MRCOOL Olympus Multi-Zone 4th Gen — Multi-Zone Mini-Split Heat Pump System
MRCOOL Olympus 4th Generation 2-Zone Ducted Mini Split AC & Heat Pump 18000 BTU (12K+12K), Slim Duct Units, 230V
Concealed slim-duct comfort with a discreet, flush installation—premium efficiency and smart control for professionally installed zoning.
Overview
18000 BTU
2 Zones
25.1 SEER2
Operates to -13°F
Concealed Slim Duct
Wired Controller + Remote
R-454B
The Olympus Duct Air Handler features a ceiling-integrated design for a discreet, flush installation that blends into your space—ideal where aesthetics and space efficiency matter.
System Combination
MULTI3-18HP230C-O + 2X DUCT-12HP-230B-O
MULTI3-18HP230C-O + 2X DUCT-12HP-230B-O
Outdoor Model
MULTI3-18HP230C-O
MULTI3-18HP230C-O
Min Circuit Ampacity
16.0
16.0
Max Fuse / Breaker
20
20
Install note: This is not a DIY system—installation must be completed by an authorized dealer/specialist.
Why Homeowners Love It
- Discreet look: Ceiling-integrated, flush installation that blends into modern interiors.
- Convenient controls: Includes both a wall-mounted wired controller and a handheld remote for simple daily use.
- Multi-zone flexibility: Combine ducted handlers with other compatible indoor styles as needed (system runs in heat or cool mode across the system).
- High efficiency: Advanced inverter technology supports excellent SEER2/HSPF2 performance (model dependent).
- Eco-conscious refrigerant: R-454B.
What’s Included
- (1) Outdoor condenser: MULTI3-18HP230C-O
- Indoor units (slim-duct / concealed duct air handlers):
- 12,000 BTU (x2) — Model: DUCT-12HP-230B-O
Refrigerant line sets and install materials may be option-based: if an installation kit is not selected, it will not be included. Select the appropriate line length for each indoor unit based on your layout.
Mrcool Olympus Multi-Zones
Key Features
- Ceiling-integrated slim duct design for a sleek, space-saving installation.
- Controls included: wired wall controller + handheld remote for easy day-to-day adjustments.
- Smart control options: SmartHVAC app and voice assistants (Alexa/Google) plus included controls (varies by configuration).
- Reliability features: sleep mode, auto restart, and refrigerant leak detection designed to keep the system running smoothly.
- Eco-conscious refrigerant: R-454B.
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
Common coverage includes a 7-year compressor warranty and a 5-year parts warranty (when professionally installed; registration/terms apply).
Extended limited lifetime replacement coverage may be available when enrolled in the MRCOOL® Care Kit Program (fees/conditions apply).
Indoor Specs
Indoor Unit Specifications — DUCT-12HP-230B-O
| brand name | MRCOOL |
|---|---|
| series | Olympus Duct |
| model | DUCT-12HP-230B-O |
| unit type | Mini-Split |
| short description | Olympus 12,000 BTU 1 Ton Ducted Mini-Split Air Handler - 230V/60Hz |
| long description | The MRCOOL® OLYMPUS 12K DUCT Air Handler delivers efficient and reliable heating and cooling for spaces up to 550 square feet, making it a great choice for bedrooms, home offices, and similarly sized areas. Designed for a discreet ceiling installation, the unit offers a flush-mount finish that seamlessly integrates with your space, enhancing the room’s aesthetic with a clean, modern look. Its compact and versatile design suits both residential and commercial applications, providing an ideal climate solution without sacrificing valuable square footage. For added convenience, the system includes both a wired wall-mounted controller and a handheld remote. Whether you prefer adjusting settings from the wall or without leaving the comfort of your couch, climate control is always within easy reach. This model features R-454B refrigerant, a high-efficiency, environmentally friendly option that delivers outstanding performance while minimizing environmental impact. With a low global warming potential, R-454B supports sustainability and helps reduce your household’s carbon footprint, all without compromising system effectiveness or energy efficiency. The MRCOOL® OLYMPUS 12K DUCT Air Handler is backed by a limited lifetime warranty, along with 7-year compressor protection and a 5-year parts warranty—ensuring long-lasting performance and peace of mind. For those seeking energy-conscious comfort, modern design, and reliable climate control, this unit offers a high-performance solution tailored to today’s demands. |
| works with | O-ES-12-HP-C-230C-O1 MULTI3-18HP230C-O MULTI4-27HP230C-O MULTI5-36HP230C-O MULTI6-48HP230C-O |
| tonnage | 1.0 |
| voltage (v) | 208/230 |
| phase | 1 |
| cycle (hz) | 60 |
| max fuse breaker (a) | 15 |
| min circuit ampacity (a) | 3.0 |
| mount type | Ducted |
| color | Metal |
| max coverage area | Up to 550 |
| refrigerant type | R-454B |
| decibel rating (dba) | 36/36/34.5/32.5/25.5 |
| decibel rating low (dba) | 25.5 |
| decibel rating high (dba) | 36.0 |
| air flow direction | Ducted |
| number of speeds | 5 (Variable) |
| oscillation | No |
| lineset fitting type | Flare |
| liquid line size | 1/4 |
| suction line size | 3/8 |
| blower motor speeds | 400.2/323.7/264.9/176.6/117.7 |
| blower motor rpm | 780/680/580 |
| auxiliary heater included | No |
| auxiliary heater available | No |
| fan only option | Yes |
| sleep mode | Yes |
| auto cool | Yes |
