How to DIY Mini Split Installation & Save Big!
Every homeowner is looking for the best cooling and heating option for their home. Though central air conditioning was all the rage once, mini-splits are becoming increasingly popular because of their convenience and efficiency. The countless advantages of ductless air conditioners makes mini-splits a no-brainer for most people, and easy mini-split installation is an added advantage.
Mini-split installation is much easier than central air conditioning since there is no ductwork involved. If you’re even mildly handy with tools and electronics, you can DIY most of the mini-split AC installation and save big bucks. While you may need to purchase separate equipment for some mini-splits, there are DIY mini-split options available that include a complete bundle.
Factors to Consider When Buying & Installing a Mini-Split
Before you make your purchase and get on with the installation process, the following factors are important to consider:
1. Size of Mini-Split
You will need a professional to estimate what mini-split size would be the best for your needs. Under sizing or oversizing a mini-split is a common mistake homeowners make, leading to poor cooling and higher bills. A properly sized air conditioner will meet your heating and cooling needs for the foreseeable future.
2. Type of Mini-Split
You need to consider the space and your needs before purchasing your mini-split air conditioner. The most common mini-split choices include single-zone and multi-zone mini-split air conditioners as well as wall-mounted, floor-mounted, and ceiling cassette types. You’ll have to identify the area and specify your heating and cooling needs before making the final selection.
A split system air conditioner must be placed on an exterior wall for effortless installation and preferably near the middle of a room to provide even cooling throughout. Leave at least 2 inches of empty space above the indoor unit.
Outdoor units should have plenty of open space around them for ease of airflow. Choose a shaded area that is easily accessible for maintenance. It’s best to place them slightly higher than the indoor unit to prevent the compressor from fighting gravity as the refrigerant is circulated.
4. Energy Efficiency
EER and SEER ratings are an indicator of an air conditioner’s efficiency. As a general rule, the higher the rating, the better. For example, upgrading from a SEER rating of 9 to 13 can reduce total power consumption by an impressive 30%.
Mini-Split AC Cost
A ductless mini-split costs $1500 to $2000 per ton of cooling capacity. This is approximately 30% more than the cost of a central AC, excluding the ductwork. However, ductless mini splits make up for it with their easy installation and energy efficiency.
Mini-Split Installation Cost
A professional mini-split AC installation can set you back a couple of grand. The average ductless mini-split installation costs $3000 for a 12,000 BTU system. This figure can go up to $14,500 depending on the type of unit you are installing and the complexity of the installation.
If you don’t want to spend a lot of money on mini-split installation, the advent of DIY-friendly mini-splits, such as those made by MRCOOL, has made it easier than ever to install your mini-split yourself.
How to Install a Mini-Split AC Yourself?
If you’re planning to DIY your mini-split installation, you must choose a mini-split that supports the DIY installation. In conventional mini-splits, even though you can complete most of the installation yourself, you still need a professional to come in at the end and charge the refrigerant lines. A DIY-friendly mini-split will come with the refrigerant precharged.
A mini-split has two components, an indoor air handler, and an outdoor condenser unit. The two components are connected together by copper tubing, which allows the refrigerant to flow between them.
The following is a general guide for mini-split installation; however, most mini-splits come with their own installation manual. You must read it thoroughly before beginning any installation work. Pay special attention to the tools required as well as the safety instructions.
Once you’ve done that, unbox the mini-split and check the components for any defects. Once you’ve made sure all the parts appear in order, you can get started with the installation process.
Tools Required for Mini-Split Installation
For DIY mini-split installation, you will need the following tools:
- Adjustable Wrench
- Torque Wrench
- Drill & Drill Bits
- Hole Saw
- Utility Knife
- Wire Cutter & Wire Stripper
- Phillips Head Screwdriver
- Flat Lay Screwdriver
- Safety Glasses
- Work Gloves
Step-by-Step Guide to Mini-Split Installation
Once you’ve read the instructions and gathered all the tools, you can follow this step-by-step guide on how to install a mini-split air conditioner:
1. Decide the Location
The first and most crucial step when installing your mini-split is deciding the location. Install your mini-split on an exterior wall for best results, so you have no trouble connecting the indoor unit to the outdoor unit. For wall-mounted mini-split air conditioners, the indoor unit should be at least 6 feet above the ground.
2. Clear the Area Around the Outdoor Condenser Unit
After you’ve decided the wall you will be installing your mini-split on, clear the area where you plan to place the outdoor condenser unit. Shrubs near the outdoor unit can cause performance issues in the long run by clogging the outdoor unit. Clearing the area of any foliage will save you a lot of headaches in the future.
3. Stabilize the Outdoor Condenser Unit
The outdoor condenser unit needs something to rest on. That can either be a concrete pad or a plastic pad. Fortunately, you can build the concrete pad yourself if you do not wish to involve a professional. If you do not want to place it on the ground, you can also mount it to a wall using condenser wall brackets.
Some prefer to keep it on the ground to prevent wall vibrations. If you get a lot of snow during winter, it’s ideal to keep the condenser above the ground.
4. Locate Wall Studs & Install the Back Plate
One of the most important things to consider when installing a mini-split is the location of your wall studs. To securely hang anything heavy, you need to attach it to your wall studs.
