AC Not Cooling? Here are the Most Common Causes

Find out why your AC is blowing room-temperature air, the main culprits behind this breakdown, and what to do about it.

The Fan is Spinning, But the Air is Warm

It is one of the most frustrating situations of the summer: you turn on your air conditioner, hear the beep, the indoor unit starts, you feel the airflow... but 10 minutes later you realize the air coming out is at room temperature. The unit is running, but it's not cooling. Before you panic thinking you have to buy a new machine, let's review the 4 main suspects of this very common breakdown on the Costa del Sol and what you can do about it.

1. Blocked Filters and Dirty Outdoor Unit

Air conditioning works by absorbing heat from the inside and expelling it to the outside. If the indoor unit's filters are completely clogged with dust, the room air cannot reach the cold coil. Even worse, if the outdoor unit (the compressor) is covered in leaves, mud, or dirt, it won't be able to release the heat outside. The system will overheat, and the safety mechanism will shut off the compressor to prevent it from burning out, leaving only the indoor fan running. Good preventative maintenance solves this problem at its root.

2. Start Capacitor Failure

The capacitor is a cylindrical part in the outdoor unit that acts like a giant battery, giving the compressor the jolt of energy it needs to start. Due to high temperatures and power fluctuations, capacitors often swell or burn out. If you hear a loud buzzing sound ("bzzzz") coming from the outdoor unit but the fan isn't spinning, the capacitor is broken. It is a relatively quick and inexpensive air conditioning repair in Estepona, but it must be done by a qualified technician due to the extremely high risk of electric shock.

3. Refrigerant Gas Leak

There is a widespread myth that air conditioners "consume" gas over time and need to be topped up every so often. This is completely false. Refrigerant gas travels through a closed copper circuit. If your unit is low on gas, it is solely and exclusively because there is a leak (a pinhole in the pipe, a loose nut, or corrosion from sea salt). Regassing without searching for, finding, and brazing the leak is throwing money in the trash, as the gas will escape again in a matter of weeks or days, and it also harms the environment.

4. Faulty Thermostat or Electronic Board

Sometimes the problem is the "brain" of the machine. If the thermostat is broken or uncalibrated, it won't tell the compressor to turn on because it thinks the room is already cold. In other cases, small insects (like geckos or ants) can crawl into the outdoor unit and cause a short circuit on the electronic board (PCB), preventing the compressor from receiving the signal to start. A burnt-out electronic board will require the replacement of the entire part.

5. Electrical Supply Issues

Sometimes, the solution is simpler than it seems. If the circuit breaker for the AC has tripped on your main electrical panel, the outdoor unit will not receive power, even if the indoor unit remains on (in some models). Check your electrical panel before calling for service. However, if the breaker trips repeatedly every time you turn on the AC, there is a serious short circuit and you must leave it off until a professional inspects it.