1. Home
  3. MRCOOL DIY 5th Generation Series

MRCOOL DIY 5th Gen 4-Zone 42,000 BTU Ceiling Cassette Ductless Mini Split Air Conditioner & Heat Pump with Pre-Charged Line Sets (6K+9K+9K+18K), DIYM455HP

Brand: MRCOOL
Model: DIYM455HPC03D00
$10,301.00
$10,301.00 $13,185.28
You save $2,884.28
Shipping calculated at checkout.

Payment Plans Available

16 ft. + 16 ft. + 16 ft. + 16 ft.
16 ft. + 16 ft. + 16 ft. + 16 ft.
25 ft. + 25 ft. + 25 ft. + 25 ft.
35 ft. + 35 ft. + 35 ft. + 35 ft.
50 ft. + 50 ft. + 50 ft. + 50 ft.

Need different line set lengths?
Configure your system here!
In Stock
Delivers Jul 27-Aug 2 (Est.)
Free Curbside Shipping
Curbside shipping means your order will be delivered to the curb or driveway outside your home. The driver will not bring it inside or set it up. Please arrange for help if needed!
$10,301.00
$10,301.00 $13,185.28
Ask about this product Get an answer with HVAC AI™
AI-generated from product data and store information. Responses may not always be accurate. For any clarifications, talk to our team.

What's Included

  • MRCOOL DIY® 5th Gen 55,000 BTU Multi-Zone Mini Split Condenser 230V, DIY-MULTI6-55HP230D-O

    55K BTU Condenser

    Quantity: 1
    In Stock Delivers Jul 27-Aug 2 (Est.)
  • MRCOOL DIY® 5th Gen 6,000 BTU Multi-Zone Mini Split Ceiling Cassette Air Handler 230V, DIYCASSETTE06HP-230C25-O

    6K BTU Air Handler

    Quantity: 1
    In Stock Delivers Jul 27-Aug 2 (Est.)
  • MRCOOL DIY® 5th Gen 9,000 BTU Multi-Zone Mini Split Ceiling Cassette Air Handler 230V, DIYCASSETTE09HP-230C25-O

    9K BTU Air Handler

    Quantity: 2
    In Stock Delivers Jul 27-Aug 2 (Est.)
  • MRCOOL DIY® 5th Gen 18,000 BTU Multi-Zone Mini Split Ceiling Cassette Air Handler 230V, DIYCASSETTE18HP-230C25-O

    18K BTU Air Handler

    Quantity: 1
    In Stock Delivers Jul 27-Aug 2 (Est.)
  • MRCOOL DIY® 5th Gen 16 ft. 1/4" x 1/2" Pre-Charged Quick Connect Line Set - R454B (for 18K Indoor Units)

    Pre-Charged Line Set

    Quantity: 4
    In Stock Delivers Jul 27-Aug 2 (Est.)

Complete Your System

System Details

DESCRIPTION

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.

  • Four Rooms, Perfect Comfort: Heat or cool four spaces that are 150 sq. ft., 350 sq. ft., 350 sq. ft. and 750 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 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 22.0 SEER2 cooling efficiency and 10.6 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.
  • Strong Warranty Protection: Includes 7-Year Compressor Replacement and 5-Year Parts Coverage.

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.

