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Home 24,000 BTU MRCOOL DIY Series
MRCOOL DIY Series

MRCOOL® DIY 18K Hyper Heat Complete Mini-Split System – 5th Gen Wall Mount (230V) DIYHH-18-HP-C-230D25-O + DIY-18-HP-WMAH-230D25-O

SKU DIYHH-18-HP-C-230D25-O + DIY-18-HP-WMAH-230D25-O Wall Mount208-230V
$3,173.00
In StockShips in 1-2 business days
High efficiency. Quiet performance. Easy installation.

A smart, reliable choice for year-round comfort.

Best for 9K-18K room setups:
  • Bedrooms
  • Home offices
  • Sunrooms
  • Small living rooms
24,000 BTU
Cooling
24,000 BTU
Heating
See specs
Quiet Inside
See specs
High Efficiency

Brand Information

MrCool
Support Number
(270)366-0457
Product Overview Full product description Read the longer product copy, features, and application notes.

MRCOOL® DIY 18K Hyper Heat 5th Gen Mini Split System


Summary

The MRCOOL® DIYHH-18 Hyper Heat 18K Mini Split Systemis a 2025 5th Generation innovation engineered for true cold-climate performance down to -22°F with genuine DIY installation. This complete bundle delivers powerful 18,000 BTU heating and cooling for spaces up to 800 sq. ft., combining professional HVAC capability with homeowner-friendly setup.

Featuring the advanced DIYHH-18-HP-C-230D25-O outdoor condenser and DIY-18-HP-WMAH-230D25-O wall-mounted air handler, this system utilizes factory-sealed QuickConnect® pre-charged line sets with R-454B refrigerant—eliminating the need for vacuum pumps, gauges, or HVAC certification. With high efficiency ratings of 21.2 SEER2 and 11 HSPF2-4, smart controls via the MRCOOL SmartHVAC App, and compatibility with Alexa and Google Assistant, this system offers premium, reliable comfort for garages, additions, workshops, and whole-room applications.


What's Included

  • Outdoor Condenser (MRCOOL® DIYHH-18 Hyper Heat Condenser - DIYHH-18-HP-C-230D25-O)
  • Wall-Mounted Air Handler (MRCOOL® DIY-18 Wall Mount Air Handler - DIY-18-HP-WMAH-230D25-O)
  • 25 ft Pre-Charged QuickConnect® Line Set (DIY25-1412)
  • DIYPRO® Communication Cable
  • Wireless Remote Control
  • Complete Mounting Hardware & Template
  • Installation and User Manuals

Warranty

  • 7-Year Compressor Warranty (Registration Required)
  • 5-Year Parts Warranty (Registration Required)
  • Extended Limited Coverage with MRCOOL® Care

Important:Warranty benefits require product registration. Refer to MRCOOL's official warranty documentation for full terms and conditions.


Technical Information

Model Number:DIYHH-18-HP-C-230D25-O(MRCOOL® DIYHH-18 Hyper Heat Outdoor Condenser)

BRAND NAME

MRCOOL

SERIES

DIY Hyper Heat 5th Gen

MODEL

DIYHH-18-HP-C-230D25-O

UNIT TYPE

Mini-Split

EQUIPMENT TYPE

Condenser

SHORT DESCRIPTION

18K Hyper Heat 230V Condenser with QuickConnect®

COOLING CAPACITY (BTU)

18,000

HEATING CAPACITY (BTU)

18,000

SEER2

21.2

EER2

12.5

HSPF2-4

11

HSPF2-5

8.5

VOLTAGE (V)

208/230

PHASE

1

CYCLE

60 Hz

MIN CIRCUIT AMPACITY (A)

19

MAX FUSE BREAKER (A)

25

MIN AMBIENT HEAT (F)

-22°F

MAX AMBIENT COOL (F)

