On any given day, we depend on the AC to give us a cool breeze during hot weather and help in balancing the home or office thermostat during the colder seasons. There are a lot of problems that could come with AC units but when they cannot be turned on, it becomes a source of panic. With this, it pays to know why the air conditioner is not turning on so that the most immediate solution could be done.
In this post, some of the most common reasons as to why an air conditioner does not turn on are revealed. If you are having this problem right now or would like to anticipate, should it happen to you in the future, read on.
In this article:
- Reasons why my air conditioner does not turn on?
- Air conditioner beeps but does not turn on
- Air conditioner does not turn on or freezing at night
- Air conditioner not turning on after winter
- How to troubleshoot air conditioner not turning on
- How do I reset my air conditioning unit?
- Other common air conditioner problems
- How long does an AC fuse last?
- How to turn on split type AC without remote control
Reasons why my air conditioner does not turn on?
Experts and air con care centers would say that the AC not turning on is fairly common, especially if it takes on a lot of load every day. So, to at least pacify that feeling of panic, here are the nine most common reasons why your air conditioner does not turn on.
1. Tripped circuit breaker
Your main fuse is most likely unable to take on the load of the AC, so they are commonly installed with a separate circuit breaker. If by some chance your air con does not have a separate one, your circuit breaker will become overloaded, causing the circuit breaker to trip because of too many appliances in use. When it is tripped, you cannot turn on your AC.
2. Blown fuse
The main fuse can also be blown up for a variety of reasons. Faulty or old wirings could be one problem and a short circuit from a previous storm could be another.
The point is, you must make the continuity test for the fuse to know if it is working. Make sure that the two ends of the fuse beep with the multimeter. If one does not, you need fuse replacement to turn on the AC.
3. Clogged AC filter
Another common reason is having a dirty air filter for the aircon. This is one of the most basic maintenance tips for ACs, yet it is hardly recognized. When it is clogged, it is not just the airflow that is obstructed because the water droplets that the condensation tray collects would fall in the coils, become frozen because they cannot get out and block the coils with ice.
4. Clogged evaporator coils
It might not just be the air filter that is dirty. Like the previous one, debris and dust buildup in the evaporator coils could lead to ice formation and obstructed airflow. In the long run, without regular AC maintenance, it could lead to AC breakdown, hence, you not being able to turn it on.
5. Dirty condenser lines
The condenser lines are more spacious and without regular checking, you would not know that a bird, rodent, and debris buildup might again be the cause of your AC not turning on. You can clean this DIY by lifting the lid off the condenser lines. Suck out obstructions using a vacuum. But if it is too complicated to clean, call your AC care center.
The refrigerant refers to the ACs coolant or freon. Sometimes, it takes years before a freon should be added but when it has leaks, the AC would not work as it should. One of its consequences in the long run would be not turning on.
Leave this one to the hands of an HVAC professional. DIYing it might lead to another problem called refrigerant poisoning.
7. AC motor has stopped working
Once you hear those loud, whirring sounds out of your AC, it is time to have it tested before it stops turning on. A capacitor test would be required for this as it could give the specific amount of motor power left in your AC.
If this seems to be the issue, get a quotation first. Sometimes, replacement could be more inexpensive than the repair costs.
8. Home’s wiring issue
Sometimes, it is not the AC that is the problem. Sometimes, it could be about issues on faulty wiring in the home. Early signs of having a wiring issue would be flicking lights once you turn them and noisy appliances once you turn them on. If unmitigated, expect appliances like the AC to not turn on.
9. Damaged thermostat
This one is one of the most important parts of an AC because it is the main control panel of the unit. If it is busted, broken, or it might be in need of replacement, the AC would never turn on. Start by checking the thermostat. Go through the manual again to DIY fix this.
10. Short cycling
When the system constantly turns on and off intermittently in the duration of use and never lets on a full cycle yet never rests, it wears off. When this happens, the AC might eventually stop turning on. Have this treated by professionals only because it includes more delicate parts of the AC.
If you found out that one of these are the reasons behind your AC not turning on, then at least you already have a head start of what to do and who to call. But if for some reason these reasons do not fix the issue or reveal the problem, you might as well carry your AC for a comprehensive check and maintenance run to the AC care center and let them fix what needs to be fixed.
Air conditioner beeps but does not turn on
When the AC beeps but does not open, it could be due to a tripped circuit breaker or a blown fuse. If both are okay, start checking for a beeping sound when you continuously flip on and off the breaker or fuse. If the beeping sound is not eliminated, you have a faulty motor or sensor in the AC system.
Air conditioner does not turn on or freezing at night
If your AC particularly does not turn on at nights and find that it has an ice buildup around it in the morning, here are the most common reasons that you should look for:
- Insufficient air flow due to clogged filters, coils, and condensers.
- Low levels of refrigerant or freon. Adding refrigerants during summer should be done twice during the season.
- Air temperature is not regulated. Note that once the AC reaches its best temperature, it would evenly cool the room all night. When you lower or raise it intermittently, it would shut down at night time in the long run.
- The blower motor is faulty and needs replacement.
- A stuck contractor. The contractor is this very small external part of the AC system. It allows the outdoor unit to continue running to prevent ice buildup. So, of course, when it is stuck, it does not do its job, allowing for overnight freezing and eventually shutting off in the middle of the night.
Air conditioner not turning on after winter
ACs can sometimes go into hibernation too. When it stops turning on after winter, it could be very frustrating. So, to amend that, you must know these three common reasons behind an AC not turning on after winter.
- Rule out the most common problems: Before getting too complicated with this, you must carry out a first aid check. For this, you need to check these three: emergency shutoff, the filter is clogged, and a blown fuse or a tripped circuit breaker. If it is because of these three, the main problem was electrical.