SPECIFICATIONS & DIMENSIONS

  • SYSTEM OVERVIEW
  • System Type: Ductless Mini Split Air Conditioner & Heat Pump
  • Zones: 4
  • Capacity: Total: 42,000 BTU//Zone 1: 6,000 BTU//Zone 2: 9,000 BTU//Zone 3: 9,000 BTU//Zone 4: 18,000 BTU
  • Coverage Area: Total: 1,600 sq. ft.//Zone 1: 150 sq. ft.//Zone 2: 350 sq. ft.//Zone 3: 350 sq. ft.//Zone 4: 750 sq. ft.
  • Refrigerant: R-454B
  • Line Sets Included: 4 x Pre-Charged Line Sets
  • Warranty: 7 Years Compressor//5 Years Parts
  • OUTDOOR UNIT (55K) x 1
  • Model: DIY-MULTI6-55HP230D-O
  • Dimensions: 37.48" W x 16.34" D x 52.48" H
  • Cooling Capacity: 47,000 BTU
  • SEER2: 22.0
  • EER2: 12.0
  • Heating Capacity: 55,000 BTU
  • HSPF2-4: 10.6
  • HSPF2-5: 8.5
  • Outdoor Noise Level: 64.0 dB(A)
  • Outdoor Operating Temperature: Cooling: 5°F – 122°F//Heating: -13°F – 75°F
  • Voltage: 208–230V
  • Phase: 1
  • Cycle: 60Hz
  • Min Circuit Ampacity: 43.0A
  • Max Fuse Breaker: 45.0A
  • Weight: 245.81 lbs
  • Certifications: ENERGY STAR Certified//AHRI Certified//UL Listed//ETL Listed
  • INDOOR UNIT (6K) x {Insert Number}
  • Model: DIYCASSETTE06HP-230D25-O
  • Dimensions: 50.31" W x 13.19" D x 8.98" H
  • Mounting Type: Ceiling
  • 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"
  • Airflow Direction: 1-Way
  • 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: 45 lbs
  • INDOOR UNIT (9K) x {Insert Number}
  • Model: DIYCASSETTE09HP-230D25-O
  • Dimensions: 50.31" W x 13.19" D x 8.98" H
  • Mounting Type: Ceiling
  • Cooling Capacity: 9,000 BTU
  • Heating Capacity: 9,000 BTU
  • Coverage Area: 151 to 350 sq. ft.
  • Liquid Line Size: 1/4"
  • Suction Line Size: 3/8"
  • Airflow Direction: 1-Way
  • 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: 45 lbs
  • INDOOR UNIT (9K) x {Insert Number}
  • Model: DIYCASSETTE09HP-230D25-O
  • Dimensions: 50.31" W x 13.19" D x 8.98" H
  • Mounting Type: Ceiling
  • Cooling Capacity: 9,000 BTU
  • Heating Capacity: 9,000 BTU
  • Coverage Area: 151 to 350 sq. ft.
  • Liquid Line Size: 1/4"
  • Suction Line Size: 3/8"
  • Airflow Direction: 1-Way
  • 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: 45 lbs
  • INDOOR UNIT (18K) x {Insert Number}
  • Model: DIYCASSETTE18HP-230D25-O
  • Dimensions: 50.31" W x 13.19" D x 8.98" H
  • Mounting Type: Ceiling
  • Cooling Capacity: 18,000 BTU
  • Heating Capacity: 18,000 BTU
  • Coverage Area: 501 to 750 sq. ft.
  • Liquid Line Size: 1/4"
  • Suction Line Size: 1/2"
  • Airflow Direction: 1-Way
  • 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: 45 lbs

INSTALLATION & GUIDES

File icon
Installation Manual PDF
File icon
5th Gen Brochure PDF
File icon
Energy Guide PDF
File icon
AHRI Certificate PDF
File icon
Remote Control Manual PDF
File icon
Warranty PDF

SHIPPING POLICY

Free Curbside Delivery
MRCOOL orders include free curbside delivery via FedEx Ground, FedEx Freight, or the most trusted carrier available. Please note that delivery is to the curbside only - be sure to arrange for assistance if needed, as the carrier will not bring items inside your home.

Tracking & Delivery Scheduling
In most cases, you will receive tracking details 3-5 business days after you place your order. When the tracking number is sent, please allow 1-2 business days for the tracking number to populate details.

See our full Shipping Policy here.

RETURN POLICY

MRCOOL returns must be requested within 30 days of your delivery date. We are unable to process returns submitted after this period. Products must be unused, uninstalled, and in their original packaging, including the box and pallet, to qualify for a return.

Restocking Fee
Please note, a 35% restocking fee will be applied to all approved returns.

Non-Returnable Items
Accessories including lineguards, wall mounts, linesets, couplers, and similar items are not eligible for return.

See our full Return Policy here.

Frequently Asked Questions

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.

For a full breakdown, check out our blog.

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 - 150 sq ft
  • 9,000 BTU = 150 - 350 sq ft
  • 12,000 BTU = 351- 500 sq ft
  • 18,000 BTU = 501 – 750 sq ft
  • 24,000 BTU = 751 – 1,000 sq ft
  • 36,000 BTU = 1,001 - 1,500 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.

View Warranty Document here.

See more from MRCOOL