New Season｜MRCOOL® DIY® 5th Gen 2-Zone 18,000 BTU Ductless Mini Split Air Conditioner & Heat Pump with (16ft+25ft) Pre-Charged Line Sets (6K+12K) air handlers R-454B — DIYM218HP

Description DIYM218HPW02D01
Take control of your comfort with the MRCOOL®DIY 5th Gen Multi-Zone Mini Split System - the easiest and most affordable way to get powerful, energy-saving heating and cooling without hiring a pro.

Two Rooms, Perfect Comfort: Heat or cool two spaces that are 200 sq. ft. and 550 sq. ft. each with independent temperature control for personalized comfort.

Truly DIY-Friendly: Forget expensive installs - no HVAC license or special tools required. If you can use basic hand tools, you can do this.

No Hassle Setup: Comes with 16ft + 25ft pre-charged Quick-Connect® line sets, so there’s no messy refrigerant handling or vacuuming. Just connect and enjoy.

Year-Round Savings: Boasting up to 23.9 SEER2 cooling efficiency and 10 HSPF2-4 heating performance, this system delivers serious energy savings.

Built for Every Season: Stay cozy even in the dead of winter - reliable heating works all the way down to -13°F. 100% at 5 degrees 

Strong Warranty Protection: Includes 7-Year Compressor Replacement and 5-Year Parts Coverage. Limited Lifetime Replacement Warranty with registration in the MRCOOL® Care Program

Whether it’s hot summer days or freezing winter nights, the MRCOOL® DIY®  Mini Split keeps your home comfortable and your energy bills low. Smart. Simple. Affordable.

What's Includes
• 1 18k BTU Condenser 
• 1 6K BTU Air Handler
• 1 12K BTU Air Handler
• 2 x DIY® Quick Connect® Pre-Charged Line Sets (16ftx25ft) 
Air Handler Compatibility
This condenser supports up to three indoor air handlers with a maximum combined capacity of 24,000 BTU. Available air handler sizes: 6K, 9K, and 12K BTU.
Examples of Compatible Combinations:

6K + 6K + 12K (24,000 BTU)
6K + 9K + 9K (24,000 BTU)
6K + 6K + 9K (21,000 BTU)
6K + 9K + 6K (21,000 BTU)
9K + 9K (18,000 BTU – one port unused)
6K + 12K (18,000 BTU – one port unused)

Recommended Wire Sizing

Recommended: 12 AWG copper wire – safe for 18A minimum circuit ampacity

One Size Smaller (14 AWG): Not recommended – may overheat under full load and violate electrical code

One Size Larger (10 AWG): Offers lower voltage drop and extra safety margin

Ideal Coverage Area
Perfect for spaces ranging from 750 to 1,100 sq. ft., depending on your climate zone and insulation quality.
SPECIFICATIONS & DIMENSIONS

SYSTEM OVERVIEW

System Type
Ductless Mini Split Air Conditioner & Heat Pump

Zones
2

Capacity
Total: 18,000 BTUZone 1: 6,000 BTUZone 2: 12,000 BTU

Coverage Area
Total: 650 sq. ft.Zone 1: 150 sq. ft.Zone 2: 500 sq. ft.

Refrigerant
R-454B

Line Sets Included
2 x Pre-Charged Line Sets

Warranty
7 Years Compressor5 Years Parts

 

OUTDOOR UNIT (18K) x 1

Model
DIY-MULTI3-18HP230D-O

Dimensions
35.04" W x 13.46" D x 26.50" H

Cooling Capacity
18,000 BTU

SEER2
23.9

EER2
13.0

Heating Capacity
18,000 BTU

HSPF2-4
10.0

HSPF2-5
7.8

Outdoor Noise Level
60.0 dB(A)

Outdoor Operating Temperature
Cooling: -13°F – 122°FHeating: -13°F – 75°F

Voltage
208–230V

Phase
1

Cycle
60Hz

Min Circuit Ampacity
16.0A

Max Fuse Breaker
20.0A

Weight
101.63 lbs

Certifications
ENERGY STAR CertifiedAHRI CertifiedUL ListedETL Listed

 

INDOOR UNIT (6K) x 1

Model
DIY-06-HP-WMAH-230D25-O

Dimensions
31.57" W x 7.44" D x 11.69" H

Mounting Type
Wall

Cooling Capacity
6,000 BTU

Heating Capacity
6,000 BTU

Coverage Area
100 to 150 sq. ft.

