MRCOOL DIY 5th Gen — Multi-Zone Mini Split Heat Pump System (One-Way Ceiling Cassettes)
MRCOOL DIY 5th Gen 3-Zone Ductless Mini Split AC & Heat Pump 27000 BTU (6K+6K+18K), One-Way Cassette Units, 230V
A multi-zone heating & cooling system designed for DIY setup, smart control, and a clean ceiling look with one-way cassette air handlers.
Overview
27000 BTU
3 Zones
23 SEER2
Heats to -13°F
R-454B
One-Way Ceiling Cassettes
Smart App Control
Alexa & Google
Enjoy room-by-room comfort with low-profile one-way ceiling cassettes that deliver directional airflow and a finished, built-in appearance. Each zone is independently controlled for comfort where you need it—without wasting energy where you don’t.
System Combination
DIY-MULTI4-27HP230D-O + 2X DIYCASSETTE06HP-230D25-O + DIYCASSETTE18HP-230D25-O
DIY-MULTI4-27HP230D-O + 2X DIYCASSETTE06HP-230D25-O + DIYCASSETTE18HP-230D25-O
Outdoor Model
DIY-MULTI4-27HP230D-O
DIY-MULTI4-27HP230D-O
Min Circuit Ampacity
23
23
Max Fuse / Breaker
25
25
Why Homeowners Love It
- Cleaner look: One-way ceiling cassettes sit flush and keep walls free for furniture, art, and windows.
- DIY-friendly setup: Designed to reduce install complexity and avoid specialized HVAC steps when using DIY Quick Connect line sets.
- Whole-home zoning: Set different temperatures in different rooms for more comfort and less wasted energy.
- Smart control: Manage each zone with app control and voice assistants.
- All-season comfort: Cooling, heating, dry/dehumidify, and auto modes for changing weather.
- Built to last: Gold Fin condenser coating helps resist corrosion in harsh climates.
What’s Included
- (1) Outdoor condenser: DIY-MULTI4-27HP230D-O
- Indoor units (one-way ceiling cassettes):
- 6,000 BTU (x2) — Model: DIYCASSETTE06HP-230D25-O
- 18,000 BTU (x1) — Model: DIYCASSETTE18HP-230D25-O
- Wireless remotes (zone control)
- DIY Quick Connect line sets (installation kit must be selected to be included; DIY Quick Connect line sets are the pre-charged component)
- Manuals & documentation (see Documents & Downloads)
MRCOOL DIY — How It Works
Key Features
- One-way cassette airflow: Directional discharge helps spread comfort across the room with a streamlined ceiling look.
- DIY Quick Connect compatibility: Pre-charged line sets (when included/selected) can eliminate vacuum pump and gauge steps.
- Energy-efficient inverter performance for stable temperatures and lower operating costs.
- Gold Fin condenser for corrosion resistance and durability.
- Quiet comfort: Smooth DC inverter operation with adjustable fan speeds and comfort-focused modes.
- Smart control options: App control + voice assistants + remote control for each zone.
- Low-ambient performance with heating capability down to -13°F.
DIY Quick Connect line sets are model-specific and must match the system. Always follow the installation manual for your exact configuration.
Comfort Modes
- Auto: Automatically selects heating or cooling to maintain setpoint.
- Cool / Heat: Dedicated modes for seasonal comfort.
- Dry: Dehumidifies while maintaining comfort.
- Sleep: Energy-saving overnight profile.
- Timer: Scheduled on/off for efficiency.
Warranty
Coverage commonly includes a 7-year compressor warranty and a 5-year parts warranty (registration requirements apply).
Optional lifetime compressor coverage may be available depending on program/registration.
