Can I Install A Mini Split Myself? Weigh The Pros And Cons

Many homeowners are tempted to install a mini split heating and cooling system in their homes themselves. Doing this may cost less upfront, but a DIY mini split install comes with many risks. 

While it may seem like a simple task, installing a ductless mini split system is a complex process that requires specialized knowledge.

In the end, the risks often outweigh the benefits.

As a homeowner, I know why these systems, also called ductless air conditioners, have become so popular: They provide better heat and air conditioning than forced-air HVAC, baseboard heaters, and windows ACs. 

They’re also more energy-efficient, so you spend less for better comfort.


However, ductless systems do cost a lot more to purchase and install than, say, a regular furnace and outdoor condenser for AC. That makes DIY projects very tempting.

And, thanks to my work with Pierce-Phelps, a major HVAC distributor, I know what can go wrong.

There’s a lot at stake.

I’ll start by explaining the benefits of installing your own mini split. I’ll even walk you through some of the steps. I’m sure you’ll want to understand the process, even if you go with a professional.

And, if you’d like to learn more about how a mini split can benefit your home, you can set up a free consultation with a certified installer in your area. Use our dealer locator to find an HVAC contractor with an excellent reputation in your area.


Benefits Of A Homeowner Installing a Mini Split

Here are the reasons I usually hear when homeowners want to install their mini split:

Saving Money

One of the biggest benefits of installing a mini split AC unit yourself is saving money on labor costs. Hiring a residential HVAC contractor can add up quickly, especially if you have an expansive multi-zone mini split or a dual-zone system.

Customizing It

By installing the ductless air conditioner yourself, you have more control over the placement of the indoor and outdoor units, as well as the routing of the refrigerant lines. These options allow for more customized heating and cooling.

Using Common Tools

Installing a mini split typically requires basic tools that many homeowners already have on hand. You’ll need a drill, saw, screwdrivers, and other items.

Risks If You Install A Mini Split Yourself

What could happen if you try to install the mini split yourself? Here are some of the risks: 

It Won’t Heat And Cool Properly

One of the biggest risks of installing a mini split DIY-style is that it may not function properly. Improper installation can cause the unit to run inefficiently, costing you more than it should. Even then, you won’t get enough heat or cool air to feel comfortable.

It Will Break Down Often

If the mini split is not installed correctly, it is more likely to break down frequently. The parts wear out quickly on an overworked system. This problem occurs when the system’s too big or too small for the space. Or if something’s not hooked up right.

Whatever the cause, you’ll end up with large repair bills,

It Won’t Last As Long As It Should

Ductless systems can work for 20 years or more. A system that breaks down a lot won’t last that long. All the extra wear and tear shortens the lifespan.

You Can Damage Your Home

Installing a mini split involves:

A mistake can lead to damage to your home. You also risk mold if water leaks from unsealed condensate lines. There’s also the risk of an electrical fire due to bad wiring.

You Can Injure Yourself Or Others

Electricity is not a hobby! A bad connection or overloaded circuit can cause a fire. Did you know that 1,070 civilians were injured and 430 people died from 2015 to 2019 due to electrical fires? That’s all according to the National Fire Protection Association.

I’ve also seen the damage to walls and furniture from 30-pound air handlers falling off walls. That’s not to mention what would happen to a person underneath a heavy unit when that happens.

You’ll Void The Warranty

Many mini split manufacturers have strict installation requirements and warranties. Read the fine print: The warranties are voided if a certified technician does not install the unit. 

You also need a tune-up or regular maintenance once or twice a year.

Otherwise, you’re stuck paying for repairs even if there’s a problem with the manufacturing.

Can I Install Ductless AC Myself?

While a homeowner can install a ductless AC on their own, it’s not recommended. DIY installations don’t come with warranties. HVAC installations require professional load calculations. And, there’s the risk of property damage and injury from improperly-installed units.

Steps to Installing a Mini Split

We highly recommend a professional mini split installation due to the risks of a DIY project. If you’re still curious about what it entails, I’ll take you through the steps here. Hopefully, you’ll see why you need a professional.

Load Calculation

The load calculation determines the size of the heat pump and air handlers: How many BTUs you need altogether and in specific parts of the house. The factors include square footage, room layouts, airflow, insulation, positioning of your windows, and much more.

Determining Indoor Locations

Next, determine the placements of indoor units based on the size of each room and their layouts. You also need to choose between high-wall, low-wall, and ceiling models. Put them on exterior walls if possible to make it easier to run the lines.

Determining Outdoor Location

Next is placing the heat pump, or outdoor unit. Keep it close to the indoor units, make it accessible, and consider the street. You must also install the outdoor unit on a solid and level surface.

Mapping the Refrigerant and Condensate Lines

Once you’ve determined the locations of the indoor and outdoor units, you can map the refrigerant and condensate lines. The refrigerant lines are responsible for refrigerant cooling, while the condensate lines are responsible for water vapor that condenses back into liquid when the air cools. 

Installing the Heat Pump

The heat pump is the outdoor unit of the mini split air conditioner. You’ll need to understand the electrical connections. Sometimes, you’ll need special equipment to do it right.

Installing the Air Handlers

The air handlers are the indoor units of the mini split air conditioner. They are responsible for distributing the conditioned air to the rooms. The indoor unit is usually mounted on the wall. Then, drill a hole in the wall for the refrigerant lines, power cables, condensate drain, and suction tubing.

Running Wires And Lines

Finally, run the power cables and refrigerant lines from the outdoor unit to the indoor units. You will also need to install conduit to protect the wires and lines from damage.

Frequently-Asked Questions about DIY Mini Split Installations

You can always speak to one of our certified experts about installing a mini split in your home. They also offer free consultations. In the meantime, here are a few more frequently-asked questions. 


Do Mini Splits Come Pre-Charged?

Mini splits come pre-charged with the refrigerant necessary to transfer heat, or thermal energy, between the indoor and outdoor units. The charge is determined by the size of the system, meaning how many BTUs it can provide.

How long does it take a professional to install a mini split?

It usually takes a professional one day to install a single-zone mini split air conditioner. A multi-zone system can take up to a week, depending on the number of air handlers and their placement inside. The work is usually non-invasive and doesn’t require demolition or construction.

How Much Does Mini Split Installation Cost?

The cost of installing a mini split air conditioner varies depending on how many air handlers and whether the system will provide heat all winter. Single-zone ductless AC installs start at around $3,500. Multi-zone systems with strong heating capability run up to $20,000. Check for rebates, tax write-offs, and federal incentives to bring down your price.

Click here to learn more about the benefits of a mini split installation in your State College, PA home or anywhere in PA, NJ, DE, or MD.