Split Ductless AC Installation: Step-by-Step Guide

When it comes to cooling your space efficiently, split ductless AC installation offers a sleek and effective solution. Installing a ductless air conditioner can transform your comfort levels while saving on energy costs. Say goodbye to bulky units and hello to seamless integration with your decor. With a ductless AC unit, you get the best of both worlds – powerful cooling without the hassle of extensive installation. Enjoy precise temperature control in different zones of your home, all with minimal disruption to your walls or ceilings.

Key Takeaways

  • Ensure you understand the specifics of ductless AC systems before starting the installation process.
  • Choose the right system size and type based on your space requirements and cooling needs.
  • Properly prepare the installation area by clearing obstacles and ensuring adequate space for both indoor and outdoor units.
  • Have all necessary materials ready, including mounting brackets, refrigerant lines, and electrical wiring, before beginning the installation.
  • Pay close attention to the power supply setup to ensure safe and efficient operation of your ductless AC unit.
  • Follow the manufacturer’s instructions carefully when installing the indoor unit, outdoor unit, and configuring the remote control for optimal performance.

Understanding Ductless ACs


Ductless air conditioner systems consist of an outdoor compressor unit and one or more indoor air-handling units. These units are connected by a conduit that houses the power cable, refrigerant tubing, suction tubing, and a condensate drain.

The indoor unit typically includes a fan to distribute the conditioned air and an evaporator coil to cool or heat the air. The outdoor unit contains the compressor, condenser coil, and expansion valve.


Installing a ductless mini-split system offers several advantages. Energy efficiency is a key benefit as these systems do not experience energy losses associated with ductwork. They also allow for zone control, enabling different rooms to be set at different temperatures according to individual preferences.

Another significant advantage is easy installation due to the absence of ductwork. This results in minimal disruption during installation and can be completed relatively quickly compared to traditional HVAC systems.


Ductless AC installations are highly versatile, making them suitable for various settings. In residential homes, they provide an excellent solution for room additions, where extending existing ductwork may not be feasible.

In commercial spaces such as offices, ductless systems offer flexibility in cooling or heating specific areas without affecting the entire building’s temperature. In historical buildings or structures with architectural constraints, ductless ACs provide a viable cooling solution without compromising the building’s aesthetics.

Choosing the Right System

BTU Sizing

When selecting a split ductless AC installation system, determining the appropriate BTU size is crucial. The BTU rating indicates the cooling capacity of the unit. Undersized units will struggle to cool effectively, while oversized ones can lead to energy inefficiency.

It’s essential to calculate the required BTUs based on factors like room size, insulation quality, and sunlight exposure. An accurate BTU calculation ensures optimal cooling performance and energy efficiency.

DIY Mini-Split Systems

Opting for a DIY mini-split installation offers a cost-effective way to install a ductless air conditioner. These systems come with pre-charged refrigerant lines, making them easier to set up without professional help.

The cost range of DIY mini-split systems varies depending on the brand, features, and BTU capacity. While they are more affordable than traditional central AC units, it’s crucial to consider additional expenses like mounting brackets and electrical wiring.

Preparing for Installation

Level Surface

Prepare the installation area by ensuring a level surface for the condenser. This is crucial to maintain the stability and efficiency of the unit.

A level surface helps in proper drainage of condensation and ensures that the unit operates smoothly without any disruptions.

Line Set Cover Kit

Understand the significance of having a proper line set cover kit for installation. These kits conceal the pipes connecting the indoor and outdoor units, enhancing the overall aesthetics.

By using a line set cover kit, you can protect the tubing from external elements, prolonging its lifespan and maintaining optimal performance.

Steps Preparation

Learn about the steps needed to prepare for a ductless AC installation. Start by marking where the hole will be drilled for piping connections.

Ensure that all necessary tools such as drills, screws, and anchors are readily available before commencing the installation process.

