Let our Mini Split Configurator build the system for you based on the specifics of your space, rather than the components themselves. Use this tool if you’re not sure what size system or how many zones you need. It will build a system for you based on the size of your space(s).

Use our multi-zone matchup tool to match up air handlers with the multi-zone condenser of your choice and then use it to complete the build of your system. Use this tool if you want a system for 2-5 rooms up to 2,000 sq feet in total and you want to start by picking your condenser.

Call one of our HVAC expert account reps who can talk you through the process and help you figure out what you need for your system. Use this if you want a live person to talk you through your system build.

Every customer gets assigned an account rep and if you call for help that person will be your rep from then on.

Manually choose each component for your system and put it together yourself without the suggestions given by our other builders. Use this tool if you already know exactly what you need and you just need to put it together.

There are some circumstances in which MRCOOL customers can "fall through the cracks" in the manufacturer warranties. That's why we created "Direct Protect," our own exclusive extended warranty on refrigerant and labor (even if you do the install yourself). All mini-split systems come with this additional warranty for free, only if you buy from MRCOOL Direct.

MRCOOL's patented DIY technology can save you thousands on the install, even if you're hiring a professional to do it. And our eco friendly options save you big money on your utility bills.

Selecting the right location for both the indoor and outdoor units is crucial for optimal performance:

1. Indoor Unit: Ideally placed high on a wall in a central location within the room for even air distribution.
2. Outdoor Unit: Should be located on a stable surface away from obstructions like trees or fences that could block airflow.

1. Use a stud finder to locate wall studs where you’ll mount the indoor unit.
2. Hold up the mounting bracket against the wall where you want to install it.
3. Use a level to ensure it's straight before marking drill holes.
4. Drill holes into the wall at marked points and secure the bracket using screws.

You’ll need to create a hole in your wall for connecting refrigerant lines between indoor and outdoor units:

1. Use your drill to create a hole approximately 3 inches in diameter through which pipes will pass.
2. Ensure that this hole slopes slightly downward towards the outside for proper drainage.

Similar to how you mounted your indoor unit:

1. Find an appropriate spot for your outdoor unit on solid ground or use brackets if mounting on a wall.
2. Securely attach it using bolts or screws according to manufacturer instructions.

Now it's time to connect refrigerant lines between both units:

1. Carefully feed refrigerant lines through the hole created earlier from inside out.
2. Connect these lines as per instructions provided in your MRCOOL kit—typically involving tightening fittings with wrenches.

Ensure that electrical connections are made safely:

1. Turn off power at circuit breaker before proceeding.
2. Follow wiring diagrams included with your kit; connect wires from both units according to color codes (usually black, white, green).
3. Secure connections with wire nuts or connectors as recommended.

Before powering up:

1. Double-check all connections—both refrigerant lines and electrical wires—to ensure they are secure.
2. Make sure there are no leaks by checking fittings after tightening them properly.
3. Contact your MRCOOL Direct account rep if you have any questions.

Once everything is connected correctly:

1. Turn on power at circuit breaker.
2. Follow startup procedures outlined in your manual; typically involves pressing buttons on remote control or unit itself.

You're all Done!

Control Heating & Cooling from Anywhere

If you have WiFi, you can control your HVAC system from anywhere where you have internet access.

Limited Lifetime | 7 Year Compressor & 5 Year Parts AND Direct Protect

Buy from MRCOOL direct and you get MRCOOL's manufacturer warranties and our Direct Protect Extended Warranty on Refrigerant and Labor, too.

Amazon Alexa & Google Assistant

The 4th Gen DIY® is fully compatible with Amazon Alexa and Google Assistant

Safety & Durability

The included DIYPRO® armored cable is shielded in coated flexible conduit providing higher mechanical protection and durability.

Now Available

Now you'll be able to heat and cool up to 5 rooms at a time with the MRCOOL® DIY® 5 Zone Multi-Zone unit.

One House, One Solution

Multi-zone technology gives you flexibility and control whenever and wherever you want it.

MRCOOL DIY doesn't require any expensive ductwork. Simply mount, connect, and enjoy.

Control the temperature of your space down to the degree using MRCOOL DIY's sensor technology.

Simply install MRCOOL DIY without the need for expensive tools or specialized training.

Outdoor Condenser Placement:

1. Location: Choose a location for the outdoor condenser. Ensure it's accessible for electricity via an outdoor disconnect.
2. Mounting: Decide whether to place the condenser on a ground pad or mount it to the wall.

Indoor Air Handlers:

1. Type: Choose between ceiling or wall-mounted air handlers.
2. Location: Preferably mount air handlers on an interior side of an exterior wall to allow condensate line to gravity drain. If mounting on an interior wall, a condensate pump will be necessary. Ceiling mounts come with a built-in pump.

Linesets carry refrigerant from the condenser to the air handlers. Measure the required lineset lengths carefully. Getting too short of a line set for your system can be a costly mistake. Use single linesets when possible for maximum performance (use a single 35' lineset rather than coupling two 16' linesets, for instance). For lengths over 50' you'll need to couple two linesets (a 50' and a 25' will give you 75' of coverage, for instance). No matter the length, do not couple the communication wire. You must use only one communication wire between the condenser to the air handler to avoid risk of voiding the manufacturer warranty. Minimum lineset length is 16 feet, and the maximum is 75 feet per line, with a total of up to 225 feet in multi-zone systems.

Protection: It's a good idea to cover your line sets with LineGuard to prevent insulation deterioration and enhance system efficiency. Make sure you order MRCOOL Lineguard along with your system so you're ready to install it with that protection.

Room Calculation:

• Number of Rooms/Zones: Identify how many areas you want to condition.
• Square Footage: Calculate the square footage of each room/zone. For rooms with ceilings over 8 feet, add 12.5% more square footage for each additional foot of height.
• System Matching: Choose air handlers based on the calculated size per room/zone and ensure the condenser matches the total required BTUs. Remember, a condenser can manage up to 5 rooms/zones in a multi-zone system and can only output the BTUs it's rated for, regardless of the rating of the air handlers.

If you aren't sure exactly what you need for your space, click the button below to use our Mini Split Configurator to put together the perfect system for you.

Still have questions? Call one of our account reps at 1-615-553-8118.