Cosmo / Cosmo Series
Cosmo 12k R-32 208/230V Mini-Split
The Cosmo 12k (230V) is the dedicated-circuit 1-ton: SEER2 19, EER2 9.75, HSPF2 8.5 on R-32, with 12,000 BTU at 47F, 9,700 BTU at 17F and 9,100 BTU at 5F. The 230V version holds noticeably more heat at 5F than its 115V sibling (9,100 vs 8,500 BTU) and is ENERGY STAR certified.
Refrigerant generation
R-32 - current-generation refrigerant
Paid link
$810 / Checked Jul 24, 2026
Need this installed?
Get installation quotes- Last sourced
- Aug 17, 2026
SplitAtlas score
7.8 / 10
(19.0 SEER2) among 12k systems
(8.5 HSPF2) among 12k systems
(5F certified capacity: 75.8% of the 47F rating; -13 F heating floor) among 12k systems
(5 yr parts / 5 yr compressor) across the catalogue
(6 verified features) across the catalogue
($810 median retail) among 12k systems
(4 manuals; spec sheet; 14 error-code rows) across the catalogue
Key ratings
Buyer review snapshot
Install difficulty
- Electrical: 230V; MCA 12 A; breaker/fuse 15 A.
- Line set: Flared line connections; included 16 ft; max 65 ft.
Alternatives
- Blueridge XS6 Max Efficiency 12,000 BTU R-454B 208/230V (BXS6A12WM0 / BXS6A12UC0)
9.0 score / 12k / SEER2 29.4 / -22 F heating floor / 230V
Exact destination at Alpine Home Air: $1,979.00, checked Jul 24, 2026
- Senville ELITE 12,000 BTU R-454B 208/230V (SENE-12EL-IHH / SENE-12EL-OH)
8.9 score / 12k / SEER2 29.4 / -22 F heating floor / 187-253V
Exact destination at Senville: $1,699.99, checked Jul 24, 2026
- ACiQ Extreme 12,000 BTU R-454B 208/230V (ACIQ-12W-HH-MD / ACIQ-12ZPL-HP230C)
8.9 score / 12k / SEER2 25.4 / -22 F heating floor / 230V
Exact destination at HVACDirect: $1,649.99, checked Jul 26, 2026
Availability and price context
- Last seen at TOSOT Direct on Jul 24, 2026: $809.99. Open the listing for today's price.
Source date
- Model data sourced
- Aug 17, 2026
- Page reviewed
- Jul 24, 2026
- Source-backed records
- 5
- Newest source retrieved
- Aug 17, 2026
Warranty tiers
- Base
- 5 yr parts / 5 yr compressor - published Cosmo warranty terms
The score uses Base. Additional published terms are shown for reference and not counted in the score.
Strengths
- Holds 9,100 BTU of heat at 5F - strong retention for a value 1-ton unit.
- ENERGY STAR certified with current R-32 refrigerant; Gree-built.
Weaknesses
- EER2 9.75 / SEER2 19 - modest efficiency for the tier.
- Value-brand support network; professional install recommended.
Climate suitability
- Minimum heating ambient
- -13 F[1]
- Certified heating at 5F
- 9,100 BTU/h[4]
- Rated heating at 17F
- 9,700 BTU/h[4]
- Rated heating at 47F
- 12,000 BTU/h[4]
Specifications
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- Manufacturer
- Cosmo
- Brand
- Cosmo
- Product line
- Cosmo Series
- Model number
- GWH12AWCXB-D6DN*/I indoor / GWH12ATCXB-D6DNA1A/O outdoor
- Indoor unit model
- GWH12AWCXB-D6DN*/I
- Outdoor unit model
- GWH12ATCXB-D6DNA1A/O
- Number of zones
- 1
- Max indoor units
- not published
- Rated cooling capacity
- 12,000 BTU/h[4]
- Rated heating capacity
- 12,000 BTU/h[4]
- Voltage
- 230 V[1]
- MCA
- 12 A[1]
- Maximum fuse or breaker size
- 15 A[1]
- Breaker needed
- not published
- SEER2
- 19 SEER2[4]
- EER2
- 9.75 EER2[4]
- HSPF2 (Region 4)
- 8.5 HSPF2[4]
- HSPF2 (Region 5)
- not published
- COP
- not published
- COP at 47F
- not published
- COP at 5F
- 1.8 COP[4]
- Minimum outdoor heating temperature
- -13 F[1]
- Minimum outdoor cooling temperature
- -13 F[1]
- Maximum outdoor temperature
- 118 F[1]
- Indoor noise range
- 47/22 dB(A)[1]
- Outdoor noise rating
- not published
- Indoor weight
- 19.8 lb[1]
- Outdoor weight
- 56.2 lb[1]
- Refrigerant
- R-32[4]
- Refrigerant charge
- not published
- Manufacturer coverage
- not published
- Line-set size
- 1/4 in liquid / 3/8 in suction
- Included line-set length
- 16 ft[2]
- Maximum line-set length
- 65 ft[1]
- Max line set per indoor
- not published
- Maximum elevation difference
- 40 ft[1]
- Max height between indoor units
- not published
- Wi-Fi support
- supported[2]
- Energy Star status
- ENERGY STAR certified[5]
- AHRI certification number
- 215684457[4]
- Warranty
- Base: 5 yr parts / 5 yr compressor (published Cosmo warranty terms). Score uses Base.. 5-year TOSOT Direct Cosmo product-page warranty
- Install path
- Professional install / DIY-marketed
- Marketing install label
- DIY-marketed
- Retail price
- $809.99
- Available retailers
- TOSOT Direct
- Manual links
- Cosmo Single-Zone 9-24K User Manual, TOSOT Direct product documents page for Cosmo Series manuals, 12,000 BTU Mini-Split Heat Pump Air Conditioner-230V product-page specifications, TOSOT Cosmo Series brochure specifications for GWH12ATCXB-D6DNA1A
