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Which 24,000 BTU MRCOOL mini split should I buy?
Short answer: A MRCOOL DIY 24K BTU mini split handles an open space of up to about 1,050 sq ft, like a combined kitchen, dining and living area. You can get it in DIY Select, DIY EasyPro or DIY 5th Gen, from $1,899, $2,109 and $3,329 (prices as of November 2026). For most buyers the EasyPro is the best value at 24K. The 5th Gen earns its price when you want the longest warranty or the line set run is long.
This is our 24K review for people who already know they need a big single zone unit and want to choose between the three. We'll cover the space it fits, the bigger line set, and the price gaps.
What space does a 24,000 BTU mini split cover?
At 20 to 25 BTU per square foot, 24,000 BTU covers about 960 to 1,200 sq ft with 8 ft ceilings. Our 5th Gen 24K listing puts the max at 1,050 sq ft, which is a fair limit for an average space.
Most 24K buyers have an open floor plan of 800 to 1,050 sq ft. An open kitchen and living area of 900 sq ft is a typical case: 900 times 22 is 19,800, plus about 4,000 for the kitchen, which comes to 23,800.
A 24K is the wrong tool for a house of separate rooms. It will hold the room it's in and do little for a bedroom down the hall with the door shut.
How do the three 24K units compare?
| 24K single zone | DIY Select | DIY EasyPro | DIY 5th Gen |
|---|---|---|---|
| Price | from $1,899 | from $2,109 | from $3,329 |
| SEER2 range for the line | 16.5 to 17.5 | 18.9 to 20.2 | 18.0 to 23.6 |
| ENERGY STAR at 24K | No | Yes, including Cold Climate | Check the ENERGY STAR listing |
| Heats down to | −13°F | −13°F | −13°F |
| Line set in the box | 11.5 ft | 11.5 ft | 25 ft |
| Leak detection, Follow Me, Gold Fin coil | No | Yes | Yes |
| DIYPro armored cable | No | No | Yes |
| Warranty, parts / compressor | 1 yr / 2 yr | 3 yr / 5 yr, lifetime option | 5 yr / 7 yr, lifetime option |
| Indoor unit color | White or black | White | White |
Exact SEER2 and HSPF2 for the 24K of each line are on the single zone specifications page. The lifetime compressor options need registration and MRCOOL's paid Care program.
DIY Select 24K: the lowest price, with real limits
The DIY Select is fine for a mild climate, a cabin you visit on weekends, or a space where a black indoor unit suits the wall. Skip it if this is the main system for a room you use every day in a hot or cold place.
At 24K, lower efficiency costs more in dollars than it does at 9K, because more energy flows through the unit. An example: at full output, 24,000 divided by a SEER2 of 17 is about 1,410 watts, and at a SEER2 of 22 it's about 1,090. Over 240 hours at an example rate of $0.17 per kWh, that 320 watt gap is about $13 a month.
DIY EasyPro 24K: our pick for most rooms
The DIY EasyPro costs $210 more than the Select. You get ENERGY STAR certification with the Cold Climate designation, leak detection, Follow Me, the Gold Fin coil coating and a 3 year parts warranty. For a living area in daily use, that's the best balance of price and features.
DIY 5th Gen 24K: the longest warranty and the longest line set
The DIY 5th Gen is $1,220 more than the EasyPro. That buys the highest efficiency ceiling of the three, DIYPro armored cable with no conduit, a 5 year parts and 7 year compressor warranty, and 25 ft of line set in the box. If you plan to stay in the house a long time and want the warranty, it's the one.
Next: How do I measure the line set length I need?
What line set does a 24K need?
The 24K uses the largest pipe in the single zone range, 3/8 x 5/8 in, the same as the 36K. Bigger pipe costs more and is stiffer to bend, so plan the route with gentle curves.
A run longer than 11.5 ft doesn't rule out the Select or EasyPro. A separate pre-charged line set in the matching pipe size extends them the same way it extends the 5th Gen, and the line set chart in your system's manual names the exact part. What changes is cost. A longer set in this pipe size adds a few hundred dollars, so on a 12 to 25 ft run the 5th Gen's included 25 ft trims some of its price gap.
Line sets are pre-charged and can't be cut; you coil the extra behind the outdoor unit. For long runs, a coupler kit for 24K and 36K is $455 and joins two sets for 66 or 75 ft. 75 ft is the max.
Watch how two pre-charged line sets join with the coupler before you decide whether your run needs one.
Where should a 24K indoor unit go in an open floor plan?
Mount it high on a long wall, near the middle of the space, so it blows across the room. A unit at the far end of a long room leaves the other end a few degrees off.
Avoid putting it right above the sofa or the dining table, where the airflow lands on people. Leave clear space in front of it, and follow the clearances in the installation manual for your size.
Should I get one 24K or two smaller units?
One 24K is the simplest and cheapest way to cover one open space: one outdoor unit, one line set, one hole in the wall.
Two units make sense when the space is an L or splits into areas you use at different times. Two single zone 12Ks run on 115V each, and two Select 12Ks come to about $2,798 against $1,899 for one Select 24K. A 5th Gen 2-room multi-zone, from $2,923, puts both indoor units on one outdoor unit with a setpoint for each.
The trade-off is cost and work: two indoor units means two holes and more wiring. If the space is a true open rectangle, one 24K is the better buy.
Next: When is a 36K single zone the better choice?
What does a 24K need for power and mounting?
All three 24K units run on 230V and need a dedicated circuit with a double-pole breaker. Breaker and wire sizes are in the installation manual for your size, and many towns require a licensed electrician for the panel work.
The outdoor unit is larger than the 9K to 18K units, so two people make mounting much easier. Set it on an equipment pad ($172) or a wall bracket, which is $147 in the 24K to 36K size. You'll also want a disconnect ($59) and a whip ($72), since no system includes them.
What if a 24K isn't quite right?
If the space is under about 750 sq ft with normal ceilings, an 18K will run longer cycles and handle humidity better. A space over about 1,200 sq ft, or around 1,000 with 10 ft ceilings, calls for the 36K, which only the 5th Gen offers.
All three 24K lines keep heating down to −13°F outside. If your winters drop below that, plan on a backup heat source or size up to the 36K, and call us for cold-climate sizing.
Ready to pick your 24K?
Confirm the space is roughly 800 to 1,050 sq ft and open enough for one indoor unit to reach. Measure the line set route along the wall, and price a longer 3/8 x 5/8 set into the Select or EasyPro if it's over 11.5 ft.
Then compare all three in our 24K single zone collection. If you're weighing one 24K against two smaller units, call +1 (844) 999-9725, Monday to Friday, 9 AM to 5 PM EST, with a rough floor plan, and we'll tell you which we'd choose.
