MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v
Component — Not a Complete System
This is the outdoor unit only. To run, you also need a matching indoor air handler and a refrigerant line set. Looking for the complete system instead? Browse complete 18,000 BTU systems.
SKU DIY-MULTI3-18HP230D-O
With Incentives
Save up to $93323.9 SEER2 meets CEE Tier 2 (≥16). Find your state's rebate
MrCool DIY factory warranty — register after install to activate the full coverage tiers.
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Description
MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v
What's in the Box
Here's what you'll receive with your order
MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Spl...
As described
Key Specifications
23.9
SEER2 Rating
18000BTU
Cooling Capacity
208/230V
Voltage
60dBA
Noise Level
3
Zone Capacity
MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v — Model Details
What this specific model is sized for, how it installs, how it performs, and what it costs to run.
Room & Space Coverage — 18,000 BTU
The MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v delivers 18,000 BTU of cooling and heating capacity (1.5-ton class), sized for spaces up to 900 sq ft in standard 8-ft ceiling rooms with average insulation. At this capacity the unit handles medium primary rooms, master suites with attached bath, converted garages, and workshops. If your space includes a sunny west-facing wall or a finished bonus room above it, lean toward the upper end of the coverage range. As a multi-zone system this condenser supports up to 3 independent indoor heads, each with its own thermostat and mode — so bedrooms can cool while the living room heats, on one outdoor unit.
Efficiency & Operating Cost
This unit is rated at 23.9 SEER2 and 13 EER2 at full load. SEER2 measures seasonal cooling efficiency — higher is better — and 23.9 puts this in the premium efficiency tier. For heating performance it carries a 10 HSPF2 rating, which translates to roughly 300–350% heating efficiency versus resistance electric — one kilowatt-hour of electricity moves three kWh of heat into the space at mild outdoor temperatures. Running the unit 8 hours a day at full load draws roughly 181 kWh/month — about $29/month at the US average $0.16/kWh residential rate. Real-world draw is usually 30–50% lower because inverter compressors modulate down most of the time. ENERGY STAR certification makes this SKU eligible for federal tax credits (25C in 2026, up to 30% / $2,000 for qualifying heat pumps) and most state/utility rebate programs — check your state page for specific amounts.
Power & Electrical Requirements
Power requirement: 208/230V 1-phase 60Hz (standard US residential 240V service). Minimum circuit ampacity is 16A with a maximum overcurrent protection of 20A. Wire the outdoor unit with 12 AWG copper on a dedicated 20A double-pole breaker (or single-pole at 120V), with a disconnect within sight of the condenser per NEC 440.14.
Install Difficulty — DIY-Friendly
This DIY 5th gen Multi-Zone Mini-splits system ships with a pre-charged Quick Connect line set — no HVAC license, no vacuum pump, no refrigerant gauges. The pre-charged fittings use a hand-tightened mechanical seal that a homeowner completes in 15 minutes per connection. Typical install time from unboxing to first cool air is 4–8 hours for a single-head system. The system supports line set lengths up to 172.2ft; longer runs are available as accessory kits. Plan the shortest practical route — every 10ft of line set adds roughly 2% capacity loss. Ships with R-454B refrigerant. R-454B is the EPA 2025-compliant low-GWP replacement for R-410A, required for new-manufacture equipment — lower global-warming footprint without an efficiency penalty.
Sound Level & Comfort Features
Rated sound output is 60 dB(A) at full operation. Quiet mode caps fan speed and compressor rpm for an extra 2–3 dB drop in sound output.
Warranty & Certifications
Manufacturer warranty: 5 on parts, 7 on the compressor. AHRI certified and UL/ETL listed for North American electrical safety — required for most utility rebate and tax credit programs.
Product Details
We are thrilled to announce our new 5th Generation MRCOOL® DIY® 18k BTU Multi-Zone Ductless Mini Split Condenser, which is the best and most convenient way to get comfortable. You won’t need the services of an HVAC professional to install this unit, because it’s do-it-yourself! Achieving a SEER2 rating of 23.9 and an HSPF2-4 rating of 10, you can rest easy knowing this unit will help you save money as you chill. This condenser can also support up to three air handlers, meaning it can heat and cool three rooms that are a combined 750 square feet in size, making it a perfect option if you have spare bedrooms in need of heating and cooling. What makes this system different is our patented pre-charged Quick Connect® line sets filled with R-454B, an incredibly efficient and eco-friendly refrigerant. This switch from the previous refrigerant makes the system even more efficient and sustainable than before. The design of these innovative line sets allow you to install the system yourself, saving you time and money. These line sets are sold separately. This condenser is more than just a heating and cooling unit. When operating as a system, you will be able to experience total customization with the unit’s wealth of features. For example, you can integrate your system with Amazon Alexa or Google Home through the Smart HVAC app, allowing you to control your system with your voice and monitor its operation with the touch of a button. You can also set schedules, temperature ranges, and mode of operation through the app. The power of comfort is in your hands with this system. In the unlikely event that something happens to the system, we’ve got you covered. The DIY® series comes with one of the best warranties in the industry - a 7 year compressor warranty, a 5 year parts warranty, and a Limited Lifetime Replacement warranty with enrollment in the MRCOOL® Care Program. Give yourself the best comfort with the DIY®.
Specifications
| Cooling Capacity | 18,000 BTU |
| Heating Capacity | 18,000 BTU |
| SEER2 Rating | 23.9 |
| HSPF2 | 10 |
| Voltage | 208/230 V |
| Refrigerant | R-454B |
| Noise Level | 60 dBA |
| Zone Capacity | 3 zones |
| Max Line Set | 172.2 ft |
| EER2 | 13 |
| Tonnage | 1.5 Ton |
| Phase | 1 |
| Refrigerant Type | R-454B |
| Refrigerant Charge | 61.73 oz |
| Liquid Line Size | 1/4 |
| Suction Line Size | 3/8 |
Features
- Intertek listed 5031495
- Easy DIY installation
- Future-proof your investment with the included DIYPro® cable, eliminating the need for electrical conduit.
- Keep the included remote close by, and MRCOOL DIY®'s Follow Me® function will track the air temperature around you to ensure maximum comfort.
- The MRCOOL® Smart HVAC Controller® Module and App fully support Google Assistant & Amazon Alexa out of the box.
Frequently Asked Questions
Everything you need to know about this product
What size room will the MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v cool?
Can I install this myself without an HVAC license?
Is this unit eligible for the federal 25C tax credit?
What electrical circuit do I need for installation?
Can I add more indoor units later on this condenser?
How fast does HVACZAR ship this unit?
What if it arrives damaged or I change my mind?
What is the warranty on the MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v?
How long does shipping take?
What size room does 18,000 BTU cover?
What is the efficiency rating?
Do you offer returns?
How can I pay?
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Ships Nationwide — Shop by State
We deliver the MRCOOL® 18k DIY 5th Generation 3 Zone Multi-Zone Mini-Split Condenser 230v to all 50 states via FedEx, UPS, and truck freight. Each state page lists local rebate programs and utility incentives.