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What Stands Out
Complete 2-Zone System
Heat or cool 2 rooms independently from one 18000 BTU outdoor unit (9K+9K) — 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.
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.
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.
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 can effectively cool up to two rooms, typically covering a total area of up to 850 sq ft. This dual-zone system allows for individual temperature control in each space.
Can I mix BTU sizes in the Olmo mini split system?
Yes, you can mix BTU sizes in your Olmo mini split system as long as the total BTU does not exceed the system's capacity. For example, the Olmo 18,000 BTU unit can be paired with smaller units like 9,000 BTU for each zone, optimizing efficiency.
Do all zones run simultaneously in the Olmo multi-zone mini split system?
Yes, all zones in the Olmo multi-zone 18,000 BTU mini split system can run simultaneously. This allows for customized comfort in each room while maintaining an energy-efficient operation with a SEER rating of 21.0.
What is the warranty for the Olmo mini split system?
The Olmo mini split system comes with a comprehensive 5-year parts and compressor warranty, ensuring reliable performance and peace of mind for your investment in comfort.
Does the Olmo mini split come pre-charged with refrigerant?
Yes, the Olmo mini split system is pre-charged with R410A refrigerant for up to 25 ft of line set, making installation easier and more efficient for homeowners. This ensures optimal cooling performance right from the start.
Is the Olmo mini split good for heating in cold weather?
The Olmo 2 Zone 18,000 BTU mini split is designed to provide effective heating in cold weather, making it a versatile choice for year-round comfort. With a SEER rating of 21.0, it efficiently maintains comfortable temperatures even in lower outdoor conditions.
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