SplitAtlas

Cosmo / Cosmo Multi-Zone

Cosmo 18k R-32 208/230V 2-Zone Mini-Split

Certified capacity
18,000 BTU/h[2]
SEER2
21 SEER2[2]
Heating floor
-22 F[1]
Voltage
230 V[1]
Install path
Professional install

The Cosmo Multi-Zone 2-zone runs two rooms from one 208/230V outdoor unit on R-32 refrigerant, with a certified nominal SEER2 of 21 (EER2 12, HSPF2 10), ENERGY STAR certified and AHRI cold-climate designated. That certified figure is the all-non-ducted nominal; your real efficiency depends on the heads you attach.

Heating is rated 18000 BTU at 47F, 16000 at 17F, and 13800 at 5F, so output tapers in deep cold - size for your coldest design day. Cosmo is a value brand sold direct through TOSOT Direct (part of the TOSOT/Gree family), professionally installed and priced by quote.

2 zonesProfessional installCurrent

Refrigerant generation

R-32 - current-generation refrigerant

Need this installed?

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Error Codes
Data completeness: 97%
Last sourced
Jul 29, 2026

SplitAtlas score

8.0 / 10

Methodology
Cooling efficiencyBelow average

(21.0 SEER2) among 18k systems

Heating efficiencyAbove average

(10.0 HSPF2) among 18k systems

Cold-weather performanceAbove average

(76.7% heat retained at 5F; -22 F heating floor) among 18k systems

WarrantyBottom quartile

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

Feature setBelow average

(4 verified features) across the catalogue

Documentation & partsBelow average

(6 manuals; spec sheet) across the catalogue

Not evaluated

  • Installation accessibility — not applicable (professional install)N/A

    professional install - DIY-accessibility not applicable

  • Price-to-value — not evaluatedN/A

    This is a professionally installed, quote-only system, so we can't score its price. Get an installed quote to compare real cost.

    Get a quote

Key ratings

Rated cooling

18,000BTU/hNon-Ducted Indoor Units[2]

Rated heating

18,000BTU/hNon-Ducted Indoor Units[2]

Buyer review snapshot

Best for / skip if

Best for

  • 2-zone projects in the 18k outdoor capacity class.

Install difficulty

Complex professional install
  • Electrical: 230V; MCA 14.5 A; breaker/fuse 20 A.
  • Line set: connection type not sourced; max 328 ft.
  • 2-zone condenser; indoor-head matching and branch layout are part of the job.

Alternatives

Availability and price context

We could not verify a current retail price for this model. These TOSOT/Cosmo multi-zone systems are professional-install equipment, so we link to contractor quotes rather than a retail price.

Source date

Model data sourced
Jul 29, 2026
Page reviewed
Jul 29, 2026
Source-backed records
4
Newest source retrieved
Jul 29, 2026

Warranty tiers

Warranty: 5 years parts and compressor as standard.

Review methodology

Model context

Install path
This is professional-install equipment; no verified current retail offer is attached.
Structured ratings
Certification: ENERGY STAR certified, ENERGY STAR cold-climate certified and AHRI cold-climate designated. Refrigerant: current low-GWP R-32. Minimum heating ambient: -22 F.

Strengths

  • Two zones from one outdoor unit and a single 208/230V circuit on current R-32 refrigerant.
  • Certified nominal SEER2 21 / EER2 12 / HSPF2 10, ENERGY STAR certified.
  • AHRI cold-climate designated, with 13800 BTU of heat still rated at 5F.

Weaknesses

  • Heating tapers in deep cold (16000 at 17F, 13800 at 5F versus 18000 at 47F).
  • Two-zone total capacity is shared; size to the condenser, not two full rooms.

Climate suitability

Minimum heating ambient
-22 F[1]
Rated heating at 5F
13,800 BTU/hNon-Ducted Indoor Units[2]
Rated heating at 17F
16,000 BTU/hNon-Ducted Indoor Units[2]
Rated heating at 47F
18,000 BTU/hNon-Ducted Indoor Units[2]

