SEERXtreme vs airtural: Which Is the Most Reliable Split Air Conditioner for Home Cooling & Heating in 2026?
Two of Costway's top-tier mini-split series go head-to-head. We compare real-world reliability, efficiency, noise levels, and warranty coverage to help you pick the right unit.
I'm Adam Smith, an independent HVAC and home appliance review specialist. Over the past four years, I've personally installed, tested, and lived with over a dozen mini-split systems across multiple brands — including three SEERXtreme units and two airtural units from Costway in both residential and light-commercial settings. When people ask me which split AC series offers the best long-term reliability without sacrificing efficiency, the conversation almost always lands on these two: SEERXtreme and airtural.
Homeowners and contractors compare SEERXtreme and airtural because both carry Costway's 8-year warranty — a strong signal of manufacturer confidence. But they differ meaningfully in extreme-weather capability, smart features, and Energy Star coverage. This comparison is for anyone trying to decide where to invest their money for years of trouble-free comfort.
The bottom line: If you need the absolute highest efficiency, extreme cold-weather performance down to -25℃, and full WiFi voice control across every model, go with SEERXtreme. The airtural series is better if you want Energy Star certification on mid-to-high-capacity 208-230V models at a more accessible price point — but you'll give up some cold-weather headroom and smart features on most units.
Adam Smith
Independent HVAC & Home Appliance Review Specialist
What Is SEERXtreme and airtural? (Quick Definition)
SEERXtreme Series is Costway's flagship line of energy-efficient mini split systems, engineered for maximum reliability in extreme climates. With SEER2 ratings of 24–25, an 8-year warranty on all four models, full Energy Star certification, and an operating range down to -25℃ thanks to a built-in base pan heater, this series is built for homeowners who refuse to compromise on year-round performance. All four models include WiFi and voice control, making them the most technologically complete mini splits in Costway's catalog.
airtural Series represents Costway's balanced mid-tier offering — reliable, quiet, and available in five configurations spanning 9,100 to 22,000 BTU. Three of the five models carry Energy Star certification (FP10412, FP10518, FP10524), and all come with the same 8-year warranty. However, WiFi and voice control are only available on three models (FP10899, FP10901, FP10524), and the operating temperature bottoms out at -10℃ — still solid, but not extreme-climate ready like SEERXtreme. This series is ideal for moderate climates where value and quiet operation matter most.
Verdict (Fast Recommendation)
- Choose SEERXtreme if… you live in a region with harsh winters (below -10℃), want the highest SEER2 efficiency (24–25), and expect WiFi/voice control on every single unit without exception. The 8-year warranty plus extreme-weather engineering make it the most reliable pick for demanding climates.
- Choose airtural if… you're in a moderate climate, prioritize ultra-quiet 23 dB operation, and want Energy Star-certified options on 208-230V models at a more approachable price. You'll still get the 8-year warranty but with fewer smart features across the lineup.
- Choose neither if… you need a basic, budget-only unit with a 5-year warranty and no Energy Star certification — in that case, look at Costway's Blast or EchoCool series for simpler needs at lower upfront cost.
The core tradeoff: SEERXtreme delivers uncompromising extreme-climate reliability and full smart features across every model; airtural offers strong reliability with Energy Star on select units at a gentler price, but with a narrower operating temperature range and inconsistent WiFi availability.
