MRCOOL® DIY 4th Gen Multi-Zone 2-Zone Condenser
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-MULTI2-18HP230C
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MrCool DIY factory warranty — register after install to activate the full coverage tiers.
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Description
MRCOOL® DIY 4th Gen Multi-Zone 2-Zone Condenser
What's in the Box
Here's what you'll receive with your order
MRCOOL® DIY 4th Gen Multi-Zone 2-Zone Condenser
As described
Key Specifications
21.2
SEER2 Rating
18000BTU
Cooling Capacity
208-230V
Voltage
59dBA
Noise Level
2
Zone Capacity
MRCOOL® DIY 4th Gen Multi-Zone 2-Zone Condenser — 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® DIY 4th Gen Multi-Zone 2-Zone Condenser delivers 18,000 BTU of cooling and heating capacity, 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 2 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 21.2 SEER2 and 12.5 EER2 at full load. SEER2 measures seasonal cooling efficiency — higher is better — and 21.2 puts this in the premium efficiency tier. Running the unit 8 hours a day at full load draws roughly 204 kWh/month — about $33/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.
Cold & Hot Weather Operating Range
This system produces rated heating capacity down to -1375.2°F ambient, putting it in hyper-heat territory suitable for northern climates where ducted gas is the usual backup. On the cooling side the compressor runs down to 5122°F outdoor ambient, useful for server rooms, grow rooms, and any space that needs year-round cooling. The inverter-driven compressor modulates between roughly 30% and 110% of rated capacity instead of cycling on/off, which both extends runtime at extreme temperatures and holds tighter setpoints (±0.5°F) versus ±2–3°F on fixed-speed units.
Power & Electrical Requirements
Power requirement: 208-230V 1-phase 60Hz (standard US residential 240V service). Minimum circuit ampacity is 18A with a maximum overcurrent protection of 25A. Wire the outdoor unit with 10 AWG copper on a dedicated 25A 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 4th Gen Multi-Zone 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 123ft; 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-410A refrigerant. R-410A is a mature, widely-serviced refrigerant; service technicians and parts are available at any HVAC supply house.
Sound Level & Comfort Features
Rated sound output is 59 dB(A) at full operation.
Warranty & Certifications
When you register your unit within 60 days of purchase you get Limited Lifetime Compressor on the compressor through MrCool's registered warranty program. Unregistered coverage drops to 5-year Parts / 7-year Compressor — registration takes 3 minutes at mrcool.com and is the highest-ROI post-purchase step you can take.
What's in the Box & Compatibility
Ships as a Mini-Split.
Product Details
The 4th Generation MRCOOL® DIY 18K BTU 2-Zone Ductless Heat Pump Condenser is the latest in heat pump technology. This 2-zone condenser, when paired with select MrCool air handlers, is capable of producing an impressive 21 SEER efficiency rating. It also has the ability to heat even when temperatures drop to -13°F. It features robust construction which includes a Gold Fin Condenser coating so it is sure to withstand exposure to the elements. For added peace of mind, this is the only condenser on the market that comes with a limited lifetime compressor warranty. As a MrCool DIY product, this heat pump is designed specifically to be used with MrCool’s patented Pre-Charged Quick Connect Line Sets. These line sets come pre-charged with the precise amount of R-410A refrigerant. They are also equipped with quick connectors, so the line set can be connected to the condenser by the homeowner using only wrenches. This means the installation process can be performed without retaining the services of a certified technician. Let the 4th Generation MrCool DIY 18K BTU 2-Zone Ductless Heat Pump Condenser be the solution to your home’s heating and cooling needs.
Specifications
| Cooling Capacity | 18,000 BTU |
| Heating Capacity | 19,000 BTU |
| SEER2 Rating | 21.2 |
| Voltage | 208-230 V |
| Refrigerant | R-410A |
| Noise Level | 59 dBA |
| Zone Capacity | 2 zones |
| Max Line Set | 123 TOTAL ft |
| SEER Rating | 21 |
| EER2 | 12.5 |
| Airflow | 1764.71 CFM |
| Phase | 1 |
| Refrigerant Type | R-410A |
| Refrigerant Charge | 65.26 oz |
| Liquid Line Size | 1/4 |
| Suction Line Size | 1/2 |
Features
- Up to 21 SEER
- Gold Fin® condenser: corrosion resistant - live on the coast? Don't worry, our condenser is built to resist long term corrosion
- Energy Efficient DC Inverter
- R-410A environmentally friendly refrigerant
- Standard 7-year compressor/5-year parts warranty; register for limited lifetime compressor warranty
- Line sizes 1/4”, 1/2” & 3/8”, 5/8”
- Multi-Zone Condenser includes adapter for the 24K Air Handler (3/8", 5/8" Line Size) - see liquid line and suction line size columns
Frequently Asked Questions
Everything you need to know about this product
What size room will the MRCOOL® DIY 4th Gen Multi-Zone 2-Zone Condenser cool?
Can I install this myself without an HVAC license?
Is this unit eligible for the federal 25C tax credit?
How cold can it get outside before this heat pump stops heating?
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® DIY 4th Gen Multi-Zone 2-Zone Condenser?
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® DIY 4th Gen Multi-Zone 2-Zone Condenser to all 50 states via FedEx, UPS, and truck freight. Each state page lists local rebate programs and utility incentives.