MRCOOL DIY 5th Gen — Multi-Zone Mini Split Heat Pump System
MRCOOL DIY 5th Gen 2-Zone Ductless Mini Split AC & Heat Pump 18000 BTU (12K+12K), Wall Mount Units, 230V
A multi-zone heating & cooling system designed for simple setup, smart control, and efficient year-round comfort.
Overview
18000 BTU 2 Zones 23.9 SEER2 Heats to -13°F R-454B Smart App Control Alexa & Google
Take full control of your indoor climate with a DIY-focused multi-zone mini split system that delivers efficient heating, cooling, and dehumidification with independent control in each area.
System Combination
DIY-MULTI3-18HP230D-O + 2X DIY-12-HP-WMAH-230D25-O
DIY-MULTI3-18HP230D-O + 2X DIY-12-HP-WMAH-230D25-O
Outdoor Model
DIY-MULTI3-18HP230D-O
DIY-MULTI3-18HP230D-O
Min Circuit Ampacity
16
16
Max Fuse / Breaker
20
20
Why Homeowners Love It
- 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-MULTI3-18HP230D-O
- Indoor units:
- 12,000 BTU (x2) — Model: DIY-12-HP-WMAH-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)
- Installation accessories & documentation (see Documents & Downloads)
Mrcool DIY Multi-Zones
Key Features
- 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.
- Room-by-room airflow control and washable filters for simple upkeep.
- Display & diagnostics on the indoor unit for quick status checks.
- 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 — DIY-12-HP-WMAH-230D25-O
| brand name | MRCOOL |
|---|---|
| sku | DIY 5th gen Multi-Zone Mini-splits |
| model | DIY-12-HP-WMAH-230D25-O |
| short description | MRCOOL® 12k DIY 5th Generation Mini-Split Air Handler 230v |
| feature list |
|
| voltage (V) | 208/230 |
| phase | 1 |
| cycle (Hz) | 60 |
| mount type | Wall |
| color | White |
| max coverage area | 550 sqft |
| oscillation | Yes |
| liquid line size | 1/4 |
| suction line size | 3/8 |
| filter type | Reusable |
| 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 |
| remote control included | Yes |
| ul listed | Yes |
| etl listed | 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) | 7.44 |
| net height (in) | 11.63 |
| net width (in) | 31.57 |
| net weight | 24.47 |
| gross depth (in) | 16.34 |
| gross height (in) | 14.37 |
| gross width (in) | 36.02 |
| gross weight (lbs) | 35.05 |
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
Outdoor Specs
Outdoor Unit Specifications — DIY-MULTI3-18HP230D-O
| brand name | MRCOOL |
|---|---|
| sku | DIY 5th gen Multi-Zone Mini-splits |
| model | DIY-MULTI3-18HP230D-O |
| short description | MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v |
| feature list |
|
| seer2 | 23.9 |
| eer2 | 13 |
| hspf2-4 | 10 |
| hspf2-5 | 7.8 |
| tonnage | 1.5 |
| cooling capacity (BTU) | 18000 |
| heating capacity (BTU) | 18000 |
| voltage (V) | 208/230 |
| phase | 1 |
| cycle (Hz) | 60 |
| max fuse breaker (a) | 20 |
| min circuit ampacity (a) | 16 |
| color | White |
| zone capacity | 3 |
| refrigerant type | R-454B |
| refrigerant volume (oz) | 61.73 |
| decibel rating (dba) | 60 |
| inverter | DC |
| line set length | 25 |
| max lineset length (ft) | 172.2 |
| 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) | 13.46 |
| net height (in) | 26.5 |
| net width (in) | 35.04 |
| net weight | 101.63 |
| gross depth (in) | 17.24 |
| gross height (in) | 29.53 |
| gross width (in) | 40.55 |
| gross weight (lbs) | 109.57 |
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 wall mounts and 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 (16) and Max Fuse/Breaker (20) as starting points, then size per the installation manual and local code.
Line sizing
Indoor line sizes: 1/4 / 3/8. Confirm final line sizes and allowable lengths for your exact pairing before selecting a line set.
