If something goes wrong with your window air conditioner, you’ll want to know where the fuse is located. The fuse is responsible for protecting the electronic control of the device. Your AC unit must be unplugged if its power supply is insufficient. Then, unscrew the cabinet’s lid to reveal the device. Using a multimeter can help you determine if a fuse has blown on your circuit board. When it comes to air conditioner fuses, there are many more things that you need to know about them. The most crucial thing to know is how to locate the fuse in your air conditioner. Let’s get started right away!
Why Do Air Conditioners Break on Hot Days?
“It’s a hundred degrees outside, and the A/C stopped working. Is it possible that the air conditioner knows when we need it most and breaks down? In my 23-plus years in the HVAC industry, I’ve heard this many times, and it’s humorous because it’s accurate. Your A/C is more likely to fail on the warmest days of the year, even though it doesn’t have the ability to “know.”
Almost any electrical appliance falls into this category. A/Cs, in particular, are particularly vulnerable to the damaging effects of heat. Temperatures rise, causing electrical components to overheat, resulting in their failure. It is the capacitor and fuses that are most susceptible to overheating when it comes to air conditioning.
As a result of the lack of airflow, these components have a higher likelihood of malfunctioning. They may blow, but the probabilities are better if it’s hot outside. The fuses will be the center of our attention here, as will the ease with which they can be replaced. Here are specific, step-by-step directions for resolving the issue:
- The fuses are being checked.
- Performing a voltage check.
- Taking out and replacing the fuses.
Bring that A/C back to life without spending a fortune.
What Do Fuses Do?
Consider a fuse to be a top-secret agent. The shot is taken. An air conditioner’s fuse will blow in the event that it receives more amps than it can handle. As a result, the fuse can only tolerate a limited amount of amperage, dependent on the A/maximum C’s rating. It is more likely to blow if the fuse is too small, but if the fuse is too large, it could enable more than the rated amount of current to reach the unit and cause fatal damage. Your breakers are no different. That’s quite cool, isn’t it?
More About The Air Conditioner Fuse
When it’s hot outside, your air conditioner has to work harder to keep your home at a comfortable temperature. When you use the device for long periods of time, it may even overwork itself. A tripped breaker or blown AC fuse can occur in this situation. In order to avoid further damage, the system does this action. However, this is merely an attempt to safeguard the system in the event of a problem. Temperature-sensitive: The fuse filament will melt if there are any power spikes or if the unit becomes too hot. Only a fixed amperes load can be supported by fuses. As a result, if the voltage is too high, the fuse will explode. A blown fuse means that power will be switched off to the unit, preventing additional harm.
How to Check if Your A/C Fuses Are Blown
When the A/C unit outside isn’t working, you’ll know something is wrong with the fuses. Only a faint humming may be detected. A voltmeter is the most accurate instrument for determining whether or not a fuse has blown. For those of you who do not have a voltmeter or are uncomfortable evaluating voltage, I will provide an alternative method for checking fuses once we complete this one.
Warning! In this area, you’ll be dealing with live power. With the power off or the fuses gone, it is impossible to test fuses and voltage. If you are not a trained electrician, you should avoid working with live electricity. Even if we are only taking a voltage reading in this instance, we must proceed with caution and self-assurance.
- Disconnect the power source. The exterior condenser of your A/C system has a gray box mounted on it, which is what you see most often. What it looks like is seen in the photographs below.
- Disconnect the wires by removing the plug. Open the lid by lifting or swinging it open. Some doors require a modest amount of pressure on a small tab before they may be opened.
- The disconnect’s wire should be exposed. In order to protect the wire, there should be a second cover inside the disconnect (or protecting you, depending on how you look at it). A single screw may be all that is holding this in place.
Note: Fuse compartments are not always found in disconnects. Despite the fact that it is the norm, and even the law in many states, some people do not. Because of this, they would not be your concern.
How to Test the Voltage on an Air Conditioner
- You should be able to locate the incoming and outgoing cables after the wiring is exposed. Incoming power is called the “line,” and exiting power is called the “load” (the outgoing power). Your light switch or receptacle (which uses 110/120 volts) isn’t like this, so pay attention: Neither of the two lines is a 110 volt source, yet both of them are.
