Picture this: you’re dreaming about being on a tropical island. Warm breeze is blowing through your hair. Palm trees are swaying to and fro. And then you hear the seagulls’ squawking slowly turning into a much more familiar sound – it’s your alarm clock. You wake up and realize that the “warm tropical island” you were on is actually inside your home.

At some point during the night, your air conditioner started blowing warm air. And there’s no breeze coming from the ocean or swaying palm trees to cool you off now. Before panicking and thinking that your air conditioner is in need of replacement, check out these five potential causes.

1. Your thermostat isn’t properly set.

Even if you think you switched your thermostat to “COOL” before you went to sleep, check it again. It’s best to rule out the simplest answer for your warm home before moving on to more complex reasons.

If your thermostat is set to COOL and the temperature is set at something lower than “scorching,” then you may be dealing with a more serious problem.

2. Your air filter is dirty.

When was the last time you replaced your furnace filter? And yes, you still need to change this filter even during the summer! It’s what all circulating air in your home passes through, regardless if it’s being warmed or cooled. You need to change your filter as often as your unit’s owner’s manual recommends. This may be once a month, or even more often if you have pets or allergy sufferers in your home.

A clogged, dusty air filter restricts air flow. Issues with proper air flow can result in problems with your compressor. Your compressor is the component in your air conditioner that’s responsible for moving refrigerant through your cooling system. If this vital part isn’t working like it should, the result is a warm, uncomfortable home for your family.

3. A tripped or blown fuse has stopped electricity from getting to your outdoor unit.

If the outdoor unit to your air conditioning system isn’t getting power, your indoor unit is simply pushing out warm, recycled air from inside your house. In simple terms, the indoor and outdoor unit both have to be functioning in order for you to have cooled air inside your home. Check your circuit breaker to see if a fuse has been blown or tripped.

4. Your air conditioner hasn’t been serviced in a long time.

It’s important for you to schedule routine maintenance for your air conditioner each year. During your maintenance appointment, a trained and experienced cooling professional can inspect your unit for potential problems. Also, the tech will thoroughly clean your system to be sure it’s free of any dirt or dust build-up. Dirt and dust restrict airflow and can cause problems with the cooling process in your home.

5. There’s a problem with your return ducts.

If your air filter is clean, your thermostat is properly set, no fuses have been blown or tripped, and your unit has been maintained regularly, and you still have warm air blowing through your system, it may be the result of a problem with your return ducts.

A disconnected or leaky return duct can pull in hot air from the outside environment or your attic space, depending on where it’s installed.

If you are unsure what exactly is causing the air conditioner problem in your home, or if you don’t feel comfortable performing any of the above-mentioned checks, call in a cooling professional to assist you with getting your home back to normal.