Specifications

Show
Manufacturer
Cosmo
Brand
Cosmo
Product line
Cosmo Multi-Zone
Model number
MZ-COSMO18/O
Indoor unit model
Indoor heads are selected separately on a multi-zone system
Outdoor unit model
MZ-COSMO18/O
Number of zones
2
Max indoor units
2 units[1]
Rated cooling capacity
18,000 BTU/hNon-Ducted Indoor Units[2]
Rated heating capacity
18,000 BTU/hNon-Ducted Indoor Units[2]
Voltage
230 V[1]
MCA
14.5 A[1]
Maximum fuse or breaker size
20 A[1]
Breaker needed
not published
SEER2
21 SEER2Non-Ducted Indoor Units[2]
EER2
12 EER2Non-Ducted Indoor Units[2]
HSPF2 (Region 4)
10 HSPF2Non-Ducted Indoor Units[2]
HSPF2 (Region 5)
Certified per indoor-unit combination, not per outdoor unit
COP
not published
COP at 47F
3.9 COP[1]
COP at 5F
2 COPNon-Ducted Indoor Units[2]
Minimum outdoor heating temperature
-22 F[1]
Minimum outdoor cooling temperature
-22 F[1]
Maximum outdoor temperature
118 F[1]
Indoor noise range
Indoor heads are selected separately on a multi-zone system
Outdoor noise rating
54 dBA[1]
Indoor weight
Indoor heads are selected separately on a multi-zone system
Outdoor weight
78.3 lb[1]
Refrigerant
R-32[2]
Refrigerant charge
not published
Manufacturer coverage
not published
Line-set size
1/4 in liquid / 3/8 in suction
Included line-set length
Indoor heads are selected separately on a multi-zone system
Maximum line-set length
328 ft[1]
Max line set per indoor
82 ft[1]
Maximum elevation difference
82 ft[1]
Max height between indoor units
82 ft[1]
Wi-Fi support
Indoor heads are selected separately on a multi-zone system
Energy Star status
ENERGY STAR certified[3]
AHRI certification number
215708456Non-Ducted Indoor Units[2]
Warranty
Standard: 5 yr parts / 5 yr compressor (published Cosmo warranty terms). TOSOT Direct Cosmo Multi-Zone pages list a 5-year standard warranty for both compressor and parts.
Install path
Professional install
Retail price
These TOSOT/Cosmo multi-zone systems are professional-install equipment, so we link to contractor quotes rather than a retail price.
Available retailers
not published
Manual links
AHRI public detail 215708456, ENERGY STAR exact AHRI rows 215708456, Cosmo MZ user manual, 18,000 BTU Multi-Zones Split System / MZ-C18 current product page, Lead-gen/no-retail audit for MZ-COSMO18/O, TOSOT 2025 brochure Cosmo Multi-Zone outdoor condenser specs
Specification sheet
TOSOT 2025 brochure Cosmo Multi-Zone outdoor condenser specs
Last sourced date
Jul 29, 2026

Electrical requirements

Show
Voltage
230 V[1]
Voltage range
208/230V[1]
Phase
1[1]
Frequency
60 Hz[1]
MCA
14.5 A[1]
Breaker needed
not published
Maximum breaker size
20 A[1]
Maximum fuse size
20 A[1]
Maximum cooling current
not published
Maximum heating current
not published
Manufacturer wire notes
not published

Installation considerations

Show
Liquid line
1/4 in[1]
Suction line
3/8 in[1]
Line connection type
not published
Precharged length
not published
Included line-set length
Indoor heads are selected separately on a multi-zone system
Maximum line-set length
328 ft[1]
Max line set per indoor
82 ft[1]
Max height between indoor units
82 ft[1]
Indoor dimensions
Indoor heads are selected separately on a multi-zone system
Outdoor dimensions
32.36 x 13.86 x 21.66 in[1]
Indoor weight
Indoor heads are selected separately on a multi-zone system
Outdoor weight
78.3 lb[1]
Drain size
not published

Related systems and guides

Frequently asked questions

Can I install the Cosmo Multi-Zone 2-Zone 18,000 BTU R-32 208/230V (MZ-COSMO18/O) myself, or do I need a pro?
Cosmo Multi-Zone 2-Zone 18,000 BTU R-32 208/230V (MZ-COSMO18/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 Multi-Zone 2-Zone 18,000 BTU R-32 208/230V (MZ-COSMO18/O) keep heating in a cold winter?
The manufacturer publishes 13,800 BTU/h of heating output at 5F. Rated heating operation extends down to -22 F. Certified heating efficiency is 10 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 Multi-Zone 2-Zone 18,000 BTU R-32 208/230V (MZ-COSMO18/O) need?
Published electrical requirements: 230 V voltage, 14.5 A minimum circuit ampacity, and 20 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 328 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 Multi-Zone 2-Zone 18,000 BTU R-32 208/230V (MZ-COSMO18/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 2025 brochure Cosmo Multi-Zone outdoor condenser specsSourced - manufacturer technical document

    Covers Frequency, electrical_spec.guaranteed_voltage_range, Maximum breaker size, Maximum fuse size, Minimum circuit ampacity, Phase and more

  2. Air-Conditioning, Heating, and Refrigeration Institute: AHRI Appendix M1 public detail for MZ-COSMO18/OSourced - AHRI directory

    Covers AHRI certification number, performance_spec.cold_climate_designation, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity and more

  3. ENERGY STAR: ENERGY STAR public certified air-source heat-pump rows for MZ-COSMO18/OSourced - Energy Star listing

    Covers performance_spec.energy_star_cold_climate, Energy Star status

  4. TOSOT Direct: TOSOT Direct Cosmo Multi-Zone product page warranty languageSourced - manufacturer product page

    Covers product_line.name, Legacy compressor warranty value, Legacy warranty value, Standard compressor warranty, Standard warranty conditions, Standard parts warranty and more

Last updated

Jul 29, 2026