Why Is My Brand New Window AC Not Cooling? [Causes & Fix]

Blog, Electrical & HVAC

No one wants a broken AC; it gets even more frustrating when the AC is new. You end up asking the question, “why is my brand-new AC window not cooling?” Or “how do I fix it?”

There are many reasons this could be, but the most obvious reason is that it is in the wrong mode. However, your new AC window may not be cooling for other reasons—for example, a damaged compressor, clogged filter, etc.

In this article, I will highlight all the possible reasons why your brand-new window AC is not cooling. I will also write about how you can fix it.

Why is my brand-new window AC not cooling? [Possible reasons]

1. Your window AC is in the wrong mood

Your new window AC may not be cooling because of a simple reason. This is because it has been set in the wrong mood. This is usually the reason a majority of the time.

Yes, there are different brands of window AC, and a majority of them come with three modes; Cool Mode, Fan Mode, and Dry Mode. Each mode serves a particular purpose. To help you out, I will explain these three modes briefly.

Cool mode: Cool mode removes heat in the room until it reaches the temperature set on the AC thermostat. Once this temperature is reached, it works to maintain it.

Fan mode: The fan mode allows the AC to function as a typical household fan. It does not create any cold air but facilitates good airflow.

Dry mode: Dry mode is otherwise known as the Dehumidifier, although not all window AC has this mode. Its job is to remove moisture from the air or dry it out.

What you should do?

Simply check which mode your window AC is on. If it is on another mode, try putting it in cool mode and assess how things change. But if the situation remains the same, the issue might be any of the others I will list. So, keep reading.

2. Broken compressor

The window AC compressor’s work is to suck out hot air from the home and dump it outside. In other words, it makes cold airflow; if damaged, the AC won’t work properly.

This problem might have originated during the shipment of the AC. It could be that they used a small box to contain the AC, or the cushioning material in the container wasn’t enough.

What you should do?

There are two possible moves, the first being to replace the compressor entirely. However, replacing the compressor tends to be very expensive. The second move is to look at the return policy for the air conditioner to see if you can return the appliance since you received a faulty one.

3. The AC filter may be dirty or clogged

Generally, the AC filter is supposed to be cleaned occasionally (although it is not a must). If the filter is dirty or clogged, it might restrict the airflow, preventing the AC from cooling.

What you should do?

You can have the AC filter cleaned, or you can replace the filter. You can contact an expert to help remove any material clogging the filter. They can also help you replace the filter if they notice it is damaged.

4. Faulty thermostat

The thermostat works to monitor the temperature of the room. Once it detects that the temperature has dropped, it hints to the compressor to start or stop the cooling cycle. If the window AC thermostat is defective, it may not cool or may cool continuously.

What you should do?

Have a professional inspect the thermostat to see if there is any wear and tear or any disconnection. If damaged, he/she can help you change the thermostat.

When should you change an air conditioning unit?

The rule of thumb is generally after ten years. However, if the AC unit is occasionally piling up billing for repair, it would be best to consider changing it entirely.


How much does it cost to replace a window AC?

Replacing a window AC unit costs anywhere from $150 to $500.

Can the window AC be repaired?

Yes, it can. You can repair a window AC unit with the right components and expertise.

Conclusion – Why is my brand new window AC not cooling?

The most common reason is that the window AC has been set to the wrong mode. It could also be that the compressor is damaged, the AC filter is clogged, the thermostat is faulty, etc.

Most of these issues can easily be solved; others may require replacing the window AC entirely. This article highlights the possible reasons and what you should do for each.

I believe this article was helpful. If it was, visit Samkinsconstructions today for more articles that you might find useful.

Thanks for reading.

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