- Faulty AC fans: This means that your air handler, specifically, the AC’s blowers are not working. You can find these in the basement. When they are particularly old, they tend to back down during the winter. This is mostly signified by silence from the vents or blow motors and the crazy part is you could just assess them when spring comes.
- Condenser issues: Ice buildup in the condenser can cause a compressor overheating and can cause malfunctioning. Worse, it could lead to the AC not turning on at all. For this to be mediated, you have to examine the coils by opening the exterior panels of the AC system.
Related: Do Vent Filters Work?
How to troubleshoot air conditioner not turning on
To make sure that you could have a handy solution to your AC problems, we have listed here some AC issues with their corresponding troubleshooting mechanism.
|Thermostat adjustment||Thermostat calibration; HVAC professional check|
|Dirt, leaks, and clogging||Inspection of air ducts, condensers, and filters; professional inspection|
|Drainage issues||Check for leaks and drain lines|
|Noisy AC||Replacement of AC motors and faulty belts|
|Frozen evaporator coil||Insulating air ducts; professional inspection|
|Refrigerant levels||Never DIY; have a professional come over to add freon to the AC|
|Airflow issues||Filters need to be checked every month and should be replaced every 12-16 months; professional inspection|
|Electrical flow issues||Check the electrical system that powers the AC system. This is composed of the blower motor, compressor, and the condenser fan motor.|
|Sensor problems||This is caused by sensor dislocation or forced out of position. To troubleshoot, reposition the evaporator coils. Make sure that they are not touching each other.|
|Drainage problems||When mildew and molds niche on the AC system because of drainage problems, it is because of a dirty drainpipe. Have someone inspect and clean it thoroughly.|
|Outdoor fan not working||This should be a cause of panic. It means that you have a faulty compressor. Have it checked in the AC care center.|
|Thermostat issues||Indoor AC cleaning, position of the AC should not be directly exposed to the sunlight|
|Capacitors||These are the small motors that power up the fans and the compressor. Replace immediately if it burns out. Check with a professional for replacement.|
How do I reset my air conditioning unit?
Resetting the AC just takes four easy steps. You can do it in just under a minute. To reset your AC, here is what you should do:
- Shut off the AC: Check your AC’s manual to locate the thermostat on/off button. Plug off the cord too before working on the AC.
- Get to the circuit breaker: Access the circuit breaker and find the one that is connected to the AC system. Now flip off the line connected to the AC and wait for at least 30 seconds before you power it up.
- Check if it is working: Now, go to the thermostat and power the AC on. Set the thermostat into your desired temperature and wait for it to cool properly to confirm that it is working. Monitor for at least 30 minutes. If no problems arise in between that interval, you have successfully reset your AC unit.
Other common air conditioner problems
As if not being able to be turned on is not a major issue, here are other common air conditioner problems that you should be aware of.
- AC does not cool evenly: This one most of the time depends on the amount of sun around the home it is installed in. The most common intervention for this would be installing dampers in the AC’s air duct system to manage the temperature from the AC. Sometimes, it is because the AC does not have the right size and power to evenly cool the room.
- AC does not cool at all: This is also a multi-factored issue when it comes to ACs. The most common culprit would be leaking refrigerant. Another reason is a faulty thermostat. Since refrigerants cannot be taken on using bare hands, you have to contact an AC care center.
- AC condenser turns on and off repeatedly: When the pressure drops down at a critical level, the condenser turns off the system automatically. If the condenser suddenly has an erratic on and off cycle, it might be due to short cycling. But if it produces other peculiar sounds after, it is time to visit an HVAC contractor and assess the problem.
- ACs water is leaking inside: When water puddles accumulate by the condenser during hot and humid days, leaking can be normal. If it is turned off and the water starts leaking, it is because of a clogged filter. But in other circumstances, it could be a serious issue and you might need a visit by the care center.
- AC would not stop running: This condition is primarily due to three reasons. One is due to a stuck fan relay. Second, the thermostat needs replacement and three, the thermostat cable is tripped.
How long does an AC fuse last?
We have covered here that most often than not; an AC does not turn on and other AC issues could be associated with a blown fuse. If you feel like it might have been too soon, know that fuses last long (up to 20 years).
You also have to note that AC fuses work on ‘time delays’. They turn on when you flip them on and shut off automatically once they are off. They do not wear easily so you really just have a faulty fuse if it does not last long.
How to turn on split type AC without remote control
Split type ACs have rapidly taken over the market. These remote-control dependent AC models could cause a panic once the remote bugs off. To turn it on without needing a remote, here are four things that you can do:
- Turn it on through the indoor unit: This is mostly unknown to split type AC owners but once you flip the glossy cladding of the air filter plate, you would find the on/off button there. Just press it for now while you fix the remote.
- Turn it on through a smart app: Newer models of split type ACs can now be connected through WiFi, hence, you can turn it on and off with just a tap with its designated smart application in your phone. You would not even need a remote anymore for this.
- Turn it on through the circuit breaker: Emergency on and off is one of the major functions of a circuit breaker apart from managing the electrical load of the home. When you cannot find the remote immediately, go to your circuit breaker and flip it up and down to manually turn on and off the AC.
For the untrained homeowner, an AC not turning on is ultimately a source of concern. But with what we have covered here, you do not need to go to the AC care center right away because you can assess the problem with some handy tips.
The trick here is to be knowledgeable about the different parts of the AC system and where they are located for you to check as many parts as you can. Ultimately, repair and replacement would cost a lot. So, for you not to go down that route, you need to carry on to its regular maintenance checks.