How Long Does it Take to Install an AC Unit? (DIY Vs Contractor)

The first question most people who are buying a new air conditioner ask is: how long does it take to install an AC unit?

Well, do not let the excitement get the best of you, as installation timelines vary from AC to AC. To be on top of the process, you need to know the factors affecting the installation time.

So, keep reading on as this guide will answer all your questions regarding how long to install an air conditioner.

Factors That Affect Air Conditioner’s Installation Time

Here are the six main factors that affect an air conditioner’s installation time:

AC Unit Type

When it comes to HVAC units, there is more than one type. The type you chose will influence the installation duration.

For example, the installation time of a window AC will be less than that of a central air conditioner, i.e., if the complete system has to be installed.

KeepRite Air Conditioner
Installation Type

With any AC type, there are two installation procedures:

Simple AC System Change Out

A system change out is a lot simple, and the installation time is shorter than a complete system installation.

A system change out happens if you have the necessary equipment in place from the old unit to install the new one.

This will not just save time; it will also save substantial miscellaneous costs.

Full HVAC Installation

Replacing ductwork or installing an HVAC system from scratch takes longer than any other type of installations.

This is because your technician would most likely have to rewire the thermostat or replace the ductwork. If other issues come along the way, it will take even longer.

Daikin Thermostat

Size Of Your Home

This factor is quite significant when determining the length of time it will take to install your AC unit. As expected, the bigger your home, the longer it will take to install the HVAC system. The reason for this is that larger homes require more extensive or even multiple units. Learn more about sizing an AC here.

Location of the Unit

If you live in a building with a high roof – such as a condo – the installation time will increase. Buildings with high roofs require cranes to lift the AC unit to the rooftop.

Sometimes, HVAC companies hire extra personnel for installations like these so that it does not take more time than required, but it is important to account for it either way.

Timeline for Installing Different AC Types

As mentioned above, the type of AC you choose influences the amount of time it takes to install. Therefore, let’s take a look at the different AC types and the time it takes to install them:

Central AC Units

How long does it take to install a central AC? The answer to this is a little more complicated as external factors come into play when installing a central AC unit.

It usually takes between 3 to 5 days because installing it from scratch or completely replacing it would involve rewiring thermostats and replacing ductwork.

On average, it will take three days, as one day is dedicated to the changeout and two days are dedicated towards ductwork replacement.

If the ductwork is more extensive, it could even take three to four days on its own. Due to the amount of work that goes into installing central AC units, their installation cost is the highest.

Mini-Split AC Units

Mini-split AC units come in two types, ducted and ductless. The one you choose affects the timeline of the installation.

  • Ductless Units:
    These are more common and take less time on average, as a mini-split AC unit can be installed in approximately 4 hours or a day or two if there are multi-room systems that are more complex.
  • Ceiling Or Ducted Units:
    These take a lot more time — at least a day, or even more, depending on where the unit will go. If it is located on the roof, tin sheets or tiles may have to be removed so that the indoor fan coil fits inside.

Building with Several Mini Split AC Units
Window AC Units

An experienced HVAC company can install your window AC unit in less than a day if it is a big one, whereas a small window AC can be installed in minutes!

The steps are usually relatively straightforward, so it does not take a long time to install. The length of time a window AC takes to be installed depends on its size and type.

Furthermore, you should keep in mind that a through-the-wall unit will take longer to install.

Portable AC Units

There is no longer a need to keep Googling: “how long to install a portable air conditioner,” as we have the answer!

Portable air conditioning units are probably the easiest and most hassle-free to install. If you have all the necessary components, you could even install it in just ten minutes, or a maximum of thirty.

Since they are small in size and do not have to be permanently installed, their installation cost is the lowest. See more on the types of portable ACs here.

Related Article Portable AC Venting Options

Can You Install AC Units DIY?

The simple answer to this is: yes! But, should you? Here are some of the pros and cons of installing an AC unit all by yourself:

Lower costs:

The AC unit itself may be pricey, but choosing to install it yourself can help you save on installation costs.