Liquid Line Size
1/4"

Suction Line Size
3/8"

Modes
Auto Mode: Automatically selects heating or cooling based on the room's temperature.Cool Mode: Lowers the room temperature to your desired setting.Heat Mode: Raises the room temperature to your desired setting.Fan-Only Mode: Circulates air without heating or cooling.Dry Mode (Dehumidification): Reduces humidity levels in the room.Sleep Mode: Gradually adjusts temperature settings for comfortable sleep and energy savings.

Weight
24.47 lbs

 

INDOOR UNIT (12K) x 1

Model
DIY-12-HP-WMAH-230D25-O

Dimensions
31.57" W x 7.44" D x 11.69" H

Mounting Type
Wall

Cooling Capacity
12,000 BTU

Heating Capacity
12,000 BTU

Coverage Area
351 to 500 sq. ft.

Liquid Line Size
1/4"

Suction Line Size
3/8"

Modes
Auto Mode: Automatically selects heating or cooling based on the room's temperature.Cool Mode: Lowers the room temperature to your desired setting.Heat Mode: Raises the room temperature to your desired setting.Fan-Only Mode: Circulates air without heating or cooling.Dry Mode (Dehumidification): Reduces humidity levels in the room.Sleep Mode: Gradually adjusts temperature settings for comfortable sleep and energy savings.

Weight
24.47 lbs

 
 
Frequently Asked Questions & Answers 
What's the difference between the 5th Gen and 4th Gen?
The 5th Gen MRCOOL DIY® Mini Split offers several key upgrades over the 4th Gen, focusing on efficiency, advanced technology, and eco-friendliness.
Here’s what’s new with the 5th Gen:

Next-Gen R-454B Refrigerant: A more environmentally friendly refrigerant with lower global warming potential (GWP), compliant with the latest HVAC regulations.

Higher Energy Efficiency: Improved SEER2 ratings for greater energy savings and optimized performance.

Enhanced System Reliability: Upgraded components for better heating and cooling performance.

Can I install it myself, or do I need a professional?
The MRCOOL DIY® system is designed for homeowners and doesn’t require HVAC tools. You can install the indoor and outdoor units yourself using the pre-charged Quick Connect® lines. However, a licensed electrician is required for the electrical hookup to ensure safety and code compliance.
Does it work in cold weather?
Yes. MRCOOL® 5th Gen systems feature low-ambient heating and can provide reliable heat even when outdoor temperatures drop to around 5°F.
How do I know what BTU size I need for my rooms?
A general rule of thumb is 20 BTU per square foot of space. Here's a rough guide:

6,000 BTU = 100 - 200sq ft
9,000 BTU = 150 - 400sq ft
12,000 BTU = 351- 550 sq ft
18,000 BTU = 501 – 800 sq ft
24,000 BTU = 751 – 1,050 sq ft
36,000 BTU = 1,001 - 1,550 sq ft

Some additional factors may impact performance such as insulation, ceiling height, sun exposure and the number of appliances in the room. For assistance, contact our Product Experts.

Does it heat as well as cool?Yes. All 5th Gen models are heat pumps, providing both heating and cooling for year-round comfort.

Is it Wi-Fi compatible?
Yes. The MRCOOL® SmartHVAC app allows smartphone control and works with Amazon Alexa and Google Assistant.
What is the warranty?

The MRCOOL® 5th Generation DIY Mini-Split systems offer the following warranty coverage:

7-Year Compressor Replacement Warranty: This warranty ensures that if the compressor fails within the first seven years, MRCOOL will provide a replacement.

5-Year Parts Warranty: This warranty covers all parts of the system for five years from the date of purchase.
eligible for the MRCOOL® Care Program enrollment

 
 
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