Multi Zone Heating & Cooling Systems
GREE MULTI21 PLUS -20°C

Meet the Thermolux Gree Multi21+ series — flexible, inverter-driven ductless mini-split heat pumps built for multi-zone comfort across Greater Montreal, Laval, Longueuil, the South Shore and the North Shore. Spanning 18 000 to 42 000 BTU and supporting two to five zones per outdoor unit, Multi21+ systems balance capacity and control to match small apartments, multi-room homes and light-commercial spaces.

Designed for quiet, efficient operation, Thermolux Multi21+ leverages G10 inverter technology, eco-friendly R410A refrigerant and intelligent safeguards to fine-tune room-by-room temperatures while keeping energy costs in check. With dependable heating down to −20 °C and cooling from −18 °C to 48 °C, these compact split systems deliver year-round comfort in Quebec’s variable climate.

  • G10 inverter technology for precise temperature regulation and optimized power draw across multiple zones.
  • High efficiency with ratings up to 22 SEER and 11.5 HSPF to help reduce utility bills.
  • Low-noise performance with outdoor sound levels as low as 56 dB(A) for a calmer acoustic profile.
  • Smart reliability including auto-diagnostics, intelligent defrost, low-voltage start, washable filters and optional wired/remote controls.
  • Multi-zone flexibility supporting 2-, 3-, 4- and 5-zone configurations with R410A refrigerant and built-in Wi-Fi.

10-Year Warranty: Compressor and parts are covered for ten years, with optional 10-year labor available for added peace of mind.

SEER: 22 EER: 12.5 HSPF: 11.5 Sound Level: 58 Model: MULTI18HP230V1CO, MULTI24HP230V1CO, MULTI30HP230V1CO, MULTI36HP230V1CO, MULTI42HP230V1CO AHRI: 9958975, 9956591, 9956415, 9958976, 9956416, 9956592, 9956417, 9959010, 9956418, 9956593, 9959232, 9956594, 9959233, 9956595, 207251811 Minimum Operating Temperature: -20 Series: MULTI21+-COMPRESSOR Capacity: 18 000 BTU, 24 000 BTU, 30 000 BTU, 36 000 BTU, 42 000 BTU Refrigerant: R-410A Compressor Technology: Inverter Connectivity: Wi-Fi Technology Features: G10 inverter Rebate Programs: LogisVert Parts Warranty: 10 Labor Warranty: 10 Technology: G10 inverter technology, Self-diagnosis, Automatic voltage adaptation, Built-in WiFi, Energy-efficient R410A refrigerant Aesthetics: Discreet wall-mounted design, Compact indoor units, Uniform white finish, Integrated LED display Technical details: Energy Star certified, Built-in Wi-Fi, Efficiency up to 22 SEER, Heating down to -20 °C, Cooling range: -18 °C to 48 °C, G10 inverter technology, Multi-speed fan, Automatic louver control, Washable polymer air filters, Self-diagnosis, 220V power supply, R-410A refrigerant, Outdoor sound pressure: 58 dB(A) Coverage guide: 9 000 BTU — 300 – 500 sq. ft., 12 000 BTU — 400 – 650 sq. ft.

Efficiency

Up to
22 SEER
Up to
12.5 EER
Up to
11.5 HSPF
Ultra heat down to
-20 °C

BTU

18 000 BTU
600 – 1 000 sq. ft.
24 000 BTU
800 – 1 300 sq. ft.
30 000 BTU
1 100 – 1 600 sq. ft.
36 000 BTU
1 400 – 2 000 sq. ft.
42 000 BTU
1 950 – 2 300 sq. ft.

MODELS, CERTIFICATIONS AND COMPATIBLE COMBINATIONS

18 000 BTU MULTI18HP230V1CO

Certifications

  • Ducted indoor units AHRI 9956591
  • Non-ducted indoor units AHRI 9958975
  • Mixed ducted and non-ducted indoor units AHRI 9958976

Compatible indoor-unit combinations

Capacities shown in thousands of BTU.

2 indoor units

9 + 9 9 + 12
24 000 BTU MULTI24HP230V1CO

Certifications

  • Ducted indoor units AHRI 9956592
  • Non-ducted indoor units AHRI 9956415
  • Mixed ducted and non-ducted indoor units AHRI 9959010

Compatible indoor-unit combinations

Capacities shown in thousands of BTU.