However, it will probably take you longer to complete the job compared to professionals, so you should consider that before going all in!

Learning A Useful Skill

Doing it yourself may quench your thirst for knowledge! Those who have always been curious about the process can properly delve into it while learning how to maintain it. You will be improving your technical skills and making yourself more independent.

Get What You Want

If you want more control over the process of buying and installing an AC, DIY is the way to go. Most AC companies recommend specific types of units or brands, so if they do not have the one you want, you can buy one from elsewhere and install it yourself.

Getting A Permit

If you are inexperienced with HVAC or electrical work in general, you may find it challenging to understand the permit system — a prerequisite to installing an AC unit.

It varies from area to area, as sometimes you may need permits not just for the units but also the platforms or housings for the AC unit.

Before getting started, you will have to talk to city or county officials in your region to understand the process better.

The Time It Will Take To Install

Installing an AC unit is not usually a one-person job, especially if this person has never done it before. Navigating the process takes time and patience, as you have to figure out how to do it all by yourself.

Why Should Professionals Install Your AC Units?

If you want to leave your AC unit installation to experts, here are some pros and cons to consider before doing so:

Architect with Building Plan

Here are a few advantages of hiring professionals to install your ac units:

No Need For Physical Labor

Installing an AC unit all by yourself can prove to be an uphill task. You may be required to perform necessary physical tasks, such as:

  • Lift heavy parts
  • Prepare the installation sites
  • Crawl under your home
  • Climb on the roof
  • Pour concrete

All you will need to do with a professional is sign off on the work, pay them, sit back, and relax.

Won’t Have To Worry About Paperwork

Aside from the physical labor required, most homeowners hire professionals also to take care of the paperwork.

The HVAC professionals or contractors you hire can get the permits you need, making it easier and quicker to get things done.

Maintenance Plans

Most of the time, professionals include maintenance plans along with the installation packages you choose.

They will be familiar with the system already, so they can come back when you need them to and allow your system to run safely and healthily.


There are some cons to hiring contractors to install the AC for you.

Increased Cost

Paying labor costs for AC installation by professionals is one of the biggest cons as it does cost a significant amount depending on the work, but it will mean your AC unit will take less time to be functional.

Finding A Trustworthy Company

There may be too many or too few options when considering which contractor to hire when installing a new system.

Most contractors function in certain areas and clients in a specific region. If you’re not in that region, you may have to keep looking for one who will work for you.

View our top recommendations on central air conditioners here.

People Also Ask (FAQ)

Is It Hard To Install An AC Unit In The House If You’re Inexperienced?

Anything is difficult to do if you’re inexperienced, and installing an AC unit is no different. However, some variants can be easier to install than others (Installing a window unit would be straightforward compared to installing a central AC). In any case, you will need to do your homework before beginning.

How Much Is A New AC For A 3000 Square Foot Home?

It is estimated that you would need at least a 5 ton AC for a 3000 square feet home, which amounts to around $2900-$3500. If you are looking for a central AC unit, that will cost anywhere Between $7000-$12,000.

How Long Do Air Conditioner Units Typically Last?

Older models of ACs lasted approximately ten to twelve years. Modern ACs have a lifespan of about fifteen to twenty years. How long your air conditioner lasts will depend on how well you maintain it. Find out more on this topic of AC lifespans here.

Should I Replace My 20-Year Old Air Conditioner If It’s Still Working?

If your air conditioner is still working, there is no reason to replace it. Even if it is 20 years old, it is unnecessary to contemplate replacing it until it starts showing signs of slowing down.

What Is The Best Month To Buy An Air Conditioner?

Buying an air conditioner during the off-season is the best choice, and the time between winter and summer (spring and fall) are considered the off-seasons in this industry. You will find the cheapest deals during this time.


It is essential to consider all your options fully so that you can make an informed decision. When it comes to installing a new AC unit, there are many factors to consider, and you need to choose an option that saves you money, time, and ensures zero damage to your new system.

And if you plan to DIY it, make sure you watch a couple of YouTube tutorials before even picking up a screwdriver!

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.