Can I Install Central Air Myself? (Find Out Now!)

Central air is one of the most essential components of a clean and comfortable home. While it’s still viewed as a commodity, installing a central air conditioning system in new homes is pretty standard. However, if you have an older home and want to install one, this can prove to be difficult on your own.

It’s possible to install a central air yourself, but it’s challenging without the proper tools, training, and experience. Central air involves many different components such as ductwork, an indoor coil, and an outdoor condenser. A combination of physical labor and precise science goes into installing central air.

Unless you have previous air conditioning or HVAC experience, I would highly recommend attempting to install your central air. If, however, you’re hard-working and innovative and want to save money, this article will explain how to install central air.

The first thing you’ll need to do is pick a good spot outside your home for your air conditioner. Ideally, you want a flat area close to the house where there aren’t a lot of trees or shrubs. Debris and branches can get into the air conditioner and damage it.

Once you’ve picked the right spot, you’ll need to lay an air conditioning slab or pad on the ground. The AC will then sit on top of this, so you must find a sturdy, flat area to set your pad. Make sure that you pack the dirt down beneath the pad because the weight of the air conditioner could cause the ground to shift beneath the pad.

Inside your home, you’ll have to install an A-coil on top of your furnace. Many people don’t realize that there are indoor and outdoor components with central air. There are then several refrigeration lines or pipes that connect the two sections. Installing the coil on top of the furnace is pretty tricky, so brace yourself.

You’ll have a section of metal ductwork known as a plenum that’s connected to the top of the furnace. The goal is to insert the coil neatly in between the metal plenum and the furnace. To do that, you’ll need to cut the section of metal out of the way, matching the exact dimensions of the coil. It’s a good idea to get a coil that’s the same width and depth as your furnace and plenum so that the coil fits neatly in between both.

With your liquid and suction lines running from the air conditioner to the coil, it’s time to braze them together to form an airtight seal. You need to braze instead of crimp or solder the lines because of the amount of pressure inside of them. A solder or crimp joint isn’t strong enough to withstand the pressure, and you’ll have to use brazing material.

Brazing is very similar to welding, and if you know how to weld or solder, you likely know how to braze. Don’t try to braze your central air if you don’t have any previous experience. Brazing involves the use of oxygen and acetylene, which produces incredible heat. They’re a fire and explosion hazard if you don’t know what you’re doing.

At any rate, either you or a helper will need to braze the joints together to continue.

Once your liquid and suction line joints are brazed to both the air conditioner and the coil, you’ll want to conduct an air test. Air tests are done to ensure that your braze is airtight and that there isn’t a leak anywhere. For inexperienced brazers, there’s almost always at least one leak when you braze.

You’ll need air conditioning gauges and a nitrogen tank to perform the air test. Connect one end of the hose to the nitrogen tank and the other end to one of the air conditioners’ ports near the liquid and suction line. Blow nitrogen into the air conditioning lines and check your gauge to ensure there aren’t any leaks. There’s enough pressure in the lines from the nitrogen that you can usually hear air hissing if there’s a leak.

If the air test checks out, it’s time to vacuum or pump down the system. To do this, you’ll need a vacuum pump and your air conditioning hoses, as well as a micron gauge. This is another part that’s extremely difficult to do without experience, and I would recommend against it.

The goal is to get your micron reading below 400 and keep it there. If the number sits at 400 or less but starts shooting up into the thousands, there’s a good chance that you have a leak somewhere in the system. This means that you’ll have to start over with your air test and brazing procedures until the leak is found and fixed.

In order for your air conditioner to operate, you will have a low-voltage thermostat wire running from the air conditioner to the furnace. You’ll also have an electrical wire running from the air conditioner to your main breaker panel. Make sure that you consult the ID labels on your air conditioner to ensure that your wires are the right size and that you connect them to the right places. Incorrect connections will lead to mechanical failure, and your air conditioner won’t start.

Additionally, it’s always advisable that you install a disconnect switch between your air conditioner and your panel box. Essentially, you’ll have an electrical wire running from the panel box to the disconnect, which should be attached to the outside wall next to the air conditioner. You’ll then have a second electrical wire running from the disconnect to the air conditioner. The disconnect acts as an emergency shut-off and a service shut-off.

Related Questions

Is it wise to install my own central AC?

No, in the long run, and the short run, it isn’t a good idea to install your own central AC. There’s about a 0% chance that you’ll do everything correctly without the proper training and tools. An improperly installed air conditioner will last only a fraction as long as a professionally installed one.

How long should a central AC last?

The average lifespan of a quality air conditioner is anywhere from 15 to 30 years. Cheaper and lower-quality central ACs will only last 8 to 15 years, but they can last much longer with proper care and maintenance. An improperly installed air conditioner can give out as early as three months to several years.