OLMO Sierra 18,000 BTU 2-Zone 9k+12k Wall Mount, 230V, R410A - Ductless Mini Split Air Conditioner Heat Pump | No Kit No Kit

OLMO5-Yr Warranty

OS-MSR18-230VO09WM12WM-NO/NO
Product specifications
Brand Olmo
Voltage 230V
SEER 21
WiFi Included
Zone Dual Zone
Type Wall Mount
Freon R410A
Compressor Inverter
$1,000.24 $930.22 Save 7% Sold out
Shipping Policy calculated at checkout.
9,000 Installation Kit: No Installation Kit
12,000 Installation Kit: No Installation Kit

Pickup currently unavailable at 3550 Northwest 113th Court

Hurry to buy! Get your mini-split system with R-410A refrigerant (offer valid until November 27)
Important info
  • R-410A is being phased down in favor of newer refrigerants; inventory is limited.
  • Existing R-410A systems remain serviceable; parts and qualified service are widely available.
  • Check local codes and rebates. Some incentives prioritize high-efficiency heat pumps (R-32/R-454B).
  • We stock both R-410A and next-gen options—choose what fits your timeline and budget.
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Why buy this mini split from MiniSplitsForLess

  • Free Shipping over $300Ships free to the lower 48 states — flat rate, no surprises at checkout.
  • USA-Based Expert SupportReal U.S. HVAC pros help with BTU sizing, refrigerant and install questions.
  • Genuine Units & Full WarrantyBrand-new, authorized-dealer equipment backed by the full manufacturer warranty.
  • Fast Nationwide ShippingIn stock and ready to ship from U.S. warehouses across all 48 states.

What Stands Out

Complete 2-Zone System

Heat or cool 2 rooms independently from one 18000 BTU outdoor unit (9K+12K) — every zone sets its own temperature, delivered by wall mount indoor units.

Inverter Efficiency — SEER2 21

A variable-speed inverter compressor ramps to match the load instead of cycling on/off, holding SEER2 21 on 230V — steady comfort with noticeably lower energy bills.

Right-Sized Coverage

Engineered to heat & cool up to 500–800 sq ft across 2 zones — matched capacity so you never over- or under-size the space.

Sierra Wall Mount

OLMO's Multi-Zone Sierra Series is a versatile HVAC solution designed to provide efficient heating and cooling for multiple rooms, equipped with advanced inverter technology for precise temperature control and significant energy savings. Using eco-friendly R410A refrigerant, the system ensures reliable performance with minimal environmental impact. Perfect for residential or commercial applications, the Sierra Series offers quiet operation, flexible installation, and user-friendly controls, making it an ideal choice for maintaining year-round comfort across multiple zones with one efficient system.

White multi-zone sierra air conditioner with shield logo and checkmark.

Warranty and Tech Support Info

By selecting OLMO products for your home or business, you’ll receive expert technical support from heating and cooling specialist, including access to product manuals, troubleshooting guides and warranty information.

The manufacturer provides a Limited Warranty of 5 years for the compressor and 2 years for parts.

Warranty terms
White wall-mounted air conditioner with sleek design and modern aesthetic.

Main Features

OLMO's Multi-Zone Sierra Series delivers efficient multi-room comfort with advanced inverter technology for precise temperature control. Its eco-friendly R410A refrigerant reduces environmental impact, while quiet operation ensures minimal disruption. With flexible installation options, sleek design, and reliable heating and cooling, it’s the perfect solution for modern multi-zone climate control needs.

All Accessories Included

With your purchase, you receive a comprehensive MiniSplit system. MiniSplits4Less ensures you have everything needed for a seamless installation. Your package includes an Indoor Unit, Outdoor Unit, Remote Control, Manuals, a 16ft Line Set, and a Smartkit (WIFI). We've meticulously thought of every detail to provide you with all the essentials for your installation.

