Home / Mini Splits / DUET Series: one outdoor unit, two 9,000 BTU indoor units
Mini Splits / SKU MZR454B-DUETSERIES (outdoor) + 2x indoor 9K
18,000 BTU Dual Zone Mini Split System
DUET Series · one outdoor unit + two 9,000 BTU indoor heads · 24 SEER2 · 208/230V · WiFi + Alexa
- Free freight shipping, arrives on a pallet in one box
- 30-day money back, uninstalled, original condition
- 5-year compressor, 1-year parts
Overview
Looking for a dual zone mini split (also searched as a multi zone mini split or 18000 BTU mini split) that cools and heats two rooms from one outdoor unit? The Classic America / Vtronix DUET is a ductless mini split system with an 18,000 BTU outdoor unit and two 9,000 BTU indoor heads. It runs on 208/230V~/60Hz/1P, so plan a dedicated circuit with a licensed electrician before you buy.
Published efficiency for the non-ducted ENERGY STAR path is 24 SEER2 (ducted AHRI path lists 20 SEER2), with matching EER2 / HSPF2 on the spec sheet. Refrigerant is R454B (1700g). You get year-round comfort: 18,000 BTU cooling and 20,000 BTU heating, indoor sound about 30–43 dB per head, outdoor near 58 dB, plus Tuya WiFi, Amazon Alexa, and a physical remote in the box. Modes: Auto, Cool, Heat, Dry, and Fan.
The full kit ships free in one box (freight/pallet): outdoor unit, two indoor heads, and line-set hardware (Gas 3/8", Liquid 1/4"; max run 131 ft / precharge 49 ft). Classic America recommends a licensed HVAC install for refrigerant and electrical work—see the delivery & installation guide and install planner. Warranty is 5-year compressor / 1-year parts, with support from Miami Gardens, FL — call 1-800-349-4360 Ext. 204 (Mon–Fri, 10 AM–3 PM ET). Comparing one room vs two? Read single zone vs DUET or start at the mini splits category. Model MZR454B-DUETSERIES + 2× indoor 9K.
Key features
- Dual zone / multi zone — one 18k outdoor + two 9k indoor heads
- 18,000 BTU cool / 20,000 BTU heat
- 24 SEER2 (non-ducted ENERGY STAR) · 20 SEER2 (ducted AHRI) · ENERGY STAR + NEEP
- R454B · 208/230V~/60Hz/1P
- WiFi + Alexa · indoor 30–43 dB per head · outdoor ~58 dB
- Max line 131 ft / precharge 49 ft
- Free single-box shipping · 5yr compressor / 1yr parts
- Model MZR454B-DUETSERIES + 2× indoor 9K
What you need to install it
Licensed HVAC install is recommended. Read the delivery and installation guide.
Power
208/230V~/60Hz/1P
Indoor unit
32.28 x 7.68 x 12.05 (per 9K indoor head) in, 20.72 lb
Outdoor unit
36.5 x 14.96 x 27.52 in, 92.6 lb
Line set
Gas 3/8", Liquid 1/4"
Smart control, included
Every system ships with the app, voice control and a physical remote -- no add-on hub required.
WiFi App
Included
Tuya Smart
Voice Control
Included
Amazon Alexa
Remote
Included
In the box
Modes
5
Auto/Cool/Heat/Dry/Fan
Highlights
How it works, inside
A look at the parts inside every Classic America inverter heat pump.
What's inside the indoor unit
Filters, evaporator coil, cross-flow fan and the Wi-Fi control board, layer by layer.
Why an inverter compressor
It speeds up and slows down to hold your set temperature instead of cycling on and off.
One system, cooling and heating
The heat pump reverses its refrigerant flow to move heat out in summer and in during winter.
Performance, published in full
Cooling efficiency
24 (non ducted estar) / 20 (ducted ahri) SEER2, 13 (non ducted estar) / 10.5 (ducted ahri) EER2
Heating efficiency (HSPF2)
Region IV: 10.5 (non ducted estar) / 8.5 (ducted ahri), Region V: 9.5 (non ducted estar) / 7.33 (ducted ahri)
Certifications
ENERGY STAR non ducted, NEEP
Sound level, in context
Outdoor unit: 58 dB
Full specifications
| Model number | MZR454B-DUETSERIES (outdoor) + 2x indoor 9K |
| Cooling capacity | 18000 BTU |
| Heating capacity | 20000 BTU |
| Refrigerant | R454B, 1700g / 59.96oz |
| Max line length | 131 ft |
| Precharge line length | 49 ft |
Specifications per manufacturer spec sheet; fields not listed are not published.
Manuals and downloads
PDF. More documents on the manuals page.
FAQ
DUET 18,000 BTU mini split questions
What is a dual zone mini split, and is the DUET one?
A dual zone mini split (a type of multi zone mini split) uses one outdoor unit to serve two indoor heads. The Classic America / Vtronix DUET pairs an 18,000 BTU outdoor with two 9,000 BTU indoors so you can cool and heat two rooms independently. Compare options on the mini splits category or buying guide.
Is this the same as an 18,000 BTU mini split?
Yes for shopper intent: this is an 18000 BTU mini split outdoor capacity class, configured as a two-zone mini split system. Cooling is 18,000 BTU; heating is 20,000 BTU. Each indoor head is 9,000 BTU. Call 1-800-349-4360 Ext. 204 if you need help matching rooms.
What voltage and efficiency does the DUET use?
Power is 208/230V~/60Hz/1P. Published cooling efficiency is 24 SEER2 (non-ducted ENERGY STAR) / 20 SEER2 (ducted AHRI), with ENERGY STAR (non-ducted) and NEEP certifications. Refrigerant is R454B. See the energy savings tool and the full specs on this page.
Does this dual zone mini split also heat, and is WiFi included?
Yes. It is a heat-pump mini split system: cool and heat, with Auto / Cool / Heat / Dry / Fan. Tuya WiFi, Amazon Alexa, and a physical remote ship in the box—see the WiFi setup guide.
What's included, and is shipping free?
Outdoor unit, two indoor 9K heads, line-set hardware (Gas 3/8", Liquid 1/4"; max 131 ft / precharge 49 ft), WiFi/Alexa-ready controls, and remote ship free in one box (freight/pallet). See delivery & installation. Warranty: 5-year compressor, 1-year parts. Model MZR454B-DUETSERIES + 2× indoor 9K. Licensed HVAC install is recommended.
Smaller or larger room?
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