The AC is working, but your home is still hot: What happens in UAE summers, health risks and fixes
Sometimes the AC is perfectly fine, it’s just fighting a battle it was never sized to win
Your AC is running. The vents are blowing cold air.
And you're still sweating.
Why?
One of the most common frustrations during summers: Temperatures regularly push past 45°C, buildings absorb heat all day, and air-conditioning systems are forced into a near-constant battle against the outdoors.
Yet, experts say the problem is not always a broken AC unit. Sometimes, the issue is hidden in the walls, windows, ductwork, or even the body itself.
According to Ranjana Chhabra, Director of Growth & Partnerships at INSTECH, many people misunderstand how air conditioners actually work. “Most people assume an air conditioner ‘creates’ cold air. In reality, it removes heat from inside a home and transfers it outside,” she explains. “In Gulf summers, that process becomes extremely demanding.”
The distinction matters. When the heat entering a home exceeds what the AC can remove, rooms continue to feel warm even if the unit is technically functioning.
The UAE climate can create a double challenge for cooling systems, explains Koshy Philip, Head of Operations at Efficient Chill. The intense inland heat in places like Al Ain and Abu Dhabi, combines with heavy coastal humidity in cities such as Dubai and Sharjah.
“Both conditions place extreme demand on air conditioning systems," he says.
In many UAE towers, cooling systems are also interconnected through district cooling or chilled water networks. Chhabra says performance depends on 'every stage of the supply chain functioning efficiently', from chillers and pumps to airflow and controls.
The issue may not always be limited to one apartment. A reduction in chiller efficiency or chilled water flow can affect multiple units across an entire section of a building.
However, before assuming there is a larger infrastructure problem, experts say residents should first understand the warning signs inside their own homes.
Most people assume an air conditioner ‘creates’ cold air. In reality, it removes heat from inside a home and transfers it outside. In Gulf summers, that process becomes extremely demanding...
When your AC is trying, but losing
Amit Seth, founder and CEO of Seth International Technical Services, says overheating despite air conditioning is usually a sign that 'something isn’t working as it should'
In the UAE, where outdoor temperatures can cross 45°C, an air conditioner has to work extremely hard, he explains. "If the cooling isn't keeping up, it usually means there's a gap somewhere, either the system isn't performing at full capacity, or the heat load coming into the home is simply too much for it to handle. It's not something to ignore, especially in summer.”
That 'heat load' can come from several overlooked sources.
According to Dinesh Ramachandran, Technical & SHE Manager at Rentokil Boecker, even a properly functioning residential unit has limitations. Most UAE systems are designed to lower indoor temperatures by only 15°C to 20°C relative to outside conditions. So, during extreme heat, a well-functioning AC may realistically cool a home only to around 26°C.
And several external factors can sabotage performance. Outdoor compressor units placed on balconies under direct sunlight can enter a 'thermal overload' cycle, reducing cooling efficiency. In high-rise buildings, gaps around windows and balcony doors can allow humid air to seep inside continuously, forcing the AC to spend more energy removing moisture rather than cooling the room itself.
Apartments with west-facing glass walls or poor insulation absorb even more heat throughout the day. On top floors, cooled air traveling through hot ceiling ducts can warm up before it even reaches the living space.
In older buildings especially, Seth says residents often blame the AC when the real problem is the building envelope itself.
“Sometimes the AC is perfectly fine, it’s just fighting a battle it was never sized to win,” he says.
Sometimes the AC is perfectly fine , it's just fighting a battle it was never sized to win. Poor insulation, gaps around windows and doors, west-facing glass walls with no window film, a roof with no heat barrier, or even a poorly insulated false ceiling can pump enormous amounts of heat into a home....
The signs you should not ignore
A constantly running AC is one of the clearest indicators that something may be wrong.
“If you’ve noticed that your AC is operating constantly, but never seems to achieve the desired cooling results, it’s a sign of an existing problem,” says Chhabra. Other warning signs include persistent humidity, weak airflow, water leakage around vents, unusual odours, rooms cooling unevenly, or a sudden spike in electricity bills.