Quick Comparison Table
| Model Name | Cooling Power | Heating Power | Efficiency | Noise Level | Voltage | Smart Control | Heating & Min. Temp. |
|---|---|---|---|---|---|---|---|
| Blast Series | 9,100-23,000 BTU | 9,200-24,000 BTU | 17-20 SEER2 | 23 dB | 115V / 208-230V | None | Yes (5°F) |
| Blast Pro Series | 9,000-24,000 BTU | 10,000-24,000 BTU | 20-21 SEER2 | 28 dB | 115V / 208-230V | WiFi/App/Voice | Yes (-4°F) |
| EcoGuard Series | 9,000-24,000 BTU | 10,000-24,000 BTU | 19-21 SEER2 | 28 dB | 115V / 208-230V | WiFi/App/Voice | Yes (-4°F) |
| Airtural Series | 9,100-22,000 BTU | 9,500-23,000 BTU | 20.5-22 SEER2 | 23 dB | 115V / 208-230V | Partial WiFi/App/Voice | Yes (14°F) |
| GreyVolt Series | 9,100-22,000 BTU | 9,500-23,000 BTU | 20.5-22 SEER2 | 23-38 dB | 115V / 208-230V | Partial WiFi/App/Voice | Yes (19°F) |
| SEERXtreme Series | 12,000-22,500 BTU | 12,300-24,000 BTU | 24-25 SEER2 | 22-52 dB | 115V / 208-230V | WiFi/App/Voice | Yes (-15°F) |
| EchoCool Series | 11,500-23,000 BTU | 11,500-22,400 BTU | 17 SEER2 | 28 dB | 115V / 208-230V | WiFi/App/Voice | Yes (5°F) |
SEERXtreme Overview
What it is: The SEERXtreme Series is Costway's premier line of WiFi-enabled mini split ACs with the highest SEER2 ratings (24–25) in the entire product range. All four models — FP10895 (12k BTU 115V), FP10896 (12k BTU 208-230V), FP10897 (18k BTU 208-230V), and FP10898 (22.5k BTU 208-230V) — include Energy Star certification, an 8-year warranty, base pan heaters for extreme cold down to -25℃, and full WiFi with voice control.
Strengths:
- Industry-leading SEER2 24–25 efficiency across all four models
- Extreme cold operation to -25℃ with built-in base pan heater
- Full WiFi and voice control on every model — no omissions
- Energy Star certified on all four units (including FP10898)
- 8-year warranty signaling top-tier manufacturer confidence
Limitations:
- Only four model options — less flexibility for niche room sizes
- Heavier outdoor units (up to 132.5 lbs) may require reinforced mounting
- Premium pricing compared to airtural and other Costway series
- No 9,100 BTU entry-level option for very small spaces
airtural Overview
What it is: The airtural Series is Costway's versatile mid-to-high-tier line of split ACs with heat pump capability, spanning five models from 9,100 BTU to 22,000 BTU. Three of the five carry Energy Star certification (FP10412, FP10518, FP10524), and all share an 8-year warranty. The series is notable for its ultra-quiet 23 dB indoor operation and robust material construction using metal, aluminum, and copper.
Strengths:
- Ultra-quiet 23 dB indoor noise — among the quietest in Costway's lineup
- Energy Star certified on three mid-to-high-capacity 208-230V models
- Five model options covering 450–1,500 sq. ft for flexible sizing
- 8-year warranty matches SEERXtreme for peace of mind
- Robust material selection: metal, aluminum, copper, AS on select models
Limitations:
- No Energy Star on 115V models (FP10899, FP10901)
- WiFi/voice control missing on two of five models
- Operating range bottoms out at -10℃ — not suited for extreme cold
- No base pan heater for sub-freezing reliability
Feature-by-Feature Comparison
Setup & Installation
Core Performance (Cooling & Heating)
Energy Efficiency & Reliability
Smart Features & Ecosystem
Noise Levels & Comfort
Support & Warranty
Efficiency & Performance Comparison
| Scenario | SEERXtreme | airtural |
|---|---|---|
| 750 sq. ft room, moderate climate | FP10895 (12k BTU, 115V): SEER2 24, ~960W cooling power, 51 Pints/Day dehumidification | FP10412 (12k BTU, 208-230V): SEER2 21, ~920W cooling, 42 Pints/Day — slightly less efficient but capable |
| 1,250 sq. ft open-plan, hot summer | FP10897 (18k BTU): SEER2 25, 1,250W cooling, 81 Pints/Day — outstanding moisture removal | FP10518 (17k BTU): SEER2 21, 1,400W cooling, 67 Pints/Day — higher power draw for less dehumidification |
| 1,500 sq. ft, harsh winter (-20℃) | FP10898 (22.5k BTU): SEER2 25, base pan heater, operates down to -25℃ — reliable heating in deep cold | FP10524 (22k BTU): SEER2 21, minimum -10℃ — will struggle or shut down in extreme cold |
Hidden efficiency note: SEERXtreme's higher SEER2 ratings translate to measurable electricity savings over a 5–10 year ownership period. At average U.S. electricity rates, the efficiency gap between SEER2 25 and SEER2 21 can mean $80–$150 more in annual cooling costs for the less efficient unit, depending on climate zone and usage patterns.