122°F

CFM

1765.8

COMPRESSOR TYPE

Inverter Rotary

REFRIGERANT TYPE

R-454B

REFRIGERANT VOLUME (OZ)

52.21 oz

METERING DEVICE

Electronic Expansion Valve (EEV)

LINE SET INCLUDED

Yes

LINE SET LENGTH

25 ft

MAX LINESET LENGTH (FT)

75 ft

LIQUID LINE SIZE

1/4"

SUCTION LINE SIZE

1/2"

DECIBEL RATING HIGH (DBA)

58

NET WIDTH (IN)

35.04

NET HEIGHT (IN)

26.5

NET DEPTH (IN)

13.46

NET WEIGHT (LBS)

99.87

Model Number:DIY-18-HP-WMAH-230D25-O(MRCOOL® DIY-18 Wall-Mount Air Handler)

BRAND NAME

MRCOOL

SERIES

DIY 5th Gen

MODEL

DIY-18-HP-WMAH-230D25-O

UNIT TYPE

Mini-Split

EQUIPMENT TYPE

Air Handler

SHORT DESCRIPTION

18K 230V Wall Mount Air Handler

COOLING CAPACITY (BTU)

18,000

HEATING CAPACITY (BTU)

18,000

MAX COVERAGE AREA

800 sq. ft.

MOUNT TYPE

Wall

FAN SPEEDS

5-Speed

QUIET MODE

Yes

DECIBEL RATING LOW (DBA)

19

DECIBEL RATING HIGH (DBA)

54.5

NET WIDTH (IN)

42.52

NET HEIGHT (IN)

13.19

NET DEPTH (IN)

8.9

NET WEIGHT (LBS)

35.49

SMART FEATURES

MRCOOL SmartHVAC App, Alexa, Google Assistant, Wireless Remote

System Highlights

  • 2025 5th Generation Hyper Heat:Newest model with enhanced cold-climate performance down to -22°F.
  • True DIY Installation:Pre-charged QuickConnect® line set requires no special HVAC tools or certification.
  • High-Capacity 18K BTU:Ideal for spaces up to 800 sq. ft. including large rooms, garages, and workshops.
  • Premium Efficiency:21.2 SEER2 and 11 HSPF2-4 ratings for superior energy savings.
  • Smart Connectivity:Full control via MRCOOL SmartHVAC App, voice commands (Alexa/Google Assistant), and included remote.
  • Quiet Operation:Indoor unit operates as low as 19 dB for undisturbed comfort.
  • Complete Bundle:Everything included for a single-zone installation—just add electrical connection.
  • Robust Warranty:Industry-leading 7-year compressor and 5-year parts warranty with registration.

Frequently Asked Questions

Q: Is this system really DIY-friendly?
A: Yes. The pre-charged, factory-sealed QuickConnect® line set eliminates the most complex steps of traditional mini-split installation. No vacuum pump, gauges, or refrigerant handling is required.

Q: How low of a temperature can it heat?
A: This Hyper Heat system is engineered to provide effective heating down to -22°F outdoor temperature.

Q: What electrical requirements are needed?
A: A dedicated 208/230V circuit with a 25A breaker is required (19A minimum circuit ampacity).

Q: Is the line set included?
A: Yes, a 25-foot pre-charged QuickConnect® line set is included. Extended lengths are available as options.

Q: Does it come with smart controls?
A: Yes. The system includes WiFi capability for the MRCOOL SmartHVAC App and is compatible with Amazon Alexa and Google Assistant for voice control.

Specs & Documents Product details Open technical specs, manuals, videos, and product documents.

Technical Data

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Product FAQs

Product FAQs

Helpful answers matched to this product, brand, specs, and configuration.
Where should I purchase MRCOOL equipment?

MRCOOL products are sold through authorized retailers and distributors rather than directly by MRCOOL to consumers. Purchasing through an authorized seller helps confirm that the equipment is genuine and that the correct purchase records are available for product and warranty support.

