Mini-Split Installation: How to Install a Mini-Split in 4 Steps

Mini-Split Installation: How to Install a Mini-Split in 4 Steps

Blueridge Ductless Mini-Split AC Installation - Alpine Home Air

Thinking about installing a ductless mini-split? Many of our customers choose to do the majority (90%) of the installation themselves and then hire a pro for the final start-up. Our DIY mini-splits allow customers to complete 100% of the installation on their own. 

In this article, Alpine’s HVAC experts explain the process of installing a mini-split system with wall-mounted air handler in four easy steps.

Preparing for Mini-Split Installation

Before diving into a ductless mini-split installation, you must consider several critical factors to ensure efficient performance and maximum comfort, regardless of how you plan to use your system and under what circumstances.


Sizing Your Mini Split AC

Properly sizing your mini-split AC system is paramount.

An oversized system can result in short cycling, reduced efficiency, and inadequate dehumidification.

Conversely, an undersized system won’t be able to cool your space effectively.

One of the best ways to ensure that your system is neither oversized nor undersized is to conduct a load calculation with professional help or online tools.

An accurate load calculation will help determine the right size system for your needs.


Location and Placement

The location of your indoor unit (or indoor units) and your outdoor unit can significantly impact your system’s efficiency.

For indoor units, ensure you install each unit in a location with unobstructed airflow. This ensures optimal distribution of the conditioned air throughout the room or zone.

Take some time also to consider the height at which you want the indoor unit to be mounted, assuming you are using wall units.

An optimal height for airflow is typically about seven feet above the floor.

Place outdoor units on a stable surface with ample clearance for proper airflow. Ensure they are shielded from direct sunlight and excessive debris to prevent overheating.

Electrical Requirements

Mini Split AC systems require specific electrical considerations. You’ll need a dedicated circuit with the appropriate voltage and amperage capacity to power the indoor and outdoor units.

Most mini splits are compatible with 220V wiring commonly required by larger household appliances. Some smaller, single-zone systems (12,000 BTU or lower) are configured to run on 110-120V. Make sure to verify your mini-split’s voltage requirements before you begin installation.

Even someone fully committed to a DIY mini-split installation may want to consult an electrician before starting.

A licensed electrician can ensure that your electrical system meets all the requirements and runs smoothly and without risks.

Addressing these steps before your mini-split install guarantees years of comfort and long-term use for your home or office’s heating and cooling needs.

How to Install a Mini-Split in 4 Steps

Step 1: Mounting a Ductless Mini-Split
1 Mount
  • Outside: Install the condenser on a pad or bracket and in a convenient location.
  • Inside: Attach the included mounting plate on the wall where you want to install the air handler.
  • Using a hole saw, drill through your wall at a slight downward angle, adjacent to the lower right-hand side of the mounting plate. Insert wall sleeve, if desired.
  • Hang the indoor unit on the mounting plate while running the refrigerant lines, wiring, and drain tubing through the hole to the outside.
Step 2: Connecting Line Sets
2 Connect
  • Using a torque wrench, secure the refrigerant lines to the connectors on the indoor unit and then the outdoor unit.
  • Connect the wiring between indoor and outdoor units. Make sure to match each color of wire to the corresponding terminal.
  • Discharge the condensate line away from the wall and to the outside.
Step 3: Electrical Work
3 Electrical

We recommend hiring an electrician for this portion of the job if you are not trained to work with high voltage electricity.

  • Turn off power at the breaker box.
  • Depending on your particular model, run 220- or 110-volt power from a dedicated circuit on your breaker panel to a disconnect box located near the outdoor unit. 
  • Install an electrical whip (weatherproof power wiring) connecting the disconnect box to the outdoor unit.
  • Turn the power back on at breaker box.
Step 4: Start Up
4 Start-Up

A. Conventional Mini-Split: Hire a Pro

Your HVAC contractor will:

  • Do a pressure test to check for leaks
  • Pull a vacuum on the refrigerant lines
  • Release the refrigerant from the condenser into the system
  • Add refrigerant if the refrigerant lines are longer than the factory precharge in the system
  • Startup and test the system

B. DIY Mini-Split: Self Start-Up

  • Release the refrigerant from the outdoor unit into the system using an Allen wrench.
  • Check for leaks: Use a spray bottle with soapy water where the line sets connect. 
    • If there are leaks, retighten the line set connections to the proper torque.
  • Turn on the system.

After the Mini-Split Installation

Your ductless mini-split system is up and running. Now what?

