BMI Mechanical Heating, Ventilation and Air Conditioning
BMI Mechanical Heating, Ventilation and Air Conditioning

Why Is My AC Blowing Out Warm Air?

▸ May 5, 2021

Is your AC blowing out warm air? If this is the case, you might be able to self-diagnose the issue on your own. 

However, even if you are able to diagnose the issue, you may still need professional help. Whether it’s a residential or commercial AC unit, you need to make sure you correctly identify the issue and safely fix it. Otherwise, you could end up causing more harm to the unit or… causing harm to yourself.

Let’s take a few moments to answer the question, “Why is my AC blowing out warm air?”

Is your thermostat on the wrong setting?

Before you do anything, check your thermostat. This may seem like a no-brainer, but you’d be surprised how many people notice that their ac is blowing warm air and then automatically assume they need to contact an HVAC technician.

Double-check that your AC is not set to heat, that the batteries are working, and that it is set to the correct temperature.

It’s also important to remember that there is a difference between “auto” and “on”, and you should review your thermostat’s guide to make sure you’re using your settings correctly.

Is the airflow restricted?

There are a few reasons you may not be getting the airflow you need in order to get cool air, but typically, it’s a direct result of your vents. Keep in mind, this particular issue can lead to other, more complicated issues. So, if it is restricted vents, make sure you fix it quickly.

Keep Reading: How to prepare your HVAC for summer

Are you having electrical issues?

If your outdoor unit does not have electricity, then this could be the reason why your AC is blowing warm air. Your indoor unit won’t be able to work correctly if your outdoor unit isn’t working correctly. This could be as simple as a blown fuse, but it could be a little more complicated than that. Either way, this usually indicates a larger problem, and it’s recommended that you contact a licensed HVAC company. 

Keep Reading: How to find a commercial HVAC company

Is your unit low on refrigerant?

If your AC is blowing warm air, it could mean that you have a leak somewhere. If this is the case, you’re likely running low on refrigerant — which will ultimately cause that warm air to blow out. In this situation, make sure you contact an HVAC contractor so they can fill up your refrigerant and fix your leak. Failing to fix the leak will simply lead to more warm air later down the line. 

Is your unit dirty?

Without proper HVAC maintenance, your unit could suffer. Dirty filters or coils can lead to buildup, which can mess with the flow of air. Make sure you’re partaking in regular HVAC maintenance — whether in a home or office building — to avoid buildup complications.

Need help with your HVAC unit?

At BMI Mechanical, we provide proactive HVAC maintenance for companies throughout California. We have decades of experience creating greener buildings, preventing HVAC breakdowns, and lowering HVAC repair costs. If you’re interested in learning more about our HVAC services and solutions, give us a call or fill out our online form today.

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A 15% reduction in energy consumption can lower operating costs by $12,000 per year for every 50,000 square feet of space. Linc

BMI’s corporate mantra of ‘Where Better Really Matters’ is not only true, but stringently adhered to by their staff. The typical less onerous route of letting someone else deal with an obvious warranty issue would have been the reaction by a number of service companies, especially over a holiday period. The perseverance of BMI’s staff speaks volumes about the company’s integrity and capabilities. Charles J. Gill President Integrated Service Group, Inc.