Why is My HVAC Unit Blowing Hot Air

November 2, 2023

We’ve all been there. It’s a hot day, and you want to make your home more comfortable by turning on the AC. But once the HVAC unit kicks on, the cool breeze you were expecting is replaced by hot air. It’s an all-too-common problem for an HVAC system to blow hot air, which can lead to higher energy bills and a less comfortable home.

The good news is that the next time your HVAC system blows hot air, there are steps you can take to figure out what’s wrong. Join the heating and cooling experts at The Unico System as we break down five helpful tips to fix your air conditioning.

1. Make Sure to Change Your Air Filter

If your HVAC unit is blowing hot air, the first thing you should do is check the air filter. AC systems need to have a free-flowing supply of air. Dirty filters limit this flow, causing a strain on the system until it reaches the point where it can’t keep up. It’s crucial to check the air filter at least once a month to see if dust or debris is causing a clog.

On average, you should replace your HVAC air filter every six months. If the air filter is dark grey or you can’t see through the filter at all, it’s time to swap it out for a new one. To ensure you’re using the right filter, check with the HVAC manufacturer to see what’s recommended for the system.

2. Check Your Thermostat Settings

Certain thermostat settings can increase the chances of warm air being circulated through the HVAC system. For many modern thermostats, the “auto” setting can mitigate this. The auto setting allows the fan to push the air through the home when the air conditioner is in a cooling cycle. If your thermostat’s “fan” setting is “on,” it will run all the time – which makes the air feel warm.

3. Defrost the Evaporator Coils in the HVAC Unit

HVAC systems have a condensate drain specially designed to collect the excess moisture while the air conditioning runs. If that drain is clogged, the moisture on the evaporator coils can freeze. When this happens, the blower inside the system overheats, causing the air to get warmer. To fix this, turn the HVAC unit off, clean out the condensate drain, and give the coils time to defrost.

4. Seal Any Leaks in the Ductwork

For homes with traditional wide ducts, it’s common for cracks and holes to develop in these systems over time – thus causing air to leak into the walls. Since older ducts are often put in unconditioned attic spaces, warmer air finds its way in and gets carried throughout the entire HVAC system. To solve this issue, you’ll need to work with an HVAC technician to identify and seal the leaks.

However, upgrading to The Unico System makes this fix far less complicated. Unico’s small-duct system uses insulated nylon ducts that are 100% airtight.

5. Consider Replacing Your HVAC System

If you keep running into issues with your HVAC unit or notice it’s blowing warm air more often, it’s time to consider replacing the unit. Many older air conditioning systems also use freon, which corrodes metal, leaking out and damaging the system. The good news is that you can avoid expensive repairs and make your home more comfortable by upgrading to the right HVAC system.

Find a Unico Preferred Contractor Near You

The Unico System was designed to give you the comfort and efficiency of central air conditioning without any hassle. With small, fully insulated ducts and the flexibility to integrate with smart home thermostats, there’s no better choice for upgrading your HVAC system.

Learn more about how The Unico System can improve the comfort of your home by finding a
preferred contactor near you today!

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