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

(5F certified capacity: 76.7% of the 47F rating; -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

This TOSOT/Cosmo multi-zone system is sold through dealers, so its price comes as an installed quote that depends on your home. Get installation quotes to price it.

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

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.

Review methodology

Model context

Install path
This is professional-install equipment; price it with an installed quote.
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]
Certified 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
Depends on the indoor units you choose
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)
Varies by indoor-unit combination
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
Depends on the indoor units you choose
Outdoor noise rating
54 dBA[1]
Indoor weight
Depends on the indoor units you choose
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
Depends on the indoor units you choose
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
Depends on the indoor units you choose
Energy Star status
ENERGY STAR certified[3]
AHRI certification number
215708456Non-Ducted Indoor Units[2]
Warranty
Base: 5 yr parts / 5 yr compressor (published Cosmo warranty terms). Score uses Base.. TOSOT Direct Cosmo Multi-Zone pages list a 5-year standard warranty for both compressor and parts.
Install path
Professional install
Retail price
Installed quote only
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, 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
Depends on the indoor units you choose
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
Depends on the indoor units you choose
Outdoor dimensions
32.36 x 13.86 x 21.66 in[1]
Indoor weight
Depends on the indoor units you choose
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 AHRI/ENERGY STAR certification lists 13,800 BTU/h of heating capacity 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 from the outdoor unit to one indoor head is 82 ft. The combined piping limit across all heads is 328 ft. 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: 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

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, Base compressor warranty, Base warranty conditions, Base parts warranty and more

Last updated

Jul 29, 2026