As with many home improvement items, a mini-split needs ongoing attention to ensure it continues to work as it should. After the installation is complete, don’t forget the following:

Maintaining Your System:

Once your mini-split system is successfully installed, ongoing maintenance is essential to keep it operating efficiently and prolong its lifespan. Here are some tasks to keep in mind:

  1. Regular Cleaning: Clean or replace air filters as recommended by the manufacturer. Dirty filters can reduce system efficiency and indoor air quality.
  2. Coil Cleaning: Periodically clean the indoor and outdoor coils to remove dust and debris hindering heat exchange. Be cautious when cleaning delicate coil fins.
  3. Check for Leaks: Inspect refrigerant lines and connections for any signs of leaks. If you notice refrigerant leaking, contact a licensed HVAC technician for repairs.
  4. Condensate Drain Maintenance: Ensure the condensate drain line is clear and not debris-logged. A clogged drain can lead to water damage.
  5. Lubricate Moving Parts: If your mini-split has moving parts, such as fan motors, lubricate them according to the manufacturer’s recommendations.

Though many of the maintenance tasks are things you can tackle yourself, having an HVAC professional do an annual check-up on your system is always a good idea to ensure everything is running well and no hidden issues are present.

Mini-Split Installation Videos

Watch the installation of a conventional mini-split from start to finish:

Watch a DIY mini-split installation here:

*Note that in newer DIY models, the line set comes packaged with the condenser and must be attached to both inside and outside units.

Mini-Split AC Installation Troubleshooting and FAQs

Whether you choose a DIY mini-split installation or a professional one, there’s a good chance you may encounter a few challenges while installing your mini-split AC system.

Here are some common installation challenges and frequently asked questions:

Common Installation Challenges

  1. Refrigerant Handling: One of the most critical aspects of Mini Split AC installation is handling refrigerant. A common challenge is ensuring no leaks in the refrigerant lines, which can lead to system inefficiency or malfunction. Regularly check for leaks and ensure proper sealing.
  2. Electrical Wiring: Proper electrical connections are crucial for the system’s safety and performance. Challenges may include correctly wiring the indoor and outdoor units, ensuring adequate voltage, and preventing electrical shorts. Always follow the manufacturer’s wiring diagrams and guidelines.
  3. Drainage Issues: Mini Split AC systems generate condensate, which must drain properly. A blocked or improperly routed drain line can lead to water damage. Regularly inspect and clean the drain line to prevent clogs.
  4. Mounting and Placement: Incorrect positioning of the indoor and outdoor units can affect system efficiency and airflow. Ensure the indoor unit is at an optimal height and location for even cooling or heating. Place the outdoor unit on a stable surface with proper clearance for airflow.
  5. Communication Errors: Mini Split AC systems usually require communication between the indoor unit(s) and the outdoor unit for temperature control. Troubleshooting communication errors may involve checking wiring, checking settings, and ensuring no remote control issues.

Common Questions about a Mini Split Installation

Do I need to hire a professional for installation?

While professional installation is recommended for safety and warranty compliance, experienced DIYers may opt for self-installation.

How long does the installation process take?

Installation time varies but usually takes several hours to a full day, depending on system complexity.

Can I install multiple indoor units with one outdoor unit?

Yes, multi-zone systems allow you to connect multiple indoor units to a single outdoor unit, reducing installation costs.

What maintenance is required after installation?

Regular cleaning of air filters, condenser coils, and drainage lines, as well as annual professional maintenance, is recommended.

Is a permit required for installation?

Local building codes may require permits for HVAC installations. Check with your municipality for specific requirements.

Proactively addressing these challenges and questions can help ensure a smooth Mini Split AC installation process, allowing you to enjoy efficient heating and cooling in your space.

Have More Questions? Alpine is Your Place for Answers!

We have answers! For more information about installing a ductless mini-split, contact the HVAC experts at Alpine. We can help you find the best mini-split system for your space, budget, and particular needs. Here at Alpine, we’ve been making customers happy since 2002. We have thousands of 5-star reviews and an A+ rating from the BBB

Blueridge ductless mini-splits–Alpine’s exclusive brand–are made to our specifications by the world’s largest, most reputable HVAC manufacturer and have the highest online product ratings of all mini-split brands. When you purchase a Blueridge mini-split from Alpine, you get:

The exceptional Blueridge Ductless Mini-Split Warranty covers five years for parts and seven years for the compressor (heat pump). What’s more, Alpine’s in-house warranty processing means support or replacement parts are just a phone call away. But here’s where the Blueridge warranty really shines: while many mini-split brands warrant their product only when installed by a licensed contractor, Blueridge’s warranty covers the do-it-yourselfers as long as the unit has been installed correctly.

For more information, call or email us today!

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