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MRCOOL® HyperHeat®

MRCOOL DIY 12K Hyper Heat Ceiling Cassette Mini Split System – 23.5 SEER2, -22°F Heating, Pre-Charged Line Set

MRCOOL DIY 12K Hyper Heat Ceiling Cassette Mini Split System – 23.5 SEER2, -22°F Heating, Pre-Charged Line Set

SKUMC-HH12K-CASS12-25

TypeSingle Zone Mini Split System

Regular price $3,297.00
Sale price $3,297.00 Regular price $4,121.25
You Save: $824.25
SALE Sold out
Shipping calculated at checkout.

Refrigerant Type: R-454B

Line Set Length
In stock
Ready to ship
Free delivery*
Ships in 1–2 business days
Estimated arrival: Jul 10 – Jul 12
Based on order date & typical delivery times
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PRODUCT DESCRIPTION

MRCOOL DIY Hyper Heat 12K Ceiling Cassette Mini Split Bundle

The MRCOOL® DIY Hyper Heat 12K Ceiling Cassette Mini Split Bundle is a 5th Generation DIY ductless heat pump system designed for cold-climate heating and efficient cooling in spaces up to 550 sq. ft. This complete bundle includes the DIYHH-12-HP-C-230D25-O 12,000 BTU Hyper Heat outdoor condenser, the DIYCASSETTE12HP-230D25-O OuttaSight® one-way ceiling cassette, and a factory pre-charged DIY® QuickConnect® line set.

Built for real winter performance, this MRCOOL Hyper Heat system provides heating operation down to -22°F while delivering quiet, efficient cooling during warmer months. The ceiling cassette design keeps your walls open by installing between standard 16 in. ceiling joists, making it an excellent option for bedrooms, offices, additions, basements, garages, cabins, studios, and spaces where a wall-mounted air handler is not ideal.

The MRCOOL DIY system uses factory-sealed, pre-charged QuickConnect® technology with R-454B refrigerant. That means no vacuum pump, no gauges, no nitrogen, and no field refrigerant handling are required for the line set connection. Amazing, an HVAC system that does not immediately demand half a service van worth of tools.

What's Included

  • DIYHH-12-HP-C-230D25-O – 12K Hyper Heat Outdoor Condenser
  • DIYCASSETTE12HP-230D25-O – 12K OuttaSight® One-Way Ceiling Cassette
  • Pre-Charged DIY® QuickConnect® Line Set with R-454B Refrigerant
  • DIYPRO® Cable
  • Wireless Remote Control
  • SmartHVAC® WiFi Control Module
  • Installation Hardware
  • Mounting Template
  • Installation Manuals

Key Features

  • 12,000 BTU Hyper Heat heating and cooling performance
  • Designed for spaces up to 550 sq. ft.
  • Cold-climate heating operation down to -22°F
  • Flush-mount ceiling cassette design keeps walls open
  • Installs between standard 16 in. ceiling joists
  • Pre-charged DIY® QuickConnect® line set included
  • No vacuum pump, gauges, or refrigerant handling required
  • High-efficiency DC inverter compressor
  • Up to 23.5 SEER2 efficiency
  • 10 HSPF2-4 heating efficiency
  • Built-in condensate pump in the ceiling cassette
  • Quiet indoor operation from 24–41 dBA
  • SmartHVAC® App control for iOS and Android
  • Compatible with Amazon Alexa® and Google Assistant®
  • Gold Fin® anti-corrosion outdoor condenser coating

Ideal Applications

  • Bedrooms and guest rooms
  • Home offices and studios
  • Basements and finished lower levels
  • Bonus rooms and room additions
  • Garage conversions
  • Cabins and small homes
  • Tiny homes and ADUs
  • Airbnb and rental spaces
  • Workshops and hobby rooms
  • Rooms where a wall-mounted air handler is not preferred

Line Set Length Information

This system includes a standard 25 ft pre-charged QuickConnect® line set. Extended line set options may include an additional line set, couplers, and a longer control wire for installations requiring more distance between the indoor ceiling cassette and outdoor condenser.

QuickConnect® line sets should not be cut. Any extra line set length should be properly coiled and installed according to MRCOOL installation guidelines.

