How To Tell if 2-Stage AC Is Actually Working?

Single-stage air conditioners used to be the norm, but nowadays, two-stage air conditioners are becoming more common. So, now that you’ve installed your two-stage air conditioner, how can you tell if it’s working?

Your two-stage air conditioner works when an even temperature is maintained for an extended period. You’ll also notice less moisture and humidity in the air. You can also record the amp level to check if the AC maintains the temperature when it shifts into the second stage. 

This article will help you check your air conditioning system to ensure that your air conditioner is working properly and shifting into the second stage. I’ll also offer tips on what to do if your two-stage AC isn’t working properly. 

Signs That Your Two-Stage AC Is Working Properly 

Often, it can be difficult to know if your two-stage air conditioner is working properly or whether it’s only working on one stage, especially if the temperature is too hot. If you’ve just installed a two-stage AC, it will take time to figure out how it works. 

Here are some signs that your two-stage AC is working properly: 

The Indoor Temperature Remains Stable

If you feel that the temperature is stable with less fluctuation, you’ll know that your two-stage air conditioner is working properly. 

The two-stage air conditioner provides consistent temperature control and won’t wait for the temperature to drop significantly before reactivating the cooling mechanism. Because of this, you won’t notice the average room temperature deviating much from what you set it on. 

Unlike the one-stage air conditioner, which works up to the pre-set temperature on the thermostat and then turns off, your two-stage air conditioner will smoothly reach the pre-set temperature at a more consistent pace. You’ll also feel the cooling effect for longer. 

Read: What Are Types Of HVAC Systems In Apartments?

The Air Humidity Levels Drop

Another factor that will help you identify if your two-stage AC is working is the humidity level. When your two-stage air conditioner works, there will be less moisture in the air, and the humidity levels will drop. 

Due to its extended run times, the two-stage air conditioning system has a variable speed compressor that dehumidifies indoor air more effectively than a single-stage unit. 

Have a Question? Ask HVAC Technician

Click here to use the chatbox to speak with one of our technicians.
No in-home service calls. No appointments.

The main difference is that single-stage units don’t run consistently, and the humidity levels will increase even when the temperature remains consistent. 

To check if your two-stage AC is working, you can use a humidity testing kit, check the humidity level on your thermostat. However, not all thermostats will show the current humidity level. 

If the temperature drops but the humidity level remains stable, there could be something wrong with the second stage feature on your AC. 

Read: Do I Need A Furnace With A Heat Pump?

The Air Conditioning Has a Consistent Speed 

You’ll know your two-stage air conditioner is working when the speed of the air conditioning system is consistent. You’ll have to measure and compare the amp draws of your AC to check this. 

You can hire a professional HVAC technician to check this for you.

If you have some experience with HVACs, you can check out this video. It explains how you can verify that the second stage works in any two-stage equipment: 

Before automatically shutting off, a single-stage compressor blasts chilly air around your house. When the temperature inside rises, it then comes back on.

Most of the electricity usage by your air conditioner happens when it first comes on, not while operating.

On the other hand, a two-stage air conditioner gradually cools the air and won’t wait for the temperature to decrease significantly before restarting. While you can manually check for fluctuations in the airflow, you should call a professional to confirm if you suspect that there are fluctuations in the AC’s speed. 

So, if you notice the AC running slower than usual or suddenly blasting cool air, there may be something wrong with its settings, or it may not be functioning properly. 

Read: Two-Stage Furnace Disadvantages

The Two-Stage Compressor Is Running 

Your two-stage air conditioner has two compressors that should run when the AC is working properly. When either compressor malfunctions, you’ll notice a significant change in cooling. 

If your AC doesn’t cool the air initially or takes too long to do so, it may be a sign that the first-stage compressor is damaged

If the temperature drops to a certain level but doesn’t go below this, it’s a sign that the second-stage compressor is damaged

Two-stage units run more consistently than single-stage units, so if you notice that the air conditioner cools the room quickly and then evens out, it means both compressors are working. 

Read: Pros And Cons Of A Modulating Furnace

What To Do if Your Two-Stage Air Conditioner Isn’t Working?

If your two-stage air conditioner isn’t working or only one-stage cooling is working, the problems could range from minor electric faults to compressor issues. If you suspect something is wrong, you can reset the thermostat, fix other minor issues or call a professional. 

Reset the Thermostat 

The best way to fix an AC that’s not working is to reset the thermostat to factory settings. Using the AC on cooling when the outdoor temperature is too cold, or vice versa, may affect the unit’s performance. 

You can also reset the AC to factory settings with the remote. This process is different depending on your AC’s model. 

If resetting the thermostat doesn’t work, something else may be wrong with your AC. In such cases, you’ll have to pinpoint the issue before addressing it. 

Read: Top 5 Common Problems With Two-Stage Air Conditioners You Need To Know

Fix Minor Faults 

Depending on your expertise with AC units, you can fix minor issues such as wiring problems, dirty air filters, or a blocked vent. However, if you encounter a major problem, it’s best to call a professional.

Service your air conditioner regularly and do seasonal maintenance if you experience cooling problems. You’ll be surprised how much a dirty air filter can affect your two-stage AC’s cooling

However, don’t attempt repairs if you aren’t experienced enough or don’t know what’s the main problem. 

Call a Professional 

If your AC has a compressor problem, gas leak, or other major problem, you’ll have to call an HVAC professional to fix it. If you have time left on the warranty, it’s best to contact your supplier or the company that installed the unit since compressor problems can be expensive to repair. 

Avoid trying to fix these problems yourself, or you’ll permanently damage your AC! 

Get an Automated Thermostat 

If you aren’t sure how to set the temperature and humidity levels in your two-stage air conditioning unit, get an automated thermostat that will make this step easier. 

Automated thermostats also have digital settings that allow you to monitor current humidity levels, which help you pinpoint problems with the two-stage system. 

So, if you aren’t sure whether your AC is functioning properly, an automated thermostat is the ideal solution, as it will help you determine the efficacy of your two-stage AC.

Final Thoughts 

Two-stage air conditioners are designed with more effective cooling systems and can help you save on electricity costs. However, it’s often difficult to know when one stage isn’t functioning properly. 
Always check the cooling effectiveness, airflow speed, and humidity levels for problems. In most cases, the problem may be minor, such as wrong thermostat settings. However, if it’s a major problem, call a professional.