WE ARE OPEN! All filters are made in the USA in our Alabama warehouse.

How to Fix Your Air Conditioning

Why is it so hard to get an AC technician to your house? It seems like AC repair companies actively TRY to make us wait on their schedule. It’s not fair, and I’m fed up.

I guess I’m not the only one. Filter King thinks it’s SO unfair, that they’ve given me the go-ahead to publish an AC repair guide, so our customers can save time and money by fixing their air conditioning themselves. It’s time to fight the system and secure freedom from expensive repairs that take days to complete. VIVA LA REVOLUTION!

Hold, comrades! Before we topple the oppressive air conditioning tyrants, we do have to clear one thing up. AC professionals exist for a reason. Working on your own AC system can be very dangerous. If you don’t feel comfortable working with electricity, mechanical parts, or refrigerant, you may want to sideline yourself for this particular revolution.

That said, let’s create a plan of attack:

1.) Find out what tools are needed to work on an AC system

2.) Diagnose common problems with AC systems

3.) Use our tools to fix those problems

We ride at dawn. Let’s get started.

What tools do I need to work on my air conditioning system?

In order to dismantle the systematic subjugation of our people (homeowners on a budget), we’re going to need the proper tools. There are some things on our list that you likely already own, and a few that you’ll probably need to buy. I know, the whole point of this is to spend less money, but all of these tools should round out to less than $50, and even one successful repair with them will save you hundreds. Besides, everyone must make sacrifices for the good of the revolution.

Here’s a quick list of the tools and materials you’ll need:

1.) Wrenches – either a comprehensive set or a single adjustable wrench.

2.) Multimeter – a handheld Game Boy type thing that gives you values of current, voltage, and resistance

3.) Screwdriver – we prefer ones with interchangeable heads. Also, make sure it’s insulated.

4.) Socket wrench – the thing that does that really satisfying clicking sound as you move it back and forth

5.) Pliers – needle nose.

Depending on the fix you need, you may need to purchase parts or materials. This will be covered in more detail in future guides.

How do I diagnose the problems with my AC?

Our intelligence officers have discovered the secret plans that the Official State of Professional HVAC Technicians have kept hidden from the people for decades. These documents reveal the clandestine methods of AC repair units that we can now use to our advantage. Here’s an executive summary that we will be handing out to all of our revolutionaries.

To properly diagnose your AC problem, you have to know roughly how it works and which parts break down most often.

Modern AC systems consist of two main parts. There’s a cooling unit, which rests outside your house. Then, there’s a kind of “distribution center”, usually in your attic, that takes the cold air from the cooling unit and moves it around your house.

Using this very basic framework, we can start to point to issues. If your AC system is blowing air, but it’s not cold, it’s a problem with your cooling unit. If cool air is dripping out of the vents, but there’s no force behind it, there’s a problem with your venting system.

The most common problems for your AC unit are as follows: dirty condenser coils, a broken start/run capacitor, and a broken contactor. We’ll break each of these down and walk you through the solutions.

The first step to any AC repair is to turn off all of the electricity in your house. Yes, all of it. “But I’ll have to reset all my clocks!” Steady yourself, comrade - inconvenience is preferable to death.

Ok, all joking aside for a second: You really do need to turn off your power. One slip up-and you could be electrocuted and killed. AC repair is dangerous. Make sure you REALLY know what you’re doing before you start. Alright, back to it.

Dirty Condenser Coils

This is one of the most common causes for an AC breakdown. All you need to do to solve it is clean your condenser coils. Don’t worry, it’s not as hard as it sounds.

Take a hose with a spray nozzle attached. Go to your cooling unit (the big, loud, cube-shaped thing outside your house). Point the hose upward at the side of your unit and spray all the way around the top perimeter. You should see a bunch of gunk and dust being flushed out. Let it dry in the sun, and you’re all set. If that was your only problem, your AC should kick back on soon. If not, we’ll have to go deeper.

Replace Your Start/Run Capacitor

Heads up, this is where things get really dangerous. Turn back now if you don’t want to risk a severe injury or death.

Your start/run capacitor is a critical component that fails fairly often. We need to inspect it and, if necessary, replace it.

First, turn your power off. On your outside cooling unit, you’ll see a panel with some screws holding it in place. Make sure your power is OFF. Unscrew those screws and remove the panel. By the way, make sure your power is turned off. From there, you can inspect the capacitor. Move some wires around with an insulated screwdriver. See if any are chewed up, broken, melted, or rusted out. Take a photo of the entire arrangement before continuing work. This will help you put everything back where it needs to be when we’re done. If you see any malfunctioning wires, they’ll need to be replaced. Now, on to the capacitor itself.

Your start/run capacitor is what helps your system turn off and on several times a day without burning motors and causing damage to itself. It looks like a big cylinder with some wires coming out of the top. If yours looks old, rusty, and pathetic, you should probably replace it.

Even though it may not be the direct cause of your outage, an old capacitor cannot do its job of preventing damage well enough. This means that replacing it will reduce the likelihood of future outages.

Before taking out the capacitor, you have to discharge it. Not to sound repetitive, but you REALLY need to make sure your power is off for this part. On the top of the capacitor, you should see three terminals labeled H, C, and F. Take your insulated screwdriver and touch it along both the H and C terminals for a few seconds. Then, do the same with H and F. The goal here is to create short circuits between the terminals, which releases the stored energy in the capacitor safely. WEAR GLOVES AND DO NOT TOUCH THE METAL OF THE SCREWDRIVER WHEN YOU DO THIS. If you do, your internal organs will suddenly become a very hot vapor and quickly escape through your various orifices.

Some capacitors only have two terminals. To discharge this, just do the same as above with only those two terminals.

Once you’ve discharged it, you can remove it, take it to the hardware store or look online, and get a new one of the same brand and model. Replace it by screwing it back into the system, replacing any wires removed during the process, and then securing the new capacitor to the system with its bracket.

Replace Your Contactor

Near the capacitor, you’ll see a complicated, roughly cubic thing with wires coming out of it. That’s your contactor. It goes wrong a lot, and it’s about $25 for a brand-spanking-new one.

Make sure your power is off. Remove the wires on the old contactor. Unscrew the contactor from the unit. Throw it aside, it’s garbage now.

Take your new contactor, screw it into the system, and replace the wires. Boom, new contactor. Easy peasy.

Next Steps

If none of those repairs fixed your AC, fear not! We will be publishing more guides in the near future that cover issues that are less common. Be sure to check back with Filter King each week for more guides.

If these quick fixes did resolve your issues: Huzzah! The revolution was a success. Relish in the defeat of the tyrants! The work, however, is just beginning. With our new-found freedom from expensive repairs, we must ensure the longevity and sustainability of our way of life.

AC system maintenance is key to this. The number one thing you should commit to going forward is replacing your air filters AT LEAST every three months. This is what keeps your system, breathing well, and it can drastically reduce the likelihood of needing another “revolution”.

Filter King’s online store has any size of air filter you need. Just find your size, order it, and it’ll be at your house in a few days.


We’ve had some light-hearted fun in this article, mostly at the expense of HVAC professionals. But in all seriousness, we recommend hiring a professional to do almost all AC repairs. They are vastly qualified, and even though you may have to wait, they’ll get the job done safely and correctly.

Working on your own AC is dangerous. Let a professional take that risk, so you can live to fight another day.