Is It Ok To Run Car A/C While The Heater Is On – yes or no

You may have heard that there are better ideas than using the heater and air conditioner simultaneously. But what’s this? That’s not exactly accurate! There are a few good reasons to consider combining them, especially when the weather is chilly. 

Yes, it’s OK to run the car AC while the heater is on, as it helps dehumidify the air and prevent moisture-related issues. The AC removes moisture, aiding in defrosting and preserving the car’s interior.

In this article, we will describe whether running the car AC while the heater is on is good or bad, so stay with us! It will be beneficial for you.

When Is It Beneficial To Use Both AC And Heat At The Same Time?

Running the heater and the air conditioner together may seem strange at first, but there are instances when this out-of-the-ordinary coupling can be beneficial. Let’s examine when and why it makes sense to operate both AC and heat simultaneously.

1. Remove Moisture:

Something interesting happens when you operate the heater and air conditioner together. The air conditioner removes moisture in addition to cooling the air. Consider having a cup of cold water outside on a warm day.

Water droplets start to gather on the cup’s outside. That almost resembles what transpires in the humid air. The air is made to feel less wet by the A/C’s assistance in removing the additional moisture.

Remove Moisture
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Even though the air grows warmer when you use the heater, it could still feel slightly moist. It would help to have the A/C chill the air to remove the moisture effectively.

It is significant because moisture issues like mold growth and foggy windows might arise. Therefore, utilizing the A/C in addition to the heater keeps things dry and comfortable.

2. Upholstery Protection:

Glue may be used to hold your car’s interior together, including the upholstery. Over time, high humidity levels might degrade the glue’s hold, possibly leading to certain upholstery pieces coming away.

Future expensive repairs may result from this. Combining the power of the AC and heater can assist in maintaining a stable level of humidity, extending the lifespan of the adhesive, and avoiding problems like these.

3. Cold Weather Comfort:

It makes sense to turn on the heating in your car’s interior when the weather turns cool. However, relying entirely on the heater might make the inside of the automobile uncomfortably humid.

Cold Weather Comfort
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The AC steps in as an unexpected ally in this situation. Running the air conditioner in tandem with the heater can help to dehumidify the space, preventing that musty smell and improving the cabin’s comfort.

4. Preventive Measures For Rust:

Did you know that metals can begin to rust without obvious water puddles due to high humidity? If you use the heater too much in the winter without an air conditioner, the inside may become wet, resulting in slightly damp metal components like brackets and tracks.

This moisture can eventually cause corrosion. You can successfully lower humidity levels by turning on both the AC and the heater, which reduces the possibility of rust formation. It is beneficial for components that are concealed from view, like seat foundations or sliding mechanics.

5. Longevity And Value:

You’re making an active effort to preserve the value and longevity of your car by utilizing the AC to dehumidify the interior. If you keep your car inside in good condition and avoid rust and upholstery problems, it will be more desirable to purchasers if you ever decide to sell it.

Longevity And Value
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How To Switch Safely Between Your AC And Heater?

1. Timing Is key:

Allow your system to complete its current cycle before you even consider switching from the heater to the air conditioner or vice versa. Interrupting it in the middle of its process will waste energy and possibly even confuse your HVAC system. Consider it as finishing one activity before beginning another.

2. The Auto Mode Advantage:

Your thermostat’s “auto” mode can make all the difference. Your system finishes its cycle when you select “auto,” and it then waits for the appropriate moment to switch to the opposing mode. It ensures a smoother transition between the heater and air conditioner and prevents unexpected energy surges.

 The Auto Mode Advantage
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3. The Five-Minute Rule:

Ensure that your system has some breathing room. Wait at least five minutes before switching between the heater and air conditioner after your current cycle is finished. This brief pause enables your system to completely reset and recalibrate, preventing any sudden adjustments that can strain your HVAC system excessively.

4. Gradual Temperature Changes:

When it comes time to move between cooling and heating modes, be careful when adjusting the temperature, and avoid making significant modifications because doing so can cause your system to cycle quickly, placing undue strain on its components and raising energy consumption.

 Gradual Temperature Changes
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5. Say No To Short-Cycling:

Short-cycling, or frequently switching between the AC and heater, is bad for the health of your system. It makes your HVAC system work harder, which can hasten the deterioration of crucial components like fans and compressors. In order to ensure that your system performs effectively and lasts a longer time, aim for greater gaps between switches.

Say No To Short-Cycling
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6. Embrace Balance:

Just keep in mind that your heater and air conditioner are not competitors. They can cooperate to keep you comfortable. It’s important to strike the correct balance between these systems based on your comfort requirements and the weather.

Here Are Some Steps To Take If Your Compressor Locks Up:

It can be confusing to deal with a locked-up compressor in your HVAC system, but don’t worry; there are feasible options you can use before thinking about a complete replacement. Here is a practical way to assist you in overcoming this obstacle:

1. Check For Leaks:

There’s a risk that a leak could be the source of the issue if you’ve recently replaced HVAC unit components like a condenser or evaporator coil. Disconnect the compressor’s refrigerant lines to conduct an investigation, and while your air conditioner is running, watch for bubbles.

The presence of bubbles indicates a leak. Reconnect everything and check to see if the compressor starts up again if you are certain there are no leaks.

2. Inspect Wiring Connections:

Locking up a compressor can occasionally be brought on by loose wire connections. If you have experience working with electricity, you can thoroughly inspect for any loose connections. To avoid potential risks, it is best to get professional assistance if you are unsure of your electrical abilities.

Inspect Wiring Connections

3. Avoid Forcing It:

In the event that your compressor becomes stuck, resist the desire to restart it. Making a blocked compressor run can make things worse and cause more problems. Instead, follow the instructions below or speak with a professional.


1. Should I Run My Car AC In The Winter?

Running your car’s air conditioning occasionally can extend its lifespan and offer significant winter safety advantages.

2. What Happens If You Run The AC In Winter?

Running the air conditioner in the winter might result in frozen coils and extensive moving part damage. Most manufacturers advise against using air conditioning when the temperature drops below 60 degrees.

3. Do You Turn Ac Off For The Heat In The Car?

In most cars, the air conditioning should always be on (even in the cold). The A/C and heating are typically designed to work together in most vehicles. The evaporator coil (below the dash) removes moisture from the air when you run the air conditioner and heater simultaneously.

4. What Does The A/C Button In A Car Do When The Heater Is On?

The A/C button turns on the compressor. All it does is that. The compressor is now prepared to turn on to cool the vehicle’s interior if necessary.


While using the heater and air conditioner simultaneously may seem strange, there are times when it makes sense to do so. When it gets cold outside, and you’re tempted to only use the heater, keep in mind the advantages of combining it with the air conditioner. You may improve comfort while reducing rust and maintaining the quality of your car’s interior by dehumidifying the inside. For a balanced and well-maintained driving experience, consider inviting the AC to the party the next time you reach for the heater dial.

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