How to Choose the Perfect Airspool Solar Mini-Split

The no-nonsense guide to picking the right unit for your space, your climate, and your life.

What's in This Guide

1. The Basics: What Makes Airspool Different
2. Sizing Your Unit: BTUs and Square Footage
3. MS vs. HS Series: Which One Do You Need?
4. Single Zone vs. Multi-Zone: One Unit or Many?
5. The Window Unit: When It Makes Sense
6. Solar: Do You Need It Right Away?
7. Installation: Yes, You Can Actually Do This
8. The Guarantee That Changes Everything
9. Every Airspool Unit at a Glance
10. The Bottom Line

The Basics: What Makes Airspool Different

Look, you probably already know what a mini-split is. You're here because you've done the research. You know that ductless heating and cooling is more efficient than forcing air through a bunch of leaky ducts in your attic. You know that zoned comfort means you only pay to condition the rooms you actually use.

So let's skip the mini-split 101 lecture and get to what matters: Why Airspool, and which Airspool?

Here's what sets us apart:

• 5-minute connection. Not 5 hours. Not 5 days waiting for an HVAC tech. Five minutes. Our patent-pending Quick ’n’ Easy^TM system means you twist-to-connect pre-charged refrigerant lines. No vacuum pump. No nitrogen. No gauges. No torque wrench. The only tool you need is a drill (and we give you the bits).

• Solar-ready from day one. Every unit can run on solar, grid power, or both simultaneously. Solar always gets prioritized automatically. No batteries required. No external voltage controllers. Just click in your panels with standard MC4 connectors.

• Actually movable. Life happens. You might move. You might want to put the unit in a different room. With Airspool, you can unscrew, unplug, and reinstall it somewhere else. Try doing that with other mini-splits without voiding your warranty.

• Pre-tested before it ships. We run every unit on solar mode, grid mode, and hybrid mode at our Las Vegas facility before it goes in a box. If there's a problem, we catch it. Not you.

Now let's figure out which unit is right for you.

Sizing Your Unit: BTUs and Square Footage

BTU stands for British Thermal Unit. It's a measurement of heating and cooling capacity. The higher the BTU, the more space you can condition. Here's the simple breakdown:

A Note on Sizing: These are general guidelines. Your actual needs depend on ceiling height, insulation quality, sun exposure, and how many windows you have. When in doubt, size up. An oversized unit runs less often at lower capacity and still keeps you comfortable. An undersized unit runs constantly and never quite gets there.

For most people, a single 12,000 BTU unit handles the job. It's our best seller for a reason. But if you have a larger space or want to condition multiple rooms, keep reading.

MS vs. HS Series: Which One Do You Need?

This is the single most important decision you'll make when choosing an Airspool unit. It comes down to one thing: how cold does it get where you live?

The MS Series (Standard)

The MS12 and MS24 are our standard units. They heat effectively down to about 5°F outside temperature. If you live somewhere that rarely dips below freezing, these units will serve you well year-round.

The HS Series (Superheat)

The HS12 and HS24 feature Enhanced Vapor Injection (EVI) technology. In plain English: they keep pumping out heat when it's absolutely brutal outside, all the way down to -22°F. If you're in Minnesota, Maine, Montana, or anywhere that sees seriously cold winters, this is your series.

Quick Decision Guide

Choose MS (12 or 24) if your winters rarely drop below 5°F. This covers most of the southern and central United States.

Choose HS (12 or 24) if you regularly see temperatures below zero. Northern states, mountain regions, and anywhere with harsh winters.

Everything else between the MS and HS series is identical. Same build quality. Same 5-minute installation. Same guarantee. The HS just has that extra cold-weather capability built into the compressor.

Single Zone vs. Multi-Zone: One Unit or Many?

So you need to cool or heat multiple rooms. You have two options: buy multiple single-zone mini-splits, or buy one multi-zone system.

Option 1: Multiple Single-Zone Units

This means two (or more) completely independent systems. Each has its own outdoor unit and indoor unit.

The advantages:

• Redundancy. If one unit goes down, the other keeps running. You're never completely without climate control.
• True independence. You can run one zone in heating while another runs in cooling. Rare, but possible.
• Shorter line sets. Each outdoor unit can sit right outside the wall of its indoor unit. Less copper, less complexity.
• 110V power for the 12K units. You can plug them into a standard outlet.

Option 2: Multi-Zone Systems (MU24 or MU36)

This means one outdoor unit connected to multiple indoor units.