Necessary Materials Overview

Condenser Wall Brackets

To ensure a successful ductless AC installation, you will need condenser wall brackets. These brackets provide sturdy support for the outdoor unit, ensuring it is securely mounted on the wall. The condenser wall brackets are typically made of durable materials such as galvanized steel to withstand outdoor conditions.

Plastic Condenser Pad

Another essential component for installing a ductless AC unit is a plastic condenser pad. This pad serves as a stable base for the outdoor unit to rest on, protecting it from ground-level debris and moisture. The plastic material of the condenser pad is weather-resistant and provides insulation to prevent damage to the unit.

Refrigerant Line Set

A crucial element required for a split ductless AC installation is the refrigerant line set. This set consists of two copper lines that connect the indoor and outdoor units, allowing refrigerant to flow between them. It is essential to ensure proper sizing and insulation of the refrigerant lines to maintain optimal cooling efficiency.

Electrical Wiring Components

For installing a ductless air conditioner, you will need various electrical wiring components such as wire connectors, electrical tape, and conduit. These components are necessary for safely connecting the indoor and outdoor units to the power supply. It is important to follow electrical codes and guidelines when installing these components to prevent any safety hazards.

Mounting Hardware

To secure the indoor unit during ductless AC installation, you will require mounting hardware such as screws, anchors, and brackets. These hardware items are used to attach the indoor unit securely to the wall or ceiling, ensuring stability and proper airflow distribution within the room.

Power Supply Setup

Existing Circuit Assessment

When considering power supply setup for a split ductless AC installation, the first step is to evaluate if drawing power from an existing circuit is feasible. Check the load capacity of the current circuit to ensure it can handle the additional electrical requirements of the new unit.

It’s crucial to avoid overloading an existing circuit, which can lead to tripped breakers or even fire hazards. If the existing circuit has ample capacity to accommodate the ductless air conditioner, you can proceed with connecting it without the need for a new dedicated circuit.

New Dedicated Circuit Requirement

In cases where cables from an existing circuit are insufficient to power the ductless AC unit, installing a new dedicated circuit becomes necessary. A dedicated circuit ensures that the air conditioner receives a stable and uninterrupted power supply, reducing the risk of electrical issues.

By setting up a separate circuit solely for the ductless AC unit, you eliminate potential interference from other appliances sharing the same power source. This enhances efficiency and performance while minimizing the chances of electrical malfunctions due to power fluctuations.

Project Complexity Influence

The complexity of a split ductless AC installation project greatly influences power supply setup requirements. For straightforward installations in single rooms or small spaces, utilizing an existing circuit may suffice, provided it meets the necessary electrical standards.

However, larger projects involving multiple indoor units or more extensive setups often demand new dedicated circuits to ensure optimal performance and safety. These intricate installations require meticulous planning to determine the most efficient and reliable power supply configuration.

  • Opting for a new dedicated circuit offers enhanced safety measures and prevents potential electrical complications.
  • Utilizing an existing circuit may expedite installation but could pose risks if not adequately assessed beforehand.

Installing Indoor Unit


When installing the indoor unit of a split ductless AC, ensure it is placed high on the wall for optimal airflow distribution. This positioning helps cool or heat the room efficiently.

Mount the indoor air conditioner at least seven feet above the floor to avoid obstacles and ensure proper air circulation. This height also prevents interference with furniture and other objects in the room.


Secure the indoor unit mounting plate on the wall using a level to ensure it is straight. The mounting plate provides support for the indoor air handler, keeping it stable and secure.

Attach the refrigerant line, power cable, and condensate drain tube to the designated ports on the indoor unit. Properly connecting these components ensures smooth operation and efficient cooling or heating.

Installation Process

Begin by drilling a hole through the wall to connect the indoor unit to the outdoor condenser. This hole allows passage for the refrigerant line, power cable, and condensate drain tube.

Carefully thread the refrigerant line through the hole while ensuring there are no kinks or bends that could obstruct refrigerant flow. Any obstructions can impact system performance and efficiency.