| wifi compatibility | No |
| app compatibility | No |
| works with ios | No |
| works with android | No |
| remote control included | Yes |
| ul listed | Yes |
| csa listed | Yes |
| etl listed | Yes |
| base warranty | 5-Year Parts |
| base parts warranty | 5-Year |
| base remote warranty | 5 Year |
| registered labor warranty | None |
| base labor warranty | None |
| has batteries | Yes |
| contains electronics | Yes |
| contains chemicals | Yes |
| contains compressed gas | Yes |
| proposition 65 warning | Yes |
| restricted states | GU, PR, VI |
| net depth (in) | 19.92 |
| net height (in) | 7.87 |
| net width (in) | 27.56 |
| net weight | 39.46 |
| gross weight (lbs) | 46.74 |
Manuals
- https://doxrepo.mrcool.com/mc-oly-mz-4g-duct-im-en-01.pdf
- https://doxrepo.mrcool.com/mc-oly-mz-4g-duct-wt-im-en.pdf
- https://doxrepo.mrcool.com/mc-oly-mz-4g-duct-9-18-sm-en-01.pdf
Documents
Warranty
Outdoor Specs
Outdoor Unit Specifications — MULTI3-18HP230C-O
| brand name | MRCOOL |
|---|---|
| series | Olympus 4th Gen Multi-Zone Condensers |
| model | MULTI3-18HP230C-O |
| unit type | Mini-Split |
| short description | Olympus 18,000 BTU Mini-Split Condenser - 230V/60Hz |
| long description | The MRCOOL® Olympus MULTI3-18HP230C-O is a high-performance 18,000 BTU multi-zone heat pump condenser designed to power up to three indoor units simultaneously. Perfect for homeowners looking to efficiently manage temperatures in multiple spaces, this ductless system offers individualized climate control for each connected zone, making it a flexible solution for modern living environments. Built with advanced inverter technology, the unit delivers impressive efficiency, with SEER2 ratings up to 25.1 and HSPF2-4 up to 10. It performs reliably in diverse conditions, operating in outdoor temperatures as low as 5°F, ensuring comfort in both summer and winter months. This model is compatible with various MRCOOL indoor units, including wall-mounted, ceiling cassette, and concealed duct options, giving users the freedom to tailor the system to their home’s layout and aesthetics. Smart features elevate user convenience, with control options that include the MRCOOL SmartHVAC app, traditional remotes, or even voice commands via Amazon Alexa and Google Assistant. Additional functions such as sleep mode, auto restart, and refrigerant leak detection contribute to enhanced safety and comfort. Backed by a 7-year warranty on the compressor and 5 years on parts (with professional installation), the MRCOOL®Olympus MULTI3-18HP230C-O is a reliable and energy-efficient choice for those seeking customized, zone-specific heating and cooling. |
| works with | O-09-HP-WMAH-230C-O DUCT-09HP-230B-O CASSETTE09HP-230C-O O-12-HP-WMAH-230C-O DUCT-09HP-230B-O CASSETTE12HP-230C-O |
| feature list | Installation by a licensed professional required where applicable 7-Year Compresser, 5-Year Parts warranty when registered and installed by a licensed professional R-454B environmentally friendly refrigerant Energy Star Certified |
| seer2 | Up to 25.1 |
| eer2 | Up to 14 |
| hspf2-4 | 9.8 |
| hspf2-5 | 7.8 |
| tonnage | 1.5 |
| cooling capacity (btu) | 18000.0 |
| heating capacity (btu) | 19000.0 |
| voltage (v) | 208/230 |
| phase | 1 |
| cycle (hz) | 60 |
| max fuse breaker (a) | 20 |
| min circuit ampacity (a) | 16.0 |
| color | White |
| max coverage area | Up to 750 |
| zone capacity | 3.0 |
| refrigerant type | R-454B |
| refrigerant volume (oz) | 61.73 |
| decibel rating (dba) | 59.5 |
| inverter | DC |
| max lineset length (ft) | 196.8 total |
| lineset fitting type | Flare |
| compressor motor type | Twin-Rotary |
| condenser fan motor rpm | 750/600/500 |
| metering device | EXV + Capillary |
| ul listed | Yes |
| csa listed | Yes |
| etl listed | Yes |
| energy star certified | Yes |
| ahri certified | Yes |
| base warranty | 5-Year Parts/7-Year Compressor |
| base parts warranty | 5-Year |
| base compressor warranty | 7-Year |
| base remote warranty | 5 Year |
| registered labor warranty | None |
| base labor warranty | None |
| has batteries | Yes |
| contains electronics | Yes |
| contains chemicals | Yes |
| contains compressed gas | Yes |
| proposition 65 warning | Yes |
| restricted states | GU, PR, VI |
| net depth (in) | 13.46 |
| net height (in) | 26.5 |
| net width (in) | 35.04 |
| net weight | 100.53 |
| gross depth (in) | 17.24 |
| gross height (in) | 29.53 |
| gross width (in) | 40.55 |
| gross weight (lbs) | 109.35 |
Manuals
- https://doxrepo.mrcool.com/mc-oly-mz-4g-im-um-en-01.pdf
- https://doxrepo.mrcool.com/mc-oly-mz-4g-sm-en-01.pdf
Documents
Warranty
Helpful Notes
Professional installation required
Installation must be performed by an authorized dealer/specialist. Improper installation can cause water leakage, electrical shock, or fire.
System operation (heat vs cool)
Multi-zone condensers can heat or cool multiple rooms, but they cannot do both at the same time. The system runs entirely in heating or cooling mode.
Refrigerant piping, evacuation, and line set selection
This system requires standard professional refrigerant piping practices, including evacuation with a vacuum pump/manifold gauge per the installation manual. Select the correct line length for each head; if an installation kit is not selected, it will not be included.
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.