The advantages:

• One outdoor unit. Some people don't want two compressors sitting in their yard. Fair enough.
• Potentially lower cost. One outdoor unit is often cheaper than two, depending on configuration.
• Easier outdoor installation. You're only mounting one thing outside instead of two.

About BTU Sharing: Multi-splits share capacity between zones. The MU24 has 24,000 BTU total (with an 18K and 12K indoor unit). If both zones are demanding full power at the same time, the capacity gets divided. But in practice? You're usually only maxing out one zone at a time while the other maintains temperature. The system is smart about this.

MU24: Two Zones

Comes with one 18,000 BTU indoor unit and one 12,000 BTU indoor unit. Both connect to a single 24,000 BTU outdoor unit. Good for conditioning two separate spaces from one system.

MU36: Three Zones

Comes with three 12,000 BTU indoor units. All connect to a single 36,000 BTU outdoor unit. Ideal for a home where you want individual control in three different rooms.

Both multi-zone systems use the same Quick ’n’ Easy^TM connection method. Each zone takes about 5 minutes to hook up.

The Window Unit: When It Makes Sense

The WS12 is a different animal. It's a window-mounted unit, not a wall-mounted mini-split. And here's the important distinction: it's cooling only. No heat.

So why would you choose it?

The WS12 Is Perfect For:

• Renters. You can't put a hole in the wall, but you can put a unit in the window. And when you move, it comes with you.
• Temporary setups. Summer cabin. Seasonal workspace. Guest house you only use half the year.
• Maximum portability. Yes, our mini-splits are portable too. But there's still a hole in your wall when you remove them. The window unit just slides out.
• Budget-conscious cooling. It's our most affordable option for 12,000 BTU of solar-ready capacity.

The Trade-offs:

• Louder than a mini-split (55 dB vs. 42.5 dB).
• Lower efficiency (15 CEER, roughly equivalent to 17 SEER2).
• No heating. Summer use only, unless you have another heat source.

If you need year-round climate control, go with a mini-split. If you want easy, portable, solar-powered summer cooling, the WS12 is a solid choice.

Solar: Do You Need It Right Away?

Here's something that surprises people: you don't need solar panels to use an Airspool unit.

Every unit we sell works perfectly fine on grid power alone. The solar capability is built in and waiting for whenever you're ready. Plenty of our customers buy the unit first, use it on grid power, and add panels months or years later. Some never add panels at all.

Why buy a solar-hybrid unit if you're not going solar right away?

• The option is there. Energy costs only go one direction. Having solar-readiness built in means you're future-proofed.
• Insane efficiency even on grid. These units run 21-23 SEER2 for cooling. That's well above the federal minimum and better than most conventional systems.
• No conversion losses. When you do add solar, the DC power from your panels runs directly to the DC motors in the unit. No inverters. No batteries. No energy lost in translation.

Solar Panel Guidelines: When you're ready for panels, plan for about 1,500 watts per 12,000 BTU. So a 12K unit needs roughly 1,500W. A 24K unit needs around 3,000W. A 36K multi-split needs about 4,500W. These don't have to be exact. If you're a bit under, the grid fills in the gap. If you're over, no harm done.

We don't currently ship panels because they're big, heavy, and made of glass. But we'll help connect you with a local supplier. Budget roughly $600 for a 1,500W setup, or proportionally more for larger systems, plus mounting hardware.

Installation: Yes, You Can Actually Do This

This is where people get skeptical. "Sure, you say it's easy, but I've never done HVAC work in my life."

Neither have most of our customers. That's the whole point.

Traditional mini-split installation requires a vacuum pump, a nitrogen tank, a manifold gauge set, a torque wrench, refrigerant handling certification, and about 7 hours of skilled labor. There's a reason HVAC techs charge what they charge.

Airspool Quick ’n’ Easy^TM installation requires:

• A drill.

That's it. We provide everything else in the box: hole saw, drill bits, screwdriver bit, level, gloves, zip ties, insulation, electrical tape. All of it.

What The Installation Actually Looks Like:

1. Mount the indoor unit bracket on the wall. This takes the most time. You're drilling into your wall, mounting a bracket, maybe hitting a stud or two. Normal DIY stuff.