Indoor Specs
Indoor Unit Specifications — DIYCASSETTE06HP-230D25-O
| brand name | MRCOOL |
|---|---|
| sku | DIY 5th Gen OuttaSight |
| model | DIYCASSETTE06HP-230D25-O |
| unit type | Mini-Split |
| short description | MRCOOL® DIY® Series 5th Gen OuttaSight® 6K BTU 230V One-Way Ceiling Cassette |
| works with | DIY 5th Gen Systems |
| feature list |
|
| cfm | 341 / 294 / 259 / 235 / 235 |
| voltage (V) | 208-230 |
| phase | 1 |
| cycle (Hz) | 60 |
| max fuse breaker (a) | 15 |
| min circuit ampacity (a) | 3 |
| mount type | Ceiling |
| color | White |
| rated load | 0.8 |
| max coverage area | 200 |
| refrigerant type | R-454B |
| decibel rating (dba) | 35.5 |
| decibel rating low (dba) | 23.5 |
| decibel rating high (dba) | 46.5 |
| air flow direction | 1-Way |
| liquid line size | 1/4 |
| suction line size | 3/8 |
| blower motor rpm | 1024/944/784 |
| filter type | Reusable |
| fan only option | Yes |
| quiet mode | Yes |
| sleep mode | Yes |
| auto cool | Yes |
| wifi compatibility | Yes |
| app compatibility | Yes |
| works with ios | Yes |
| works with android | Yes |
| remote control included | Yes |
| registered warranty | Limited Lifetime Compressor |
| base warranty | 5-Year Part/7-Year Compressor |
| base parts warranty | 5 Years |
| registered compressor warranty | Limited Lifetime Compressor |
| base compressor warranty | 7 Years |
| has batteries | Yes |
| contains electronics | Yes |
| contains chemicals | Yes |
| contains aerosol | Yes |
| contains compressed gas | Yes |
| proposition 65 warning | Yes |
| restricted states | GU;PR;VI |
| net depth (in) | 13.19 |
| net height (in) | 8.98 |
| net width (in) | 50.31 |
| net weight | 45 |
| gross depth (in) | 22.48 |
| gross height (in) | 22.64 |
| gross width (in) | 57.6 |
| gross weight (lbs) | 88 |
Indoor Unit Specifications — DIYCASSETTE18HP-230D25-O
| brand name | MRCOOL |
|---|---|
| sku | DIY 5th Gen OuttaSight |
| model | DIYCASSETTE18HP-230D25-O |
| unit type | Mini-Split |
| short description | MRCOOL® DIY® Series 5th Gen OuttaSight® 18K BTU 230V One-Way Ceiling Cassette |
| works with | DIY 5th Gen Systems |
| feature list |
|
| cfm | 400 / 352 / 300 / 207 / 207 |
| cooling capacity (BTU) | 18800 |
| heating capacity (BTU) | 22700 |
| voltage (V) | 208-230 |
| phase | 1 |
| cycle (Hz) | 60 |
| max fuse breaker (a) | 15 |
| min circuit ampacity (a) | 3 |
| mount type | Ceiling |
| color | White |
| rated load | 1.2 |
| max coverage area | 800 |
| refrigerant type | R-454B |
| decibel rating (dba) | 41.5 |
| decibel rating low (dba) | 26 |
| decibel rating high (dba) | 44 |
| air flow direction | 1-Way |
| liquid line size | 1/4 |
| suction line size | 1/2 |
| blower motor rpm | 1344/1184/1024 |
| filter type | Reusable |
| fan only option | Yes |
| quiet mode | Yes |
| sleep mode | Yes |
| auto cool | Yes |
| wifi compatibility | Yes |
| app compatibility | Yes |
| works with ios | Yes |
| works with android | Yes |
| remote control included | Yes |
| registered warranty | Limited Lifetime Compressor |
| base warranty | 5-Year Part/7-Year Compressor |
| base parts warranty | 5 Years |
| registered compressor warranty | Limited Lifetime Compressor |
| base compressor warranty | 7 Years |
| has batteries | Yes |