Technical Specifications

Indoor Models OS-M09SRW-230VI OS-M12SRW-230VI OS-M18SRW-230VI OS-M24SRW-230VI
Power Supply V-Ph-Hz 208/230V-1Ph-60 208/230V-1Ph-60 208/230V-1Ph-60 208/230V-1Ph-60
Cooling
Capacity Btu/h 9000 12000 18000 23400
Heating
Rated Capacity Btu/h 9500 13000 19000 26000
Output Power W 25 25 35 35
Rated Current A 0.11 0.11 0.17 0.17
Indoor Air Flow CFM 341 365 647 706
Indoor Noise Level (Hi/Mi/Lo) dB(A) 39/35/30 39/35/30 45/41/37 47/45/42
Net Dimensions (WxHxD) in 32.02x10.75x8.13 37.38x10.75x8.13 48x12.63x9.25 48x12.63x9.25
Packing (WxHxD) in 39.38x13.19x6.38 39.38x13.19x6.38 51.75x15.44x12.50 51.75x15.44x12.50
Net/Gross Weight lbs 19.84 / 24.25 19.84 / 24.25 31.97 / 37.48 31.97 / 37.48
Refrigerant Piping
Liquid Side / Gas Side in 1/4" / 3/8" 1/4" / 3/8" 1/4" / 1/2" 3/8" / 5/8"
Outdoor Models OS-MSR18-230VO OS-MSR24-230VO OS-MSR36-230VO OS-MSR42-230VO
Power Supply V-Ph-Hz 208/230V-1Ph-60 208/230V-1Ph-60 208/230V-1Ph-60 208/230V-1Ph-60
Capacity Btu/h 18000 24000 32000 42000
Cooling
EER2 Btu/h 12.5 12.5 12.5 10.5
SEER2 Btu/h 21.0 22.0 21.0 20.0
Heating
Rated Capacity Btu/h 18000 24000 36000 42000
HSPF2 Btu/h 9.50 9.05 9.00 8.95
COP2 W/W 3.45 3.66 3.37 3.17
Minimum Circuit Ampacity A 23 25 32.2 35
Max Fuse A 30 30 50 50
Outdoor Air Flow (Hi) CFM 1850 2350 3411 3411
Outdoor Side Noise Level dB(A) 55 55 59 63
Dimensions (WxHxD) in 33.88×26.38×12.25 37.38×33×13.38 37.38×41.38×13.38 37.38×41.38×13.38
Outdoor Unit Packing (WxHxD) in 39×17.75×28.75 43.75×18.13×36.25 43.75×18.13×47.25 43.75×18.13×47.25
Net/Gross Weight lbs 116.8/125.6 158.7/169.5 188.5/220.5 198.4/224.5
Refrigerant
Refrigerant Type/Quantity oz R410A/63.49 R410A/81.13 R410A/105.82 R410A/120
Refrigerant Precharge ft 50 75 98 98
Refrigerant Piping
Liquid Side / Gas Side in 1/4" / 3/8" 1/4" / 3/8" 1/4" / 3/8" 1/4" / 3/8"
Max Refrigerant Pipe Length Each/Total ft 82/164 66/197 66/246 66/262
Ambient Temperature
Outdoor (Cooling) °F 14~114.8 14~114.8 14~114.8 14~114.8
Outdoor (Heating) °F -13~75.2 -13~75.2 -13~75.2 -4~75.2

Multiple Control Methods

Olmo’s can be managed with a user-friendly remote control. This options offer precise temperature adjustments and optimal climate control for ultimate convenience.

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Frequently Asked Questions

How many rooms can the Olmo 2 Zone 18,000 BTU mini split cool?

The Olmo 2 Zone 18,000 BTU mini split is designed to efficiently cool up to 850 sq ft, making it suitable for two medium-sized rooms. With a 9k+12k configuration, you can effectively manage the climate in different spaces simultaneously.

Can I mix BTU sizes with the Olmo mini split system?

Yes, the Olmo 2 Zone mini split allows you to mix BTU sizes across zones, like the 9,000 BTU and 12,000 BTU units. This flexibility can help tailor the system to your specific cooling needs based on room size and usage.

Do all zones in the Olmo 2 Zone mini split run simultaneously?

In the Olmo 2 Zone mini split system, each zone can operate independently, allowing you to cool or heat one zone without affecting the other. This feature is beneficial for energy efficiency and comfort.

What is the efficiency of the Olmo mini split compared to multiple single-zone units?

With a SEER rating of 21.0, the Olmo 2 Zone mini split is highly efficient and can outperform multiple single-zone units combined. This efficiency can lead to lower energy costs and improved overall comfort throughout your home.

What warranty does the Olmo mini split offer?

The Olmo 2 Zone mini split comes with a 5-year parts and compressor warranty, ensuring you have reliable support for your investment. This warranty provides peace of mind for any potential repairs or replacements.

Does the Olmo mini split come pre-charged with refrigerant?

Yes, the Olmo 2 Zone mini split is pre-charged with R410A refrigerant for up to 25 ft of line set, simplifying installation. This feature ensures that the system is ready to operate efficiently right out of the box.