Seth adds that ice forming on indoor units, strange noises, or vents blowing lukewarm air can point to issues such as low refrigerant, clogged filters, blocked drainage systems, or failing compressors.
“These won’t fix themselves,” he says. “They need a technician.”
Philip says AC systems in the UAE endure “some of the heaviest use in the world”, with many units running almost continuously for months. Systems older than eight to 10 years without regular servicing are particularly vulnerable to underperformance, especially if they are undersized for the space they are cooling. Due to the region’s extreme operating conditions, he recommends servicing every three months rather than relying on annual maintenance schedules common in cooler countries.
A few things can be checked immediately, recommends Ramachandran, before calling for repairs. If the air feels lukewarm, residents should clean indoor filters and outdoor condenser coils. Heavy-duty weather stripping around balcony doors can help reduce hot air leaks, while blackout curtains can minimise solar heat gain during peak daylight hours.
He also advises switching the AC fan setting to 'AUTO' instead of keeping it permanently on, as continuous fan operation can circulate moisture back into rooms.
Why overheating indoors can affect your health
The discomfort of a warm home goes beyond irritation.
The prolonged indoor heat exposure can strain the body, even when the AC appears to be running. “A home that stays warm despite the AC running creates a low-grade heat stress environment,” says Seth. “You may not feel dramatically unwell, but your body is constantly working to cool itself down.”
That strain can lead to fatigue, dehydration, irritability and poor sleep. Vulnerable groups, including elderly people, children and those with heart or respiratory conditions, face higher risks.
Dr. Spurthy Sirivella, General Practitioner at Medcare Medical Centre Arjan, says many people underestimate how exhausting prolonged indoor warmth can become. “Even when air conditioning is being used, prolonged exposure to warm indoor environments can still place stress on the body,” she says, particularly when humidity levels remain high or ventilation is poor.
The symptoms can include headaches, dizziness, brain fog, irritability and difficulty concentrating. “The body continuously works to regulate its temperature, and this process can become tiring over time,” she explains.
Humidity plays a major role too. Poorly maintained HVAC systems can trap moisture, contributing to mould, airborne contaminants and reduced indoor air quality over time, Chhabra warns.
And this, can particularly affect people prone to allergies or respiratory illnesses.
It might not just be the weather
Sometimes, persistent overheating indoors may point to an underlying medical condition rather than the temperature itself.
Dr. Sirivella says symptoms that improve with cooling, hydration and rest are usually linked to heat intolerance or dehydration. But if symptoms persist, especially alongside chest pain, palpitations, fainting, shortness of breath or unexplained weakness, medical evaluation becomes important. Conditions such as hyperthyroidism, diabetes, anaemia, cardiovascular disease, menopause, obesity and anxiety-related disorders can all affect how the body regulates heat.
Certain medications, including antidepressants, antihistamines and some blood pressure treatments, may also interfere with temperature regulation.
“Listening to the body is important, and ongoing symptoms should not be ignored,” she says. Dehydration can also develop surprisingly easily indoors, even under air conditioning.
“Many people underestimate how easily dehydration can occur indoors, especially in warm climates,” Dr. Sirivella says. “The body can continue losing fluids through sweating, and inadequate fluid intake may lead to dehydration or mild electrolyte imbalances.”
That can trigger headaches, tiredness, muscle cramps and difficulty concentrating, symptoms many people simply dismiss as exhaustion from work or summer stress.
Prolonged exposure to warm indoor environments can still place stress on the body, particularly if ventilation is poor, humidity levels are high, or hydration is inadequate. Many people may experience symptoms such as fatigue, headaches, dizziness, irritability, or difficulty concentrating....
So what should residents actually do?
The first step is understanding whether the issue is mechanical, environmental or medical.
If cooling suddenly worsens, rooms feel humid, airflow weakens or electricity bills spike, it is time for a professional AC inspection. Filters, coils, refrigerant levels and drainage systems should all be checked regularly during summer months.
However, residents should also examine how much heat their homes are absorbing. Blackout curtains, weather sealing, better insulation and reducing direct sunlight exposure can significantly improve cooling performance.
And if fatigue, headaches or dizziness continue despite spending time in air-conditioned spaces, doctors say hydration and medical evaluation should not be overlooked.