- Specification sheet
- 12,000 BTU Mini-Split Heat Pump Air Conditioner-230V product-page specifications
- Last sourced date
- Aug 17, 2026
Retail purchase context
Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure
Paid link
$810 / Checked Jul 24, 2026
Electrical requirements
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Installation considerations
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- Liquid line
- 1/4 in[1]
- Suction line
- 3/8 in[1]
- Line connection type
- Flared line connections[3]
- Precharged length
- not published
- Included line-set length
- 16 ft[2]
- Maximum line-set length
- 65 ft[1]
- Max line set per indoor
- not published
- Max height between indoor units
- not published
- Indoor dimensions
- 32.9 in W x 10.8 in H x 7.9 in D[1]
- Outdoor dimensions
- 28.8 in W x 21.9 in H x 13 in D[1]
- Indoor weight
- 19.8 lb[1]
- Outdoor weight
- 56.2 lb[1]
- Drain size
- not published
Related systems and guides
- More Cosmo systems
- Cosmo 12k R-32 115V Mini-Split
- Daikin ATMOSPHERA 12k R-32 208/230V Mini-Split
- Cosmo 18k R-32 208/230V 2-Zone Mini-Split
- Cooper Hunter Slim Duct 12k Hyper Concealed Ducted R-454B 208/230V Mini-Split
- Guide library
- Mini split buying guide
- Single-zone vs multi-zone mini splits
- Troubleshooting
- Do mini splits work in cold weather?
- The best 12,000 BTU mini splits of 2026
- The best cold-climate mini splits of 2026
- The best mini splits for heating of 2026
- Mini split heating capacity in the cold: what your unit actually delivers at 5F
- The mini split defrost cycle, explained
- The best DIY mini splits of 2026
- What "DIY mini split" actually means
- How to install a mini split (DIY overview)
- R-32 vs R-454B: the mini split refrigerant change explained
- Mini split not heating
- Mini split indoor unit freezing up
- Mini split remote not working
- Mini split outdoor unit not running
- Mini split Wi-Fi not connecting
- Line sets
- Line-set covers
Frequently asked questions
- Can I install the Cosmo Series 12,000 BTU R-32 208/230V (GWH12AWCXB-D6DN***/I / GWH12ATCXB-D6DNA1A/O) myself, or do I need a pro?
- Cosmo Series 12,000 BTU R-32 208/230V (GWH12AWCXB-D6DN***/I / GWH12ATCXB-D6DNA1A/O) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
- Will the Cosmo Series 12,000 BTU R-32 208/230V (GWH12AWCXB-D6DN***/I / GWH12ATCXB-D6DNA1A/O) keep heating in a cold winter?
- The AHRI/ENERGY STAR certification lists 9,100 BTU/h of heating capacity at 5F. Rated heating operation extends down to -13 F. Certified heating efficiency is 8.5 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
- What electrical circuit does the Cosmo Series 12,000 BTU R-32 208/230V (GWH12AWCXB-D6DN***/I / GWH12ATCXB-D6DNA1A/O) need?
- Published electrical requirements: 230 V voltage, 12 A minimum circuit ampacity, and 15 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
- How far can the outdoor unit be from the indoor head?
- The published maximum line-set length is 65 ft. A 16 ft line set is included. Longer runs than the included set allows require a different line set, so measure the planned routing before ordering.
- What warranty does the Cosmo Series 12,000 BTU R-32 208/230V (GWH12AWCXB-D6DN***/I / GWH12ATCXB-D6DNA1A/O) carry?
- The manufacturer publishes these warranty tiers: Base: 5 yr parts / 5 yr compressor (published Cosmo warranty terms). Score uses Base.. Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.
Data sources
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- TOSOT Direct: TOSOT Residential and Light Commercial Split Systems brochure Cosmo table for GWH09ATCXB-D6DNA1CSourced - manufacturer technical document
Covers Frequency, Maximum breaker size, Maximum fuse size, Minimum circuit ampacity, Phase, Manufacturer wire notes and more
- TOSOT Direct: 12,000 BTU Mini-Split Heat Pump Air Conditioner-230V official product pageSourced - manufacturer product page
Covers Included line-set length, Wi-Fi support, Retail price, Legacy compressor warranty value, Legacy warranty value, Base compressor warranty and more
- TOSOT Direct / Cosmo: Cosmo Single-Zone 9-24K User ManualSourced - secondary source
Covers Line connection type
- AHRI certificate #215684457 - search the AHRI DirectorySourced - AHRI directory
Covers AHRI certification number, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity, HSPF2 (Region 4) and more
- ENERGY STAR: ENERGY STAR exact row check for AHRI 216997533Sourced - Energy Star listing
Covers Energy Star status
Last updated
Jul 24, 2026