Your AC fan not turning off means it will be consuming more power making your electrical bills shoot up. It will also make you worried as you’ll try gauzing where the problem could be. Additionally, it will also be making your house uncomfortable to stay in as it might be too cool from a continuous operation.
When your AC fan runs continuously without shutting off, it could be due to frozen evaporator coils or a dirty air filter. This problem can also be because of clogged condenser coils, a faulty relay switch, an issue with the thermostat, or low refrigerant levels.
All these are problems you can easily solve without the help of a technician. For example, clean a dirty air filter or condenser coils. So, read on and get an in-depth explanation of the causes and solutions to an AC fan that can switch off.
Clogged Condenser Coil
One of the reasons your AC fan can fail to switch off is dirty condenser coils. Usually, hot air passes through the evaporator coil, where it extracts the heat. After that, the heat will move to the next part with the help of a refrigerant, where the compressor pressurizes it before going to the condenser coil. The condenser coil will help the unit to release heat into the atmosphere.
During this process, the dirt and dust in the air will remain on the condenser coils. This will interfere with its normal functioning, and it will not extract the heat from the refrigerant. As a result, your air condenser’s coils will have a blockage that will reduce the airflow in the fan. So, it will struggle to keep working with the restricted airflow to help cool your room. Your AC fan will, in this case, not switch off but rather try its best to ensure your house remains conducive to stay in.
The Fix: To solve such a problem, you need to clean your AC’s condenser coils. You can do this with a soft brush. But then ensure you do it carefully as this is a delicate part of the AC fan that can get spoilt easily. When this happens, the refrigerant will leak and eventually force you to replace the condenser coils, which can be costly.
If you want to avoid experiencing this problem regularly, make it a habit of cleaning your condenser coils at least once a year. Alternatively, you can keep your AC fan away from foliage or plants to avoid dirt accumulation.
Thermostat Problem
Another reason why your AC fan won’t switch off is because of a faulty thermostat. If your AC’s thermostat is defective, it won’t detect when the room is at the desired temperature. This can be because of high dirt accumulation on the thermostat’s sensor.
Or when there’s an electrical problem in the wiring connection like loose wires, which interferes with smooth communication between the AC and thermostat. If it’s a wiring issue, call your technician to help you out if you’re unsure how to go about it.
Wrong Thermostat Settings
At times though, the issue may be a wrong setting on the thermostat. It could be that you unknowingly changed the setting from ‘auto’ to ‘on’ or to low-temperature settings. Because of the low-temperature setting, your AC fan will struggle to work and keep the room cool, and this will make it not switch off. You need to change the setting from ‘on’ to ‘off’ or ‘auto.’
Dirty Filters
If your AC’s filters are dirty, then it will not function properly. Remember the air filters are responsible for cleaning the air from the evaporator coils. But after some time, the dirt will accumulate on the filters, and you should clean it out.
This you should do after some operational hours like once a day. If you don’t clean the air filters, it will strain to work resulting in low airflow. It may at times also overheat and cause other problems too. When this goes on for long, your AC fan will have to struggle to keep up working to give you cool air. You can replace the air filters or clean them if they’re still in perfect shape.
Low Refrigerant Levels
Ac fans use a vapor compression cycle to help control the temperature of the room. So, this indicates that the refrigerant in this process doesn’t get used up. Instead, the refrigerant keeps converting from gases to liquid within the lines.
But when the refrigerant level reduces because of leakage between the lines, your fan won’t work as usual. This will result in a short cycle because of low-pressure levels within the line. Your AC fan, in this case, won’t shut down as it tries to maintain the cycle and keep the house cool. If you’re not careful, this can damage your fan or make it consume a lot of electricity.
The Fix: You can solve this by identifying the leaking area either where there’s a scratch or bend. Then repair that leakage and add refrigerant through the suction line. Ensure the refrigerant you use is compatible with your AC, and only do this if you’ve prior knowledge about it. However, working with your technician can be the best solution here.
Frozen Evaporator Coils
Another reason that can make your AC fan not shut off is frozen evaporator coils. Frozen evaporator coils are because of condensed air that settles around this area. With time this will be a huge ice build-up that will result in air blockage and affect how your AC fan works.
If this is not corrected on time, it will lead to refrigerant leakage and won’t filter out heat. Also, the AC’s vents will become hot and make your house have unfavorable temperatures. To avoid this, your AC fan will try its best to restore its normal function and not shut off.
The Fix: To solve this, ensure your AC is not near any obstructions like furniture or plants. These objects can cause restricted airflow, making your AC keep working to make your house cool. But you can also check if there’s any spoiled or dirty part that can alter unrestricted airflow then repair them.
You Might be Using the Wrong Size of AC Fan?
Your AC fan may not be able to switch off because it’s not the right size for your house. Remember, before you buy a fan, you need to consider the size of the room you’re going to use it on. Through this, you’ll get the right AC size that will meet your cooling demands.
If you’ve got a smaller AC fan for a bigger room, it will not be capable of meeting your cooling desires. Instead, it will consume extra energy and keep running for a long without delivering the right temperature. This is also applicable when you’re using a bigger fan in a smaller room.
It’s advisable to be keen on the BTU ratings of the AC fan you’re to buy. With this, you’ll get an ideal AC that’s ideal for the size of your room. But don’t go for a lower or higher BTU rating if you’ve got a smaller room and vice versa. Doing this will make your ac fan overworked as it tries to meet your desired indoor temperature.
So, measure the room’s size in square feet to act as your guide while buying. Also, consider the number of occupants in your house and the ceiling height as they determine the size of AC fan to go for.
Could It Be an Electrical Issue?
If your AC fan doesn’t switch off, this could result from an electrical issue with one of its components. For example, a faulty relay will keep supplying the AC with power making it not shut off.
It could also be an issue with a burnt wire, or the capacitor could be interfering with the power supply. When this is the case, your ac fan will keep running in a bid to cool your rooms down without success.
The Fix: The solution to this is checking if there’s any problem with any electrical connection. If it’s the switch, you can fix this yourself or work with a technician if it proves to be more problematic.
Bottom Line
If your AC fan doesn’t switch off, it could be having a clogged condenser coil or air filters. Another reason could be the wrong thermostat setting or if it’s faulty. But frozen evaporator coils or low refrigerant levels can also cause this issue.
Some of these things you can comfortably rectify without the help of a technician. However, if you feel they’re beyond your knowledge, contact your HVAC technician and get the best solution.