| contains electronics | Yes |
| contains chemicals | Yes |
| contains aerosol | Yes |
| contains compressed gas | Yes |
| proposition 65 warning | Yes |
| restricted states | GU;PR;VI |
| net depth (in) | 13.19 |
| net height (in) | 8.98 |
| net width (in) | 50.31 |
| net weight | 45 |
| gross depth (in) | 22.48 |
| gross height (in) | 22.64 |
| gross width (in) | 57.6 |
| gross weight (lbs) | 88 |
Manuals
- https://doxrepo.mrcool.com/mc-diy-5-cass-im-um-en-01.pdf
- https://doxrepo.mrcool.com/mc-5-diy-oly-cass-rmt-im-um-en-01.pdf
- https://doxrepo.mrcool.com/mc-diy-5-cass-sm-en-01.pdf
Documents
Warranty
Outdoor Specs
Outdoor Unit Specifications — DIY-MULTI4-27HP230D-O
| brand name | MRCOOL |
|---|---|
| sku | DIY 5th gen Multi-Zone Mini-splits |
| model | DIY-MULTI4-27HP230D-O |
| short description | MRCOOL® 27k DIY 5th Generation 4 Zone Multi-Zone Mini-Split Condenser 230v |
| feature list |
|
| seer2 | 23 |
| eer2 | 12 |
| hspf2-4 | 9.5 |
| hspf2-5 | 7 |
| tonnage | 2.25 |
| cooling capacity (BTU) | 26000 |
| heating capacity (BTU) | 26000 |
| voltage (V) | 208/230 |
| phase | 1 |
| cycle (Hz) | 60 |
| max fuse breaker (a) | 25 |
| min circuit ampacity (a) | 23 |
| color | White |
| zone capacity | 4 |
| refrigerant type | R-454B |
| refrigerant volume (oz) | 84.66 |
| decibel rating (dba) | 61 |
| inverter | DC |
| line set length | 25 |
| max lineset length (ft) | 221.4 |
| compressor motor type | Rotary |
| auxiliary heater included | No |
| auxiliary heater available | No |
| fan only option | Yes |
| quiet mode | Yes |
| auto cool | Yes |
| wifi compatibility | Yes |
| app compatibility | Yes |
| works with ios | Yes |
| works with android | Yes |
| ul listed | Yes |
| etl listed | Yes |
| energy star certified | Yes |
| ahri certified | Yes |
| registered warranty | Extended Limited Lifetime* |
| base parts warranty | 5 |
| base compressor warranty | 7 |
| has batteries | Yes |
| contains electronics | Yes |
| contains chemicals | Yes |
| contains aerosol | Yes |
| contains compressed gas | Yes |
| proposition 65 warning | Yes |
| net depth (in) | 16.14 |
| net height (in) | 31.89 |
| net width (in) | 37.24 |
| net weight | 140.21 |
| gross depth (in) | 19.69 |
| gross height (in) | 34.84 |
| gross width (in) | 42.91 |
| gross weight (lbs) | 151.02 |
Manuals
- https://doxrepo.mrcool.com/mc-diy-5-mz-im-um-en-01.pdf
- https://doxrepo.mrcool.com/mc-ms-5-rm-en-01.pdf
Documents
- https://doxrepo.mrcool.com/mc-mz-diy-5-br-en-01.pdf
- https://doxrepo.mrcool.com/mc-s-kit-um-en-fr-01.pdf
Warranty
Helpful Notes
Mixing indoor unit types
Many multi-zone configurations allow mixing compatible one-way cassettes with other indoor styles. Confirm compatibility for your condenser model before ordering.
DIY Quick Connect line sets
The “pre-charged” component is the DIY Quick Connect line set (when included/selected). Follow the install manual for required accessories, connections, and any long-line rules.
Electrical & breaker sizing
Use MCA (23) and Max Fuse/Breaker (25) as starting points, then size per the installation manual and local code.
Line sizing
Indoor line sizes: 1/4 / 3/8 | 1/4 / 1/2. Confirm final line sizes and allowable lengths for your exact pairing before selecting a line set.