- Determine that the voltage (V) setting on your meter is at “0 volts” before proceeding (or infinity).
- On the “line” side of the circuit or fuses, the positive (+) and negative (-) leads must be connected to the respective lugs of the circuit. If you have a red meter, the red wire should be connected to your lug for the black “line” wire, and vice versa for black.
- Your voltage meter should now read between 220 and 240 volts, with a margin of error. In this range, you have validated that the disconnect to your fuses is receiving electricity. The fuses are not the issue if there is no reading, but if resetting the breaker doesn’t work, you may need to consult an electrician because the issue is most likely at the breaker panel.
- If you were able to see voltage during step #4, then proceed to step 5. You’re hoping for a voltage of between 220 and 240 volts. When you see this, you know that the electricity has made it to the fuses (like it should). It’s time to replace your fuses if you see voltage on the line side but not the load side.
Steps To Find The Fuse In A Window Air Conditioner
Even if you know where to look for the window air conditioner’s fuse, performing a self-fuse check can be hazardous.
The best thing to do if you don’t know what to do is call an HVAC company in your neighborhood to inspect your air conditioner. Using a voltmeter, on the other hand, is preferable if you want to do it yourself. In a window air conditioner, where is the fuse? Step-by-step instructions are provided below.
Step #1. Locating its disconnect box
The first step in determining if a fuse has blown is to determine where the fuse is placed. In most cases, it is a dark grey hue and is attached to or near the outside unit itself.
Step #2. Locate the cables
Open the disconnect box by swinging or lifting both the inner and outer covers. The cables that are hidden within will be visible if you do this. Outgoing load and inbound line wires must be found. Due to the fact that both wires contain 110 volts, extreme care should be taken.
Step #3. Check your voltmeter
The voltmeter must first be checked to see if it is working properly. A reading of 0 volts should be shown. Infinite numbers can be seen on some models.
Step #4. Test the wires
Step 2: Connect the voltmeter leads to the lugs that connect the wires. The voltmeter’s measurement must fall within the range of 220 to 240 volts. Fuses provide power, as evidenced by here. Nonetheless, if the voltmeter shows nothing, the fuse is not the problem.
What If You Does Not Have A Voltmeter?
However, not everyone has a voltmeter at their disposal. Even though the fuse may have blown, don’t worry since you may still check to see whether or not it has. The disconnect box can be used to check its volt capacity directly. Replace the old one with a new one of equal or greater capacity. The fuse has blown if the air conditioner is already running.
How to Remove Fuses
- You should check your fuses to make sure they aren’t exposed in the same place as your wire. The “T” handle of many disconnects has fuses built in, therefore you’ll need to remove the handle to access the fuses.
- In any case, you’ll need to pull out the handle to stop the fuses from tripping while you operate. The disconnect and fuses on the line side will still be able to receive power. To guarantee optimum safety, you should return to your air conditioner and turn off the breaker.
- It’s now possible to remove the fuses by either popping them out with your hands if they’re in the handle itself, or grabbing them with a set of insulated pliers. When working with electricity, never use bare metal handles.
This may seem like a lot of work, but it’s actually rather simple. Before you perspire to death, simply replace the fuses with their original locations.
Air Conditioner Breakers
If you have a 25–50 amp circuit breaker in your home, your air conditioner is likely to be plugged into it. This is a 208/230 volt two-pole breaker with two switches.
What Kind of Fuse Does A/C Use?
Buying the correct fuses for your air conditioning system is critical. Even if you’re desperate, never use a fuse that’s rated for more amps than you actually require. If you allow your condenser to get too many amps, it can malfunction and could be fatal to the device. In the worst case scenario, your air conditioner will be overprotected as a result of the smaller fuses blowing. Meaning the problem will return sooner rather than later.
The size and type of the fuse (usually a “TR” type) are frequently printed directly on the fuse. It should be possible to retrieve the air conditioner’s amp rating from its rating plate if it isn’t. These can be found within the air conditioner’s access panel. Finding it should be a breeze. It’s possible to get your A/C unit running temporarily with a 20 amp fuse if you can’t locate any amp rating on the fuse or rating plate, so you might try that first. (Don’t exceed the breaker’s amperage capacity.)
