SplitAtlas

Cosmo / Cosmo Series

Cosmo 12k R-32 208/230V Mini-Split

Certified capacity
12,000 BTU/h[4]
SEER2
19 SEER2[4]
Heating floor
-13 F[1]
Voltage
230 V[1]
Install path
Professional install / DIY-marketed

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.

1 zoneProfessional install / DIY-marketedCurrent

Refrigerant generation

R-32 - current-generation refrigerant

Paid link

$810 / Fresh price - checked Jul 24, 2026

Check price at TOSOT Direct

Need this installed?

Get installation quotes
Error Codes
Data completeness: 98%
Last sourced
Aug 17, 2026

SplitAtlas score

7.8 / 10

Methodology
Cooling efficiencyBottom quartile

(19.0 SEER2) among 12k systems

Heating efficiencyBottom quartile

(8.5 HSPF2) among 12k systems

Cold-weather performanceAbove average

(75.8% heat retained at 5F; -13 F heating floor) among 12k systems

WarrantyBottom quartile

(5 yr parts / 5 yr compressor) across the catalogue

Feature setTop quartile

(6 verified features) across the catalogue

Price-to-performanceAbove average

($810 median retail) among 12k systems

Documentation & partsTop quartile

(4 manuals; spec sheet; 14 error-code rows) across the catalogue

Key ratings

Rated cooling

12,000BTU/h[4]

Rated heating

12,000BTU/h[4]

Buyer review snapshot

Install difficulty

Professional flared-line install
  • Electrical: 230V; MCA 12 A; breaker/fuse 15 A.
  • Line set: Flared line connections; included 16 ft; max 65 ft.

Alternatives

Availability and price context

  • Verified current price: $809.99 at TOSOT Direct; availability in_stock; checked Jul 24, 2026.

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

Warranty: 5 years parts and compressor as standard.

Review methodology

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]
Rated 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

Show
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
Standard: 5 yr parts / 5 yr compressor (published Cosmo warranty terms). 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

Check price at TOSOT Direct

$810 / Fresh price - checked Jul 24, 2026

Electrical requirements

Show
Voltage
230 V[1]
Voltage range
208/230V[1]
Phase
1[1]
Frequency
60 Hz[1]
MCA
12 A[1]
Breaker needed
not published
Maximum breaker size
15 A[1]
Maximum fuse size
15 A[1]
Maximum cooling current
not published
Maximum heating current
not published
Manufacturer wire notes
3*16AWG; 230V 30-Amp Double Pole[1]

Installation considerations

Show
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

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 manufacturer publishes 9,100 BTU/h of heating output 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, and the included line set comes pre-charged for 16 ft. Longer runs than the included set allows typically mean added refrigerant and a pro visit, 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: Standard: 5 yr parts / 5 yr compressor (published Cosmo warranty terms). Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.

Data sources

Show
  1. 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

  2. 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, Standard compressor warranty and more

  3. TOSOT Direct / Cosmo: Cosmo Single-Zone 9-24K User ManualSourced - secondary source

    Covers Line connection type

  4. 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

  5. ENERGY STAR: ENERGY STAR exact row check for AHRI 216997533Sourced - Energy Star listing

    Covers Energy Star status

Last updated

Jul 24, 2026