Can MRCOOL components from different series, generations, or refrigerant platforms be mixed?

Do not assume that MRCOOL indoor units, outdoor units, line sets, controls, or accessories are interchangeable. Use only manufacturer-approved combinations for the exact model family; in particular, MRCOOL states that R-410A products are not compatible with R-454B products and the refrigerants must never be mixed.

What makes an eligible MRCOOL DIY system different from a conventional mini-split?

Eligible MRCOOL DIY systems are designed around installation-friendly components such as factory-precharged line sets and compatible connection hardware. The included components vary by generation and package, and electrical work, permits, clearances, and local code requirements still need to be followed.

Does MRCOOL send technicians to a home or jobsite?

MRCOOL does not dispatch field technicians. Its in-house team provides phone and email assistance for diagnosis, troubleshooting, and product guidance, while the owner arranges and pays for any local on-site technician unless a specific written warranty program states otherwise.

Why do I need the exact MRCOOL model and serial number?

The model and serial number identify the exact equipment, generation, capacity, and applicable documentation or warranty. Use the identification labels on the equipment and MRCOOL’s registration guidance rather than relying only on a product title or general series name.

Are all MRCOOL systems designed for do-it-yourself installation?

No. Only product families specifically identified by MRCOOL as DIY-capable should be treated as do-it-yourself systems. Other lines, including the Advantage Series, require professional HVAC installation, so always follow the installation requirements for the exact model.

Where can I find MRCOOL manuals, specifications, certifications, and installation documents?

MRCOOL maintains a documentation library and a product support center with model-specific installation manuals, owner manuals, technical documents, certifications, warranty information, and troubleshooting resources. Search using the exact model number because documents can differ by series, generation, capacity, and refrigerant.

What types of products does MRCOOL offer?

MRCOOL offers a broad range of comfort products, including ductless mini-splits, central ducted split systems, packaged heat pumps, geothermal systems, water heaters, fans, thermostats, line sets, and HVAC accessories. Available capacities, refrigerants, efficiencies, and features depend on the exact product family and model.

When should an MRCOOL system be registered?

Register the system as soon as possible after purchase and installation. Several MRCOOL residential warranty programs require registration within 60 days of installation, or within 60 days of purchase when the installation date cannot be verified, but the exact requirement is controlled by the warranty document for the specific product.

Where can I purchase replacement parts for an MRCOOL system?

MRCOOL recommends starting with the original place of purchase because many dealers can special-order replacement parts. If that is not available, use an authorized MRCOOL parts distributor and confirm compatibility with the exact model and serial number before ordering.

How can I contact MRCOOL customer or technical support?

MRCOOL provides support by phone at (270) 366-0457, by email at support@mrcool.com, and through its online support-request form. Have the exact model and serial number available so the support team can identify the correct product documentation and next steps.

Can MRCOOL support work with my local HVAC technician?

Yes. If a local technician is scheduled, MRCOOL’s in-house support team can help coordinate troubleshooting and product guidance with that technician. The technician should have the model, serial number, system configuration, measurements, error codes, and a clear description of the issue available.

Where can I find MRCOOL troubleshooting and error-code information?

MRCOOL’s support center provides separate technical-support sections for ductless systems, residential ducted systems, product-specific error codes, wiring guidance, installation procedures, and troubleshooting articles. Use the exact series and model because codes and procedures are not universal across all MRCOOL equipment.

How do I register an MRCOOL product for warranty coverage?

Register the product through MRCOOL’s online warranty-registration page. Be prepared to provide the serial number along with purchase, owner, installation-location, and installer information requested by the registration form.

Does every MRCOOL product have the same warranty?

No. MRCOOL publishes separate warranty terms for different product families, generations, and applications. For example, the current DIY 5th Generation warranty lists 5-year parts and 7-year compressor coverage, but that coverage should not be assumed for another MRCOOL series; always check the exact product warranty document.

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