Performance Specifications

Specification Value
System Type 12K DIY Hyper Heat Ceiling Cassette Mini Split
Cooling Capacity 12,000 BTU
Heating Capacity 12,000 BTU
Recommended Coverage Area Up to 550 sq. ft.
SEER2 23.5
EER2 12.8
HSPF2-4 10
HSPF2-5 8
Heating Operating Range Down to -22°F
Operating Temperature Range -22°F to 122°F
Indoor Sound Level 24–41 dBA

Electrical & Refrigerant Specifications

Specification Value
Refrigerant Type R-454B, Factory Pre-Charged
Outdoor Unit Model DIYHH-12-HP-C-230D25-O
Outdoor Unit Voltage 208/230V, 1 Phase
Outdoor Minimum Circuit Ampacity 15A
Outdoor Maximum Fuse / Breaker 15A
Liquid Line Size 1/4 in.
Suction Line Size 3/8 in.
Indoor Unit Model DIYCASSETTE12HP-230D25-O
Indoor Unit Voltage 208/230V
Indoor Minimum Circuit Ampacity 3A
Indoor Maximum Fuse / Breaker 15A
Condensate Drain Integrated Condensate Pump

Outdoor Condenser Dimensions & Weight

Dimension Value
Outdoor Unit Width 31.69 in.
Outdoor Unit Height 21.81 in.
Outdoor Unit Depth 12.99 in.
Outdoor Unit Weight 72.31 lbs

Ceiling Cassette Dimensions & Mounting

Ceiling Cassette Specification Value
Indoor Unit Model DIYCASSETTE12HP-230D25-O
Ceiling Cassette Width 50.31 in.
Ceiling Cassette Height 8.98 in.
Ceiling Cassette Depth 13.19 in.
Ceiling Cassette Weight 45 lbs
Mounting Type Ceiling-Only Flush Mount
Joist Compatibility Fits Between 16 in. Ceiling Joists
Airflow Style One-Way Ceiling Cassette

Control Options

Control Feature Included
Wireless Remote Control Yes
SmartHVAC® App for iOS Yes
SmartHVAC® App for Android Yes
Amazon Alexa® Voice Control Yes
Google Assistant® Voice Control Yes
Programmable Timer Yes
Auto Mode Yes
Sleep Mode Yes
Dehumidification / Dry Mode Yes

Warranty Coverage

Warranty Item Coverage
Compressor Warranty 7-Year Compressor Warranty with Registration
Parts Warranty 5-Year Parts Warranty with Registration
Extended Coverage Limited Lifetime Compressor Replacement Available with MRCOOL® Care Enrollment

Frequently Asked Questions

Does this MRCOOL 12K ceiling cassette bundle include the line set?

Yes. This bundle includes a factory pre-charged DIY® QuickConnect® line set with R-454B refrigerant.

Do I need a vacuum pump or gauges to install this system?

No. The QuickConnect® line set is factory-sealed and pre-charged, so no vacuum pump, gauges, nitrogen, or field refrigerant handling are required for the line set connection.

Can the ceiling cassette be mounted on a wall?

No. The MRCOOL OuttaSight® cassette is designed as a ceiling-only indoor unit and should be installed between compatible ceiling joists.

Does the ceiling cassette have a condensate pump?

Yes. The ceiling cassette includes an integrated condensate pump, which gives more installation flexibility than a gravity-drain-only setup.

Can I install this MRCOOL DIY Hyper Heat system myself?

Yes. This MRCOOL DIY system is engineered for homeowner installation using QuickConnect® pre-charged line set technology. A qualified electrician is recommended for the required electrical connection.

What size space will this 12K ceiling cassette mini split cover?

This 12,000 BTU system is designed for spaces up to approximately 550 sq. ft. Actual sizing depends on insulation, ceiling height, window exposure, layout, climate zone, and other building conditions.

Will this system heat in below-freezing weather?

Yes. The MRCOOL DIY Hyper Heat 12K system is designed for cold-climate heating operation down to -22°F.

Why Buy From MRCOOL DIY Direct?

MRCOOL DIY Direct specializes in MRCOOL DIY systems, ceiling cassette bundles, line sets, accessories, parts, and support. Our team can help verify sizing, line set length, electrical requirements, and installation compatibility before you order.

A ceiling cassette system is a premium option, but only if the space, joist layout, and electrical setup make sense. We help make sure you get the right equipment the first time instead of discovering a compatibility issue while staring at a hole in the ceiling. Humanity has suffered enough.

Rated 4.7 / 5 Stars
4700+ Verified Reviews

Comfort That Speaks for Itself

See why homeowners and pros alike trust MRCOOL DIY systems to deliver comfort, savings, and easy installation.

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

Why Buy From Us

Why Buy from MRCOOL DIY Direct?

Trusted nationwide for MRCOOL DIY systems, support, and installation guidance.

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Top MRCOOL Dealer

Trusted nationwide for DIY mini split systems.

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DIY System Experts

Specializing in MRCOOL DIY systems and support.

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Fast Shipping

Quick delivery across the lower 48 states.

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Real Support

Help with sizing, compatibility, and installation.

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Family-Owned

Based in Missouri, serving nationwide.

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Complete System Guidance

We help you get everything needed for install.