2. Drill a hole through the wall for the line set to pass through. We give you the hole saw.

3. Position the outdoor unit. Set it on a pad, mount it on a bracket, whatever works for your situation.

4. Connect everything. This is the 5-minute part:

   • Twist-to-connect the pre-charged refrigerant lines
   • Snap together the communication wire
   • Plug in the pre-installed power cord
   • Click in your solar lines (if using solar)

5. Turn it on.

Real Talk: We've had elderly customers install these units themselves. We've had people with zero mechanical experience figure it out in an afternoon. We have detailed installation videos. We have a comprehensive manual with dozens of photos, written in actual English by actual humans. And if you get stuck, our support team is a phone call or text away.

The mounting takes time. A couple hours, maybe, depending on your wall and your comfort level. But the actual connection? Five minutes. We timed it.

The Guarantee That Changes Everything

We get it. Buying HVAC equipment online feels weird. What if it doesn't work? What if you can't install it? What if it breaks in two years and you're stuck?

This is why we built the strongest guarantee in the industry.

Year One: Buy and Try

For the first 365 days, you can return your unit for any reason. Or no reason. Changed your mind? Send it back. Couldn't figure out the installation? Send it back. Just didn't love it? Send it back.

We pay for shipping both ways.

Read that again. You don't eat the freight cost if it doesn't work out. We do.

Years Two Through Five: Comfort That's Covered

Once you're past year one and happy with your unit (and you will be), we've got you covered for another four years. If something goes wrong:

• We'll help you troubleshoot.
• We'll send parts at our cost.
• We'll reimburse you for your time to install them.
• We'll cover all shipping.
• If we can't fix it, we'll replace the whole unit.

This isn't one of those warranties where they mail you a capacitor and wish you luck. We actually stand behind what we sell.

Are we crazy? Maybe. But not about this. We know these units are solid because we test every single one before it ships. Our return rate is remarkably low because the product actually works. We can afford to offer this guarantee because we rarely have to use it.

Every Airspool Unit at a Glance

MS12 — 12,000 BTU Standard ⭐ BEST SELLER

• Heats to 5°F
• Cools to 131°F
• 110V (standard outlet)
• Covers ~550 sq ft
• Needs ~1,500W solar

Best for: Most people. Single room, home office, garage, small apartment. Our most versatile and popular unit.

HS12 — 12,000 BTU Superheat

• Heats to -22°F
• Cools to 134°F
• 110V (20-amp)
• Covers ~550 sq ft
• Needs ~1,500W solar

Best for: Cold climate regions where winter regularly drops below zero.

MS24 — 24,000 BTU Standard

• Heats to 5°F
• Cools to 134°F
• 240V required
• Covers ~1,000 sq ft
• Needs ~3,300W solar

Best for: Larger single rooms, open floor plans, or small homes that need more power. Comes with kink-proof flexible line set.

HS24 — 24,000 BTU Superheat

• Heats to -22°F
• Cools to 134°F
• 240V required
• Covers ~1,000 sq ft
• Needs ~3,300W solar

Best for: Large spaces in cold climates. Kink-proof flexible line set included.

MU24 — 24,000 BTU Multi-Zone (2 indoor units)

• 18K + 12K indoor units
• Single outdoor unit
• 240V required
• 2 zones
• Needs ~3,000W solar

Best for: Two-room conditioning from one outdoor unit. Bedrooms, living room + bedroom, or any two-zone setup.

MU36 — 36,000 BTU Multi-Zone (3 indoor units)

• Three 12K indoor units
• Single outdoor unit
• 240V required
• 3 zones
• Needs ~4,500W solar

Best for: Three-room homes or larger spaces needing independent zone control from one system.

WS12 — 12,000 BTU Window Unit

• COOLING ONLY
• Window mount
• 110V (standard outlet)
• Covers ~550 sq ft
• Needs ~1,800W solar

Best for: Renters, temporary setups, seasonal use. Maximum portability. No wall penetration required.

The Bottom Line

If you're not sure where to start, start with the MS12. It handles most single-room applications, runs on a standard outlet, and costs the least. If you're in a cold climate, go with the HS12 instead. Need more power or multiple zones? Scale up from there.

Every Airspool unit ships with everything you need except a drill and the solar panels. Every unit is tested before it leaves our facility. Every unit is backed by a 5-year guarantee that actually means something.

We do the hard work at our Las Vegas factory so you don't have to figure it out in your backyard. The lines are pre-charged. The wires are pre-installed. The valves are ready to twist and seal. All you do is mount, connect, and enjoy.

This is real solar air conditioning. For real people. With real guarantees.

Questions? Text us at (725) 699-1200 or email comfort@airspool.com. We're actual humans and we actually respond.