing air conditioning energy consumption

Even after you've bought an air conditioner, there are a few practical tips that can help you reduce your energy costs and, consequently, your electricity bill at the end of the month:

• Keep the filters clean;
• Set the temperature properly;
• When switching on the appliance, keep windows and doors closed;
• Appliances installed outdoors must be protected from the sun's rays and care must be taken not to block ventilation;
• Switch off the appliance when the room is unoccupied.

Safety tips when using air conditioning

 

 Use the air conditioner in a socket exclusively for the equipment (never connect other appliances to the same socket);

 

Don't use "T" plugs for equipment that is constantly plugged into the socket. This prevents overheating and short circuits, which can damage your home's electrical installation;

 

If you notice that part of the equipment's wire is bare or inadequately insulated, call a technician. The purpose of insulating cables is to confine electrical fields, allowing for a solid grounding of cables, which makes them safer, reduces the risk of shocks, short circuits and fires.

 

Find out more:

Tips for buying household appliances: electric shower

Tips for buying household appliances: refrigerator