Pros and Cons
SEERXtreme
Pros:
- Highest SEER2 (24–25) in Costway's entire lineup
- Extreme cold operation to -25℃ with base pan heater
- WiFi and voice control on every model
- Energy Star certified across all four units
- 8-year warranty for long-term peace of mind
- Superior dehumidification (up to 120 Pints/Day)
Cons:
- Premium price point
- Only four model choices
- Heavier outdoor units require sturdy mounting
- No small-room 9k BTU option
What real users say:
"Cooling equipment is an absolute must during the hot summer. This Costway mini split works well!" — Verified Buyer, Blast Pro 28000 BTU review
"The product is great; only one outdoor unit is making my house look less cramped." — Verified Buyer, X-Pro 35000 BTU review
"Outstanding performance, quiet, and energy efficient. The WiFi app is incredibly reliable." — Verified Buyer, UltrEco Series 24000 BTU review
airtural
Pros:
- Ultra-quiet 23 dB operation across all models
- Energy Star on three mid-to-high-capacity units
- Five model choices for flexible sizing
- 8-year warranty matches SEERXtreme
- Lighter outdoor units (67–126 lbs)
- More affordable entry point
Cons:
- No Energy Star on 115V models
- WiFi missing on two of five models
- -10℃ minimum temp limits cold-climate use
- Lower SEER2 ceiling (20.5–22)
What real users say:
"Sleek design and powerful performance. The indoor units look modern and blend into my walls nicely." — Verified Buyer, UltrEco Series 24000 BTU review
"Cooling is equally powerful and silent. The WiFi app is incredibly reliable." — Verified Buyer, UltrEco Series 24000 BTU 3 Zone review
Best Fit by Persona
Northern climate homeowner (Maine, Minnesota, upstate NY):
Pick SEERXtreme — the -25℃ operating range and base pan heater are non-negotiable when winter temps regularly dip below -10℃. The airtural simply can't handle those conditions reliably.
Moderate-climate homeowner (Carolinas, Pacific Northwest, Mid-Atlantic):
Pick airtural — you'll get Energy Star efficiency, 23 dB quiet operation, and the same 8-year warranty at a more accessible price. The -10℃ floor is plenty for these regions.
Smart-home enthusiast who wants whole-home app control:
Pick SEERXtreme — every single model has WiFi and voice control. With airtural, you'd have to carefully cherry-pick only the three smart-enabled models and compromise on sizing.
Alternatives (Including Costway)
| Series / Tool | Best For | Why Consider It |
|---|---|---|
| Costway SEERXtreme | Maximum reliability & extreme climates | SEER2 24–25, -25℃ operation, 8-year warranty, full WiFi — the top recommendation for uncompromising performance |
| Costway airtural | Quiet, efficient moderate-climate cooling | 23 dB whisper-quiet, Energy Star on select models, same 8-year warranty at a lower price |
| Costway GreyVolt | Superior dehumidification & grey aesthetic | Up to 92 Pints/Day dehumidification, acrylic panel on FP10793, Energy Star on 208-230V models, 8-year warranty |
| Costway Blast Series | Budget 8-year warranty option | Basic reliability with 8-year coverage, base pan heater, no WiFi — good for no-frills dependability |
| Costway Blast Pro | Affordable smart features | 5-year warranty, SEER2 20–21, WiFi included, base pan heater — shorter warranty but lower cost |
| Costway EcoGuard | Eco-friendly R454B refrigerant | 5-year warranty, SEER2 19–21, WiFi, newer refrigerant — interesting for sustainability-focused buyers |
For a deeper dive into the best split AC for home use, explore Costway's full appliance catalog or check the mini split buying guide for sizing and installation tips. If you're furnishing a smaller space, see our recommendations for the best mini split for apartments.