As long as it doesn’t blow as soon as you turn it on, you’ll be fine. A short in the wiring may be to blame, and you should contact an electrician or a heating and air conditioning professional to find out what’s going on. Turn the thermostat all the way to “off” and turn the A/C off. A fuse reducer is also necessary if the old fuses are larger in size than the new fuses (we’re talking about physical size here, not amperage).
These will bridge the gap between your larger and smaller fuses by attaching to the ends of each. You should never use a disconnect to get around the fuse. This is not only a good method to wreck havoc on your machine, but it also puts you and your family in danger. It is a TERRIBLE idea to try and get the A/C to operate by inserting copper tubing or aluminum wire where the fuse is located. (It’s true, people do this, and it never works out well.)
Why Does My Air Conditioner Keep Blowing Fuses?
Take a closer look at your A/C unit’s fuses and breakers to see why they’re tripping or blowing. When your A/C blows a fuse, it’s letting you know there’s a problem. There may be a more serious issue with your cooling system if the fuse continues tripping over and over again. There could be a number of reasons for this:
- Circuit, fuse box, or power supply issues are at the root of this. When there is too much amperage in the line, fuses and breakers blow as well. In your desperation, you might consider getting an even bigger fuse, but it would be an exceedingly risky move.
- The condenser’s capacitor, which helps regulate electrical current, is malfunctioning.
- A filthy condenser coil (or a dirty air filter) is a recipe for catastrophe in hot weather. The machine overheats and blows a fuse because it is working so hard to force cool air through a blocked filter. The beginning of the warm season is a good time to perform a deep cleaning on your unit.
- A clogged filter or a jammed motor is to blame. To compensate for a malfunctioning component, the entire system has to work harder.
- Several wires are hanging loosely from their plugs. A sudden shift in temperature can cause problems with connections.
- It’s the condenser fan that’s broken. A blown fuse might be caused by an overheating system.
- It’s a bad compressor, that’s what it is.
- The amount of refrigerant in the system is excessive (or too low).
- It’s simply past its sell-by date.
Consider hiring a qualified HVAC technician or purchasing a new air conditioner.
Get the Air Conditioning Working Again!
I hope your air conditioning issue has been rectified. If it hasn’t, you may have a problem with your air conditioner’s power capacitor. To recap, the most common air conditioner components to fail on a hot day include your air conditioner’s fuses and capacitors. Then check out my article How to Diagnose and Repair Your Air Conditioner (A/C) Capacitor if you haven’t already. You’ll learn how to check for a blown capacitor and what to do if it is the cause of your problem. Don’t guess if your system’s results don’t match what I’ve described here. Contact an expert. My comrades, please keep your heads up. To the best of the author’s knowledge, this article is correct. Personal counsel or professional advice on areas of business, finance, law, or technology should never be relied upon in lieu of the information provided here.
What Are Leads and Lugs?
- a voltmeter’s lead wires The test is made safe by the use of insulated grips and strong metal ends.
- Disconnect lugs: The metal block-mounted screws. Wires are held in place by these screws. ‘Line’ and ‘Load’ are the correct terms.
In order to check the voltage, place the metal end of the lead on the lugs and press down on it as described in the previous paragraph.
Some Tips To Remember
Consider the following advice:
- Make sure your hands and feet are completely dry before attempting to check the fuse on your own. The floor should also be free of any debris.
- If your air conditioner’s fuse keeps blowing, you’ve got a bigger issue to deal with.
- You’ll be glad you did later on if you have a snapshot of the disconnect box to refer to. Make sure that the wires and the fuse are where they are supposed to be by using this method.
- Having a professional HVAC expert inspect your air conditioner is always recommended. They’ll be able to identify the problem and fix it straight away.
It’s A Wrap!
Your AC’s fuse has been explained in detail in this article. We’ve already discussed how to tell whether it’s blown. The location of the window air conditioner’s fuse should be familiar to you by this point. In case the fuse has truly blown, call a specialist. You may be able to accomplish it yourself if you’re knowledgeable and confident in your abilities. When doing so, be extra careful.