Follow these steps to find a wall stud:
- Tap the wall with your knuckles. If you hear a hollow sound, tap to the left or right until you hear a muffled sound. That is the wall stud.
- Tap to the studs’ sides to figure out their width. Mark with a pencil where you think the wall stud ends.
- Where the wall stud ends, measure 16 inches to the side to locate the other wall stud (wall studs are required to be 16 inches apart by code).
- Mark the edges of each wall stud with a pencil.
- Finally, drill a small hole where you believe the wall studs are. If you hit wood, you’ve located a wall stud correctly.
Your AC manufacturer will have included a backplate and a cardboard template in the mini-split packaging. The indoor unit will be mounted on the backplate. Place the cardboard template on the wall. The cardboard template only acts as a guide; use it to figure out where you will drill the backplate into the wall. The holes on the template (which indicate where the backplate will be drilled into the wall) need to be on the studs. Next, use a pencil to mark the wall where you will attach the backplate.
Now it’s time to attach the backplate to the wall:
- Place the backplate on the wall. Drill it into place on one side.
- Use a level to check if the backplate is perfectly horizontal.
- Then drill it into place on the other side.
- Ensure the backplate is securely attached to the wall as it needs to bear the weight of the indoor air handler.
5. Determine the Location of the Hole
Next, you need to decide the location of the hole that will connect the indoor and the outdoor unit. The wall template will specify the hole’s location. Use a drill to mark a small spot according to the template. The mark will serve as your guide for the next step.
6. Drill the Hole
Next, use a 3.5-inch hole saw to drill a hole through your wall. The mark you made in the previous step should be the center point for your hole saw.
7. Insert the Sleeve into the Hole
Once the hole is ready, push the provided wall sleeve through the wall. Note how far it sticks out on the other side. Ideally, it should be as close to the wall as possible. Use a utility knife to cut the excess wall sleeve.
8. Position the Refrigerant Line and Drainpipe Correctly
On the right-hand side of the AC, you will find the drainpipe and refrigerant lines. Carefully bend the pipes so they form a 90-degree angle with the back of the air conditioner.
9. Mount the Indoor Unit
Now it is time to mount the indoor unit.
- Stand on a secure ladder (it would be best to have at least one person to support the ladder).
- Lift the air conditioner, and pass the drainpipe and the communication lines through the sleeve.
- Then, securely connect the indoor air handler to the wall plate. You should hear a click sound when the air conditioner has been securely attached to the wall plate.
10. Add Neoprene to the Wall Sleeve
Neoprene is a synthetic rubber that will create a secure seal around the drainpipe, refrigerant lines, and communication lines.
- Next, go outside and bend the drainpipe and connection lines another 90-degrees so they are flush with the wall.
- Then add the protective neoprene inside the wall sleeve.
- Securely attach the outside wall sleeve cover.
11. Connect the Condensate Drain Hose and Refrigerant Lines
- Attach the condensate drain hose to the pipe.
- You will find a line set precharged with a refrigerant with your DIY-friendly mini-split. Uncoil the amount you think you will need to reach from the indoor handler to the condenser.
- Unscrew the color-coded caps at the end of the refrigerant lines near the indoor air handler.
- Use two wrenches to attach the line set to the refrigerant lines securely. Do the same thing for the refrigerant lines near the condenser.
12. Release the Refrigerant
- Once the refrigerant lines are secure, remove the valve covers on the condenser.
- Use an Allen wrench to open the valve by turning it anticlockwise until it stops.
- Next, use soapy water to check for leaks. Spray soapy water over the joints, if you see any large bubbles forming, you have a leak, or you did not connect the refrigerant lines properly.
In case there are no leaks, replace the valve covers and tighten them with a wrench.
If you do see large bubbles forming, use two wrenches to confirm the refrigerant lines are securely attached. If the refrigerant lines are securely attached, you most likely damaged the line set during installation. In this case, you will have to contact a seasoned HVAC professional who will identify the source of the leak, patch it, and recharge your system with refrigerant. Never attempt to fix a refrigerant leak yourself, as handling AC refrigerant can be hazardous unless you are an expert.
13. Soundproof the Refrigerant Connections
- Wrap the refrigerant connections near the indoor air handler with sound dampening pads.
- Then thoroughly wrap them with vinyl tape. If you want a sleek look, you can also use a line set cover.
14. Install the Electrical Connection
Unless you are a certified electrician, installing the electrical connection yourself is not something you should ever attempt. Any local electrician can help you wire your newly installed air conditioner, and you’ll be all set to enjoy perfect temperatures inside your room.
Make Your Mini-Split Air Conditioner Smart
Now that your mini-split air conditioner is up and running, it’s time to take your comfort to the next level. You can make your mini-split smart in no time just by connecting it to a smart AC controller. With features like geofencing, weekly scheduling, Comfy Mode, you can automate your home climate without worrying about home temperature anymore!
Here’s how to DIY a smart air conditioner!
Now that you know how easy it is to install a ductless mini-split, there’s no doubt that your next mini-split installation will go without a hitch. Just make your safety a priority, and you should be good to go! Once you install your mini-split and make it smart, your air conditioning should be economical as well as comfortable.