OLMO Sierra 42,000 BTU Outdoor Condenser, 230V, R410A - Mini Split Air Conditioner Heat Pump

Name: OLMO Sierra 42,000 BTU Outdoor Condenser, 230V, R410A - Mini Split Air
Brand: OLMO
SKU: OS-MSR42-230VO
Price: 1857.12 USD
Availability: OutOfStock

White OLMO Sierra 42k BTU R410A ductless mini split outdoor condenser with grille

OLMO5-Yr Warranty

OS-MSR42-230VO

Product specifications

Brand	Olmo
Voltage	230V
SEER	23.4
Type	Outdoor Unit
Freon	R410A
Compressor	Inverter

$1,857.12 Sold out

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Product variants

⛔ Wait! This is an Individual Component To build a working system, this unit must match your other equipment in two ways:

Same Brand Only: Only pair with other same Brand and Series.
Same Refrigerant: Both units must use the exact same gas type (R454B, R32, or R410A).

Mixing different brands or refrigerant types will cause the system to fail and void your warranty.

Pickup currently unavailable at 3550 Northwest 113th Court

Questions about this system?

Answers in seconds — tap a question below

Sized for about 1800–2400 sq ft. Rule of thumb: ~20 BTU per sq ft, and 12,000 BTU = 1 ton (this unit is 42,000 BTU (3.5-ton)). Ceiling height, insulation, sun and climate shift that — if you're between sizes, size up for hot/humid rooms. Not sure? We'll confirm the right BTU for your space.
12,000 BTU = 1 ton — "tons" is just the older way of stating capacity. So 24,000 BTU = 2 tons, 36,000 = 3 tons, and so on. This system is 42,000 BTU (3.5-ton). BTU tells you the capacity; SEER2 tells you the efficiency.
It uses R410A — a proven, widely serviced refrigerant. The outdoor unit ships pre-charged for a standard line set, so most installs need no extra refrigerant; your licensed, EPA-608-certified installer verifies the charge and tops it off if your line set is longer.
Rated SEER2 23.4 — a strong efficiency number, and the higher it is the lower your energy bills. Its inverter compressor ramps up and down instead of cycling on/off, so it holds the temperature steadily, runs quietly, and uses less power than a standard AC or window unit.
Needs a dedicated 230V circuit, like a large household appliance, so it can deliver full capacity to larger rooms and multi-zone setups. Your licensed HVAC installer or electrician sets up the correct breaker and disconnect to meet local electrical code.
Yes — a big upgrade. It's far more efficient (inverter, SEER2 23.4) and much quieter, since the compressor sits outside instead of in your window or on the floor. It mounts permanently, doesn't block a window, and heats as well as cools year-round. Higher upfront cost, but lower bills and a longer lifespan.
Yes to all three. It's an inverter heat pump — cools in summer, heats in winter (even in the cold), far more efficiently than electric heaters. A Dry mode also pulls out humidity, so rooms feel cooler and less muggy.
Ships as a complete set: OS-MSR42-230VO. Everything arrives together — check the photos and specs for the full kit.
It should be installed by a licensed, EPA-608-certified HVAC professional — we don't recommend DIY installation. Handling refrigerant requires EPA Section 608 certification under U.S. law, and professional installation keeps the system safe, code-compliant, and your manufacturer warranty valid.
Yes — you get full inverter heat-pump technology and the same core features as premium brands without paying for the name, which is how we keep prices low. Shipping is free on U.S. orders over $300, and our team can help with sizing and support.

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.

Browse: R-410A systems · R-32 · R-454B

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

Sleek Wall-Mount Design

A slim, quiet indoor head mounts high on the wall and delivers 42000 BTU of heating & cooling — modern looks with whisper-quiet operation.

Inverter Efficiency — SEER2 23.4

A variable-speed inverter compressor ramps to match the load instead of cycling on/off, holding SEER2 23.4 on 230V — steady comfort with noticeably lower energy bills.

Right-Sized Coverage

Engineered to heat & cool up to 1800–2400 sq ft — 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.

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.

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

What size mini split do I need for my space?

The Olmo Sierra 42,000 BTU model is designed to cover a substantial area, making it suitable for larger spaces. Depending on your specific layout and insulation, this unit can effectively cool or heat rooms of varying sizes.

Can I install the Olmo mini split myself?

While it is possible to install the Olmo Sierra ductless mini split yourself, professional installation is recommended for optimal performance. If you opt for a DIY approach, ensure you have the necessary tools and skills to handle the refrigerant lines and electrical connections safely.

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

Yes, the Olmo Sierra mini split comes pre-charged with R410A refrigerant for up to 25 ft of line set, simplifying installation. This feature ensures that you have the right amount of refrigerant for efficient operation right out of the box.

What voltage does the Olmo mini split require?

The Olmo Sierra unit operates on a 230V power supply, making it compatible with standard residential electrical systems in many areas. Ensure your electrical setup can accommodate this voltage for optimal performance.

What warranty does the Olmo Sierra mini split offer?

The Olmo Sierra comes with an impressive 5-year parts and compressor warranty, providing peace of mind regarding the unit's durability and reliability. This warranty covers essential components, ensuring that you are protected against manufacturing defects.

What SEER rating does the Olmo Sierra have and is it efficient?

The Olmo Sierra boasts a high SEER rating of 23.4, indicating its excellent energy efficiency. This level of efficiency can lead to lower energy bills and a reduced environmental impact when cooling or heating your space.