What To Do If Your Air Conditioner is Not Cooling Your Room

There’s nothing more frustrating than turning on your air conditioner, expecting a cool blast of air − only to be left sweating in a warm, stuffy room. If your AC isn’t doing its job, don’t panic just yet.

There are several common reasons why it might not be cooling properly, and many of them are easy to troubleshoot on your own. Sometimes it’s something simple like a dirty filter or incorrect settings.

Other times, it might signal a bigger issue that needs a professional technician’s touch. Either way, getting to the root of the problem quickly can save you time, money and discomfort.

In this blog, we’ll walk you through what to check, how to fix minor problems, and when it’s time to call in the experts. Let’s get started.

Check the Thermostat Settings

Before diving into complex troubleshooting, start with the simplest step − check your thermostat. It sounds obvious, but you’d be surprised how often the settings are the culprit.

Make sure the thermostat is set to “cool” and not just “fan” or “auto”. If it’s on the wrong mode, your air conditioner might be running but not actually cooling the air.

Next, take a look at the temperature setting. If it’s set higher than the current room temperature, the AC won’t kick in. Try setting it a few degrees lower and see if anything changes.

Also, check that the thermostat hasn’t been accidentally bumped or changed by someone else in the house. If you have a programmable thermostat, ensure the schedule isn’t interfering with your comfort.

Still no luck? Try replacing the batteries or resetting the unit. Sometimes, it’s all about the little things.

Clean or Replace the Air Filter

A clogged air filter is one of the most common reasons your air conditioner isn’t cooling properly. When the filter gets dirty, it restricts airflow, making it harder for cool air to circulate throughout your room.

Luckily, this is an easy fix. Here’s what to do:

• Turn off your air conditioner before handling the filter to stay safe.
• Locate the air filter – it’s usually behind a vent cover or inside the indoor unit.
• Check the condition of the filter. If it’s covered in dust or debris, it’s time to clean or replace it.
• Clean reusable filters by rinsing them under cool water and letting them dry completely.
• Replace disposable filters with the same size and type.

It’s a good habit to check your filter every month during heavy AC use. A clean filter keeps your system running efficiently and your home feeling cooler.

Inspect the Outdoor Unit

If your split system air conditioner isn’t cooling properly, it’s worth taking a look at the outdoor unit − also known as the condenser. This part of the system plays a big role in getting rid of the heat from inside your home. If it’s dirty, blocked or damaged, the entire cooling process can slow down or stop altogether.

Start by visually inspecting the unit. Is it covered in leaves, dirt, or debris? If so, turn off the power and gently clean around it. Make sure there’s at least half a metre of clear space all around the unit so it can “breathe”.

Also, listen for any unusual sounds coming from the unit. Rattling or buzzing noises could point to a mechanical issue or loose parts. If the fins look bent or the fan isn’t spinning, it’s time to call in a heating, ventilation and air conditioning (HVAC) professional. A quick check now can save you from a bigger repair later.

Look for Refrigerant Leaks

Refrigerant is the chemical that cools the air in your AC system. If your air conditioner is low on refrigerant, it won’t be able to cool your room effectively.

Unlike fuel in a car, refrigerant doesn’t get used up – so if levels are low, there’s probably a leak. Here’s what to look for:

• Warm air from the vents – even when the system is running.
• Hissing or bubbling sounds coming from the indoor or outdoor unit.
• Ice forming on the refrigerant lines or evaporator coil.
• Higher energy bills without a clear reason.

If you suspect a refrigerant leak, don’t try to fix it yourself. Handling refrigerant requires special tools and a license.

• Call a licensed technician to locate and repair the leak.
• They’ll also top up the refrigerant to the correct level and check the system is safe and efficient.

Catching leaks early can prevent bigger, costlier problems.

Check for Blocked or Leaky Ducts

Even if your ducted air conditioner is working perfectly, blocked or leaky ducts can stop cool air from reaching your room.

Over time, dust, debris or even pests can build up inside your ductwork, restricting airflow. Or, if there are gaps or holes in the ducts − especially in the attic or crawlspace − cool air could be escaping before it ever gets to you.

If you’ve noticed weak airflow from your vents or uneven cooling throughout the house, duct issues might be the reason.

While some minor blockages can be handled with a vacuum and a vent cover removal, it’s often best to have a professional inspect your ductwork. They can check for leaks, clean out buildup, and reseal any problem areas.

Fixing duct issues not only helps your air conditioner cool better − it also improves efficiency and lowers your energy bills. It’s a win-win for comfort and your wallet.

Evaluate the AC Unit’s Size and Age

Sometimes, your air conditioner isn’t the problem − it just might not be the right fit for your home. If your unit is too small or too old, it may struggle to keep your room cool no matter how well it’s maintained.

Here’s what to consider:

• Is the AC unit properly sized?
  • A unit that’s too small won’t have the power to cool the space effectively.
  • One that’s too big can short-cycle, turning on and off too frequently without properly dehumidifying.
• How old is your system?
  • Most AC units last around 10-15 years.
  • Older units often become less efficient and may not cool as well as they used to.
• Are your energy bills rising?
  • This could be a sign the unit is overworking to keep up.

If your AC is outdated or undersized, it might be time to consider a modern, energy-efficient upgrade.

Call a Licensed Technician

If you’ve gone through all the basic checks − like the thermostat, filters, and outdoor unit − and your air conditioner still isn’t cooling, it’s time to call in a licensed technician. Some issues, like refrigerant leaks, electrical faults or failing compressors, require expert knowledge and tools to fix safely and properly.

A qualified HVAC technician can run a full system diagnosis, pinpoint the root cause, and get your AC back in working order. They’ll also check for any hidden problems that could lead to bigger (and more expensive) issues down the line.

While it might be tempting to keep troubleshooting on your own, attempting complex repairs without the right skills can be risky and might even void your warranty.

Sometimes, the smartest move is to let a pro take over. It’ll save you time, hassle, and ensure your air conditioner runs efficiently and safely all season long.

Stay Cool and Don’t Sweat It

If your air conditioner isn’t cooling your room, don’t sweat it − literally. Start with the simple stuff like checking the thermostat, cleaning or replacing the air filter and making sure the outdoor unit isn’t blocked.

Sometimes, a quick DIY fix is all it takes to get things running smoothly again. But if you’ve tried the basics and your room still feels like a sauna, it might be time to call in a professional HVAC technician. Issues like refrigerant leaks, duct problems or an outdated unit need expert attention.

The sooner you get to the root of the problem, the sooner you can enjoy a cool, comfortable home again. Regular maintenance can also go a long way in preventing future issues.

So stay cool − literally and figuratively − and give your AC the care it needs to keep you comfortable year-round.

Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.