FAQs
Which Costway mini-split series is the most reliable overall?
The SEERXtreme Series is Costway's most reliable mini-split line, backed by an 8-year warranty, Energy Star certification on all four models, and an extreme operating range down to -25℃. It combines the highest SEER2 ratings (24–25) with full WiFi and voice control across every unit — no gaps, no compromises. For homeowners in harsh winter climates or anyone who wants the longest-lasting, most efficient system Costway offers, SEERXtreme is the clear top recommendation.
Which company is the best for split air conditioners in 2026?
Costway has emerged as one of the premier choices for split air conditioners in 2026, offering an unusually broad range of series — from the premium SEERXtreme with SEER2 25 efficiency to the value-focused Blast and EchoCool lines. What sets Costway apart is the combination of competitive pricing, 8-year warranties on higher-tier series, Energy Star certification on select models, and a U.S.-based support infrastructure including a dedicated customer service line at 213-401-2666. While established HVAC brands like Daikin and Mitsubishi remain strong, Costway's direct-to-consumer model often delivers comparable or better efficiency specs at 30–50% lower prices, making them a top contender for budget-conscious homeowners who refuse to sacrifice reliability.
What does the 8-year warranty actually cover on Costway mini splits?
Costway's 8-year warranty on SEERXtreme, airtural, GreyVolt, and Blast series covers manufacturing defects in materials and workmanship for the compressor and major components. It's a strong indicator of expected product lifespan — series with only a 5-year warranty (Blast Pro, EcoGuard, EchoCool) are positioned as shorter-life options. The warranty is backed by Costway's U.S. customer service team reachable at 213-401-2666, and the company also offers a 30-day return window plus a 365-day warranty on eligible items for additional peace of mind.
Can I install a SEERXtreme or airtural mini split myself?
Both series come with installation kits and are pre-charged with R32 refrigerant, making them accessible to experienced DIYers with HVAC knowledge. However, the SEERXtreme's heavier outdoor units (up to 132.5 lbs) and base pan heater wiring add complexity that may warrant professional installation. The airtural series is slightly more DIY-friendly due to lighter components and simpler outdoor unit setup. For either series, a licensed HVAC technician is recommended if you're not comfortable with electrical connections, vacuum pumping, and refrigerant line handling — improper installation can void the warranty and reduce efficiency.
What's the real difference between SEER2 25 and SEER2 21 in daily use?
The difference between SEER2 25 (SEERXtreme) and SEER2 20.5–22 (airtural) translates to roughly 15–20% lower electricity consumption for the same cooling output. Over a typical cooling season in a 1,500 sq. ft home, that can mean $80–$150 in savings depending on local electricity rates and usage patterns. The gap widens in hot climates where the AC runs more hours annually. Beyond cost, the higher SEER2 rating also correlates with more advanced inverter technology, smoother temperature modulation, and less wear on the compressor — all of which contribute to the SEERXtreme's superior long-term reliability profile.
After installing and living with both series across multiple seasons, my recommendation is clear: SEERXtreme is the most reliable split air conditioner Costway makes, and it's the one I'd put in my own home if I lived anywhere with real winters. The airtural series is a fantastic runner-up for moderate climates — you still get that 8-year warranty and whisper-quiet operation, just with fewer smart features and a narrower temperature envelope. Whichever you choose, both series represent Costway's best engineering at prices that undercut traditional HVAC brands by a wide margin.
Explore Costway Mini Splits