6 Reasons Why AC Compressor Not Working But Fan Is Running

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If you want your AC to function efficiently and at the same time remain in good condition, then it is necessary to find out any issue you’re encountering. Now, in this case, if you notice that something’s wrong with your AC compressor, it is important to take note of it and diagnose the issue. 

Moreover, there are also times when you’ll find that an AC compressor is not working, but at the same time, a fan is running. So what is the reason behind this issue, and is there a way to solve it? You might want to read on to know more about it. 

What Does an AC Compressor Do?

Before you go ahead with diagnosing the main problem within your AC compressor, you might want to know what it does for better understanding. 

First of all, it is imperative to know that an AC’s compressor is one of its most important parts. If it is not working correctly, your house probably won’t get the required cooling.

An AC compressor is required to pump or transfer the refrigerant across the entire AC system. A refrigerant is a type of liquid that helps to absorb heat from the inside of your home and carry it outside. 

Hence, in short, an AC compressor is responsible for the transfer of refrigerant and removal of heat from the indoors of your house.  

What Does an AC Fan Do?

Another important part of an AC is an AC fan. An AC fan is responsible for the movement of air. Hence, its job is to pass the hot air present inside the room to move outside and facilitate the proper circulation of cool air through the ducts and then into the rooms. 

So, if we see both the AC fan and compressor’s function together, it goes something like this: The fan passes the hot air to the compressor coils such that the air is converted into cool air. 

Now, if there is a problem with an AC fan, it can cause an inadequate transfer of air and affect your air conditioner’s performance and efficiency. 

6 Reasons Why an AC Compressor to Stop Working

If your AC compressor has stopped working even if the fan is running, then look out for the main causes given below: 

1. AC Filters or Coils Are Dirty

Dirty AC filters and coils are one of the main reasons why your AC compressor stops working. 

It is because the AC filters are required to pass clean and filtered air. However, if they are dirty, dust and other debris can get to the compressor coil and affect its functioning. 

Moreover, dirty AC filters also significantly affect the flow of air. Hence again, if there’s reduced airflow, it can cause issues with the evaporator coil. 

Also, let’s not forget that your compressor has to work more to function properly. This can cause the overheating and automatic shutdown of the compressor. In the worst cases, it can even severely damage your compressor.

So, make sure that you regularly clean or replace your AC filters to reduce any potential damage to your compressor. 

2. Issues With Thermostat

Have you considered that the issue might not just be with your compressor but rather with the thermostat? 

For instance, if the thermostat shows that the required temperature has already been reached in the room, then your AC’s compressor won’t start either. Hence, in this situation, simply adjusting the thermostat setting can also solve the problem. 

However, if the problem is in its internal working, your thermostat must be either replaced or repaired. 

3. Issues With Electrical Power

There’s also a high possibility that your AC’s compressor unit just isn’t getting the electrical power required to function. 

For instance, if you see that the fan is running but the compressor is not, it is highly possible that the outdoor unit isn’t getting power. On the other hand, as the fan is located in the indoor unit, it might be getting power. 

So, consider checking for any blown fuses or circuit breakers. 

4. Units Are Mismatched

This point is only applicable if you have recently replaced any of the two units, either indoor or outdoor. 

Now, keep in mind that the entire air conditioning system is built with proper planning and architecture. However, if you have replaced one unit, i.e., outdoor unit, with another one, then there’s a high chance that both the outdoor and indoor unit aren’t matched properly. 

In this case, too, you’ll encounter problems with your AC compressor. So, consider calling up an HVAC technician to get this checked. 

5. Capacitor or Starter Relay Problems

The capacitor and starter relay of any AC compressor are two of the most important components. 

The capacitor is responsible for providing power to the compressor to start working, whereas a starter relay transmits this power from the capacitor to the compressor.

So, it is also possible that the capacitor isn’t working. Thus, causing the compressor to shut down. 

6. Dead Compressor

Your compressor might break down in the worst-case scenario due to various reasons like: 

  • Refrigerant problems
  • Inadequate compressor oil 
  • Electrical problems 

In this case, you will have to get a new compressor and someone to install it, which can get pretty expensive. 

How Do I Know if My AC Compressor Is Not Working?

There are certain signs you might want to look out for to know whether your AC compressor is working or not: 

  • Compressor shutting down completely when you turn on AC 
  • AC giving out warm air instead of cool air 
  • The outdoor unit is vibrating when AC is turned on
  • The outdoor unit is producing strange noises
  • The circuit breaker keeps tripping 

So, if you come across any of the above signs, make sure to get your AC compressor checked or try checking it yourself. 

How Do I Test My AC Compressor?

There are a few steps that you can follow to test your AC compressor. This includes: 

1. Turn off the power and let the AC unit cool before you start testing. 

2. Get a multimeter and set it to ‘continuity.’

3. Place the red pin of the multimeter to the C pin of the compressor. Similarly, place the black pin to the S pin of the compressor.

4. If you get a reading of more than 30 ohms, then there’s some issue with the compressor.

This way, you can test your AC compressor for any faults. 

How Do I Reset My AC Compressor?

If you want to reset the AC compressor, you have to reset the whole unit. Here’s how you can do it: 

  • Turn the thermostat and then turn off the AC. 
  • Locate the circuit breaker box. Then, turn it off too. 
  • Keep everything turned off for exactly 60 seconds or 1 minute. During this time, your AC, as well as the compressor, will reset automatically
  • Turn the AC on and wait for some time to see whether cool air is coming or not.

Should I Replace the AC Compressor or Buy a New Air Conditioner?

Let’s not ignore the fact that replacing an AC compressor is an expensive task. It can cost quite a lot, and along with that, you also need to pay for labor. 

Hence, the question arises – which one to go for? Should you replace an AC compressor or buy a whole another air conditioner? 

First of all, make sure that the AC compressor is broken and can’t be fixed with some repairing or other work. For this, consider calling a technician. If you find that it requires replacing, consider two things: 

  • Do you have any warranty left? 
  • The cost of replacing in comparison to buying a new AC 

Another thing to keep in mind is that even if you replace your compressor, you might have to change the whole outdoor unit. If the outdoor mismatches the indoor, you’ll again face a lot of issues. 

Hence, if you feel like the cost is getting too much or the AC has become too old, then you might want to buy a new AC. 

How Do I Prevent AC Compressor From Not Working Even If the Fan Is Running?

Lastly, there are certain ways to prevent an AC compressor from not working even if the fan is running, such as: 

1. Clean the Air Filters and Condenser Coil

First of all, you might want to either clean the air filters (if reusable) or replace them regularly. You also need to clean the condenser coil. 

To clean the condenser coil, you need to locate it and then use water and spray-on condenser cleaner. These will help in cleaning up all the dust and debris.

2. Check the Refrigerant Levels

If your AC is working well, then the refrigerant levels are supposed to be proper. However, if there’s an issue, such as leaks, it can cause the levels to decrease significantly. 

Now, in this case, you need to ensure that these levels are regulated. If they are not, then the wear and tear on your AC compressor may increase. This could lead to potential damage. 

3. Regular Maintenance is a Must

If possible, your AC system needs to get regular maintenance. For instance, replacing air filters every month when AC is used frequently, cleaning the outdoor unit properly, and even lubricating and cleaning the fan. 

This will ensure that your AC remains in top-notch condition. 

Final Thoughts

To conclude, your AC compressor is an integral part of the unit. If it breaks down, then the whole system won’t work efficiently. Hence, try to diagnose the problem and find a suitable solution using our guide. 

If you still can’t find the problem, contact a technician to help you out.