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MRCOOL DIY® 5th Gen Hyper Heat 18,000 BTU Single Zone Ceiling Cassette Mini Split System 230V, DIYHH-18-HP-CM-230D25

Brand: MRCOOL
Model: DIYHH-18-HP-CM-230D25
$3,682.00
$3,682.00 $4,998.00
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Mount type: Ceiling
In stock - Ready to Ship
Free Curbside Delivery
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!
Estimated Arrival: Dec 09 to Dec 15
$3,682.00
$3,682.00 $4,998.00

Product Overview

  • DIY Installation

  • Voltage: 208-230V

What's Included

  • MRCOOL DIY® 5th Gen Hyper Heat 18,000 BTU Single Zone Mini Split Condenser 230V, DIYHH-18-HP-C-230D25-O

    18K BTU Condenser

    Quantity: 1
  • 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

Can't find the right size?

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System Details

DESCRIPTION

Experience next-generation comfort with the MRCOOL® DIY® 18K BTU 208/230V Hyper Heat Single Zone Mini Split System, complete with the low-profile OuttaSight® Ceiling Cassette for a fully integrated, discreet climate solution. This high-performance system is designed for spaces up to 800 sq. ft., delivering reliable heating down to -22°F and efficient cooling up to 122°F for year-round comfort. The 25-foot No-Vac® QuickConnect® line set arrives pre-charged with eco-friendly R-454B refrigerant, eliminating the need for vacuum pumps or HVAC tools, while the DIYPRO® armored cable ensures long-term protection. The ceiling cassette installs flush within the ceiling for a seamless look and optimized airflow without occupying wall space. With smartphone app control, voice assistant compatibility, and MRCOOL’s industry-leading warranty protection, luxury comfort has never been more accessible for DIY homeowners.

  • Complete Ceiling Cassette System: Includes the 18K Hyper Heat outdoor condenser paired with the OuttaSight® Ceiling Cassette for a space-saving, flush-mounted air delivery solution.
  • Low-Profile Cassette Design: Installs discreetly within the ceiling, preserving room aesthetics while delivering even air distribution and exceptional comfort.
  • Hyper Heat Performance: Provides strong heating capability down to -22°F and steady cooling up to 122°F for dependable comfort in any climate.
  • DIY® Installation: The patented No-Vac® QuickConnect® line set comes pre-filled with R-454B refrigerant, enabling homeowner installation without special tools or gauges.
  • Room Size Coverage: Ideal for efficiently conditioning spaces between 500–800 sq. ft., including open-concept areas, basements, living rooms, and large bedrooms.
  • 360° Airflow Delivery: The ceiling cassette distributes air evenly throughout the room, reducing hot and cold spots and improving overall comfort.
  • Quiet, Efficient Operation: Designed for minimal noise with enhanced airflow engineering to maintain comfort without disrupting the environment.
  • Gold Fin® Protection: Corrosion-resistant outdoor condenser coating provides durability for both coastal and inland installations.
  • DIYPRO® Armored Cable: Protects crucial wiring from weather, pests, and exterior wear for long-term reliability.
  • Smart Control Compatibility: Adjust comfort using the included remote, the SmartHVAC app, or voice commands through Amazon Alexa and Google Assistant.
  • Energy-Saving Features: Includes Auto Mode, Sleep Mode, Turbo, Programmable Timer, and Follow Me® technology for personalized comfort with optimized energy use.
  • Auto Restart: Automatically resumes operation after a power interruption to maintain continuous comfort.
  • Premium Warranty Coverage: Includes a 7-year compressor and 5-year parts warranty, plus eligibility for limited lifetime compressor replacement through the MRCOOL® Care Program with registration and annual enrollment.

SPECIFICATIONS & DIMENSIONS

  • DIMENSIONS
  • Condenser Dimensions: 35.04" W x 13.46" D x 26.5" H
  • Condenser Weight: 99.87 lbs
  • Air Handler Dimensions: 50.31" W x 13.19" D x 8.98" H
  • Air Handler Weight: 45 lbs
  • CAPACITY & PEFORMANCE
  • Maximum Zones: 1
  • Cooling Capacity: 18,000 BTU
  • SEER2: 21.2
  • EER2: 12.5
  • Heating Capacity: 18,000 BTU
  • HSPF2-4: 11
  • HSPF2-5: 8.5
  • Outdoor Noise Level: 58 dB(A)
  • Outdoor Operating Temperature: Cooling: -5°F to 122°F//Heating: -22°F to 75°F
  • ELECTRICAL REQUIREMENTS
  • Voltage: 208-230V
  • Phase: 1
  • Cycle: 60 Hz
  • Max Fuse Breaker: 25A
  • Min Circuit Ampacity: 19A
  • REFRIGERANT & PIPING
  • Refrigerant Type: R-454B
  • Refrigerant Volume: 52.21 oz
  • Liquid Line Size: 1/4"
  • Suction Line Size: 1/2"
  • Max Line Set Length: 75 ft.
  • FEATURES
  • Coverage Area: 500 to 800 sq. ft.
  • Inverter: Yes
  • Compressor Motor Type: Rotary
  • Auto Mode: Yes
  • Wifi Compatibility: Yes
  • App Compatibility: Yes
  • Works with IOS: Yes
  • Works with Android: Yes
  • CERTIFICATIONS & WARRANTY
  • Certifications: Energy Star Certified, UL Listed, CSA Certified, ETL Certified, AHRI Certified
  • Warranty: 7 Years Compressor // 5 Years Parts

INSTALLATION & GUIDES

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Brochure PDF
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Installation Manual PDF
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Performance Specifications PDF
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Warranty PDF
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AHRI Certification PDF
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Energy Guide Certification 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.

BTU Coverage Guide

6,000 BTU
100-150 sq ft
9,000 BTU
151-350 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.

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