Free sizing tool · MRCOOL® DIY® 5th Gen

Find your mini-split in two minutes.

Tell us your rooms. We'll size every zone, match an MRCOOL-approved system, and build your parts list — condenser to copper.

2 minTo size your system
$0Shipping, every order
7-yearCompressor warranty
No vacPre-charged lines

Add each room you want to heat and cool. One room gets a single-zone kit; two to six rooms get a multi-zone system. We size each room from MRCOOL's coverage ratings.

Ceiling height
Climate

We've pre-filled the size for each room. Change a size or style if you like — we'll keep checking it against MRCOOL's matchups.

Pre-charged Quick Connect® line sets, sized to each air handler. Measure the run from the indoor unit to the condenser and round up.

Total line length: 0 ft

Optional add-ons that make the install cleaner and last longer. Tap to add.

You'll also need (not sold here)
  • Outdoor service disconnect — a weatherproof shut-off within sight of the condenser. Required by code in most areas.
  • Electrical whip — the flexible conduit that runs power from the disconnect to the condenser.
Pick these up at a local supply house, or have your electrician bring them.

Here's everything in your build. Tap any item to see its full specs.

Browse the full catalog
Free shipping, same-day dispatch 7-yr compressor / 5-yr parts No vacuum pump or special tools Real install help
Reviews

From people who did it themselves.

5.0
from 4 reviews
“I knew my old system was old, and I was nervous about what to replace it with. Our whole house now runs on MRCOOL, and the savings were instant.”
JasonWhole-house MRCOOL
“Energy bills were getting so high. It's such a relief every month to see 30% savings.”
Jessica
“The flexibility of the multi-zone allowed for something my old system could never do. It runs so quiet, I can't even tell it's on.”
JoshMulti-Zone owner
“My husband installed this in an afternoon — I'm so proud of him. He's pretty handy, but this was a real DIY system, and it works amazing.”
MichelleDIY install
Questions

Straight answers.

Still stuck? Email us — a real person who's installed these will write back.

Do I really not need an HVAC tech?

For the refrigerant side, no. The line sets come pre-charged and seal with hand-tightened Quick Connect® fittings — no vacuum pump, gauges, or refrigerant handling. Electrical work should follow your local code.

115V or 230V — which do I need?

The 9K and 12K single-zone systems run on 115V. The 18K, 24K, and 36K systems and every multi-zone condenser run on 230V. Either way the unit gets its own dedicated circuit.

Single zone or multi-zone?

Single zone is one outdoor unit feeding one indoor unit — perfect for a garage, shop, or one big room. Multi-zone runs up to six indoor units off one outdoor condenser, each with its own temperature.

What if 25 feet of line set isn't enough?

We carry 35 ft and 50 ft pre-charged line sets, plus coupler kits for longer runs. Match the line set to the indoor unit's BTU size.

What's the warranty?

7 years on the compressor and 5 years on parts, plus eligibility for the MRCOOL® Care Program. See MRCOOL®'s terms for registration details.