2 indoor units

9 + 9 9 + 12 9 + 18 12 + 12 12 + 18 18 + 18

3 indoor units

9 + 9 + 9 9 + 9 + 12 9 + 9 + 18 9 + 12 + 12 12 + 12 + 12
30 000 BTU MULTI30HP230V1CO

Certifications

  • Ducted indoor units AHRI 9956593
  • Non-ducted indoor units AHRI 9956416
  • Mixed ducted and non-ducted indoor units AHRI 9959232

Compatible indoor-unit combinations

Capacities shown in thousands of BTU.

2 indoor units

9 + 9 9 + 12 9 + 18 9 + 24 12 + 12 12 + 18 12 + 24 18 + 18 18 + 24

3 indoor units

9 + 9 + 9 9 + 9 + 12 9 + 9 + 18 9 + 9 + 24 9 + 12 + 12 9 + 12 + 18 12 + 12 + 12 12 + 12 + 18

4 indoor units

9 + 9 + 9 + 9 9 + 9 + 9 + 12 9 + 9 + 12 + 12
36 000 BTU MULTI36HP230V1CO

Certifications

  • Ducted indoor units AHRI 9956594
  • Non-ducted indoor units AHRI 9956417
  • Mixed ducted and non-ducted indoor units AHRI 9959233

Compatible indoor-unit combinations

Capacities shown in thousands of BTU.

2 indoor units

9 + 9 9 + 12 9 + 18 9 + 24 12 + 12 12 + 18 12 + 24 18 + 18 18 + 24 24 + 24

3 indoor units

9 + 9 + 9 9 + 9 + 12 9 + 9 + 18 9 + 9 + 24 9 + 12 + 12 9 + 12 + 18 9 + 12 + 24 9 + 18 + 18 12 + 12 + 12 12 + 12 + 18 12 + 12 + 24 12 + 18 + 18

4 indoor units

9 + 9 + 9 + 9 9 + 9 + 9 + 12 9 + 9 + 9 + 18 9 + 9 + 12 + 12 9 + 9 + 12 + 18 9 + 12 + 12 + 12 12 + 12 + 12 + 12

5 indoor units

9 + 9 + 9 + 9 + 9 9 + 9 + 9 + 9 + 12
42 000 BTU MULTI42HP230V1CO

Certifications

  • Ducted indoor units AHRI 9956595
  • Non-ducted indoor units AHRI 9956418
  • Mixed ducted and non-ducted indoor units AHRI 207251811

Compatible indoor-unit combinations

Capacities shown in thousands of BTU.

2 indoor units

9 + 9 9 + 12 9 + 18 9 + 24 12 + 12 12 + 18 12 + 24 18 + 18 18 + 24 24 + 24

3 indoor units

9 + 9 + 9 9 + 9 + 12 9 + 9 + 18 9 + 9 + 24 9 + 12 + 12 9 + 12 + 18 9 + 12 + 24 9 + 18 + 18 12 + 12 + 12 12 + 12 + 18 12 + 12 + 24 12 + 18 + 18

4 indoor units

9 + 9 + 9 + 9 9 + 9 + 9 + 12 9 + 9 + 9 + 18 9 + 9 + 12 + 12 9 + 9 + 12 + 18 9 + 12 + 12 + 12 9 + 12 + 12 + 18 12 + 12 + 12 + 12

5 indoor units

9 + 9 + 9 + 9 + 9 9 + 9 + 9 + 9 + 12

Characteristics

PERFORMANCE
  • Quiet operation 58 dB
  • R-410A refrigerant
  • Inverter
  • Wi-Fi
  • G10 inverter
SUBSIDIES
  • LogisVert
Technology
  • G10 inverter technology
  • Self-diagnosis
  • Automatic voltage adaptation
  • Built-in WiFi
  • Energy-efficient R410A refrigerant
Aesthetics
  • Discreet wall-mounted design
  • Compact indoor units
  • Uniform white finish
  • Integrated LED display
Technical details
  • Energy Star certified
  • Built-in Wi-Fi
  • Efficiency up to 22 SEER
  • Heating down to -20 °C
  • Cooling range: -18 °C to 48 °C
  • G10 inverter technology
  • Multi-speed fan
  • Automatic louver control
  • Washable polymer air filters
  • Self-diagnosis
  • 220V power supply
  • R-410A refrigerant
  • Outdoor sound pressure: 58 dB(A)
Coverage guide
  • 9 000 BTU — 300 – 500 sq. ft.
  • 12 000 BTU — 400 – 650 sq. ft.

Warranty

  • 10 years parts limited warranty1
  • 10 years labor warranty1

Notes

  • 1 To the original owner, when product is used in an owner-occupied residence, he is covered a 10-year parts limited warranty.

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