Connect the refrigerant line to both the indoor unit and outdoor condenser following manufacturer guidelines. Proper connection is crucial for maintaining refrigerant pressure levels and overall system functionality.

Maintenance Tips

Regularly clean and maintain your ductless AC system’s indoor unit to ensure optimal performance. Dust accumulation can hinder airflow and reduce efficiency over time.

Inspect the radiant floor heating beneath or around the indoor unit if applicable. Ensure that there are no leaks or damages that could affect system operation or efficiency.

Setting Up Outdoor Unit

Wall Brackets

To install the outdoor condenser unit, utilize plastic wall brackets for secure mounting. Position them correctly.

Ensure the outdoor unit is placed at an optimal height for efficient heat dissipation and maintenance accessibility.

Proper Positioning

Positioning the outdoor unit plays a crucial role in the overall efficiency of the ductless AC system. By placing it strategically, you can ensure better airflow and performance.

The correct placement will also prevent any obstructions that could hinder the unit’s functionality or maintenance procedures.

Efficient Heat Dissipation

Understanding the steps involved in setting up the outdoor unit is essential for ensuring proper operation. The outdoor unit is responsible for releasing heat absorbed indoors.

Remote Control Configuration

Handheld Controller

To adjust the room temperature in the split ductless AC system, configure the handheld controller. This device allows you to easily control the cooling or heating settings within your space. The process involves setting the desired temperature and selecting the fan speed for optimal comfort.

Additional Control Options

e ductless air conditioner models offer extra features, such as Wi-Fi and Bluetooth connectivity. These options enable you to control your AC unit remotely through your smartphone or other smart devices. By utilizing these advanced technologies, you can conveniently adjust the temperature even when you are not at home.

Setting Up and Using Remote Control

When installing a ductless AC unit, it is crucial to understand how to set up and use the remote control effectively. Begin by inserting batteries into the controller and ensuring it is properly synced with the indoor unit. Familiarize yourself with the various buttons and functions on the remote to regulate the temperature and fan settings accurately.

Closing Thoughts

You’ve now grasped the essentials of installing a split ductless AC unit. From understanding the system to setting up the indoor and outdoor units, you’re well on your way to enjoying a cooler environment. Make sure you have all the necessary materials ready before diving into the installation process. Your comfort is just a few steps away!

Remember, proper installation ensures optimal performance and longevity of your ductless AC unit. If you encounter any challenges during the setup, don’t hesitate to seek professional assistance. Stay cool and enjoy the benefits of your newly installed split ductless air conditioner!

Frequently Asked Questions

Is installing a split ductless AC unit a DIY project?

Installing a split ductless AC unit is best left to professionals due to the electrical and refrigerant work involved. Professional installation ensures proper setup, optimal performance, and warranty coverage.

What are the benefits of choosing a ductless AC system?

Ductless AC systems offer energy efficiency, individualized comfort control, easy installation, quiet operation, and improved indoor air quality. They are also versatile for heating and cooling multiple areas in homes or offices.

How do I prepare for the installation of a ductless AC unit?

Prepare for installation by selecting an ideal location for the indoor and outdoor units, ensuring proper electrical supply, clearing the installation area of obstructions, and scheduling professional installation services for a seamless process.

What materials are essential for installing a ductless air conditioner?

Essential materials include mounting brackets, refrigerant lines, line hide covers, condensation drain tubing, electrical wiring components, wall anchors, screws, remote control batteries, and any additional accessories recommended by the manufacturer.

Can I control my split ductless AC unit remotely?

Yes, most modern split ductless AC units come with remote control functionality. You can conveniently adjust temperature settings, fan speed, modes (cooling/heating), timers, and other settings using the provided remote control for enhanced comfort and convenience.


Get the ultimate step-by-step guide for split ductless AC installation. Expert tips on installing a ductless air conditioner unit.