MRCOOL DIY 18K Hyper Heat Mini Split System – 5th Gen, -22°F Heating, 21.2 SEER2, Pre-Charged DIY Line Set
MRCOOL DIY 18K Hyper Heat Mini Split System – 5th Gen, -22°F Heating, 21.2 SEER2, Pre-Charged DIY Line Set
New for 2025 – True -22°F Hyper Heat Performance with DIY Installation
The MRCOOL® DIYHH-18 Hyper Heat 18K Mini Split is the first 5th Generation DIY system engineered for true cold-climate installs down to -22°F. This complete bundle includes the DIYHH-18 outdoor condenser and the DIY-18-HP-WMAH-230D25-O wall-mounted air handler, delivering powerful heating and cooling for spaces up to 800 sq. ft.
Unlike traditional mini split systems, the MRCOOL DIY series uses factory-sealed QuickConnect® pre-charged line sets filled with R-454B low-GWP refrigerant, requiring no vacuum pump, gauges, nitrogen, or HVAC certification. This system installs quickly, safely, and cleanly—designed specifically for homeowners.
What's Included
- DIYHH-18-HP-C-230D25-O — 18K Hyper Heat Outdoor Condenser
- DIY-18-HP-WMAH-230D25-O — 18K Wall-Mounted Air Handler
- DIY25-1412 — 25 ft Pre-Charged QuickConnect® Line Set
- DIYPRO® Cable
- Wireless Remote + Manuals + Mounting Hardware
ℹ️ Line Set Length Info
This system includes a standard 25 ft. line set. Extended line set options add an additional line set, couplers, and a longer control wire for installations requiring extra distance.
Condenser Specifications – DIYHH-18-HP-C-230D25-O
| Performance | |
|---|---|
| BTU Rating | 18,000 BTU Heating & Cooling |
| SEER2 | 21.2 |
| EER2 | 12.5 |
| HSPF2-4 | 11 |
| HSPF2-5 | 8.5 |
| Min Ambient Heat | -22°F |
| Operating Temp Range | -22°F to 122F |
| Compressor | Inverter Rotary |
| CFM | 1765.8 |
| Electrical | |
| Voltage | 208/230V |
| Phase | 1 |
| Cycle | 60Hz |
| Min Circuit Ampacity | 19A |
| Max Fuse | 25A |
| Refrigeration | |
| Refrigerant | R-454B |
| Factory Charge Volume | 52.21 oz |
| Line Set | 25 ft Pre-Charged QuickConnect® |
| Max Supported Line Length | 75 ft |
| Liquid Line | 1/4 in |
| Suction Line | 1/2 in |
| Metering Device | Electronic Expansion Valve (EEV) |
| Noise | |
| Condenser Noise | 58 dBA |
| Dimensions | |
| Net Dimensions | 35.04” W × 26.5” H × 13.46” D |
| Net Weight | 99.87 lbs |
| Gross Dimensions | 40.55” W × 29.53” H × 18.11” D |
| Gross Weight | 120.15 lbs |
Wall Mount Air Handler – DIY-18-HP-WMAH-230D25-O
| Performance | |
|---|---|
| BTU Capacity | 18,000 BTU |
| Coverage Area | Up to 800 sq. ft. |
| Fan Speeds | 5-Speed |
| Quiet Mode | Yes |
| Noise Level | 19 dBA (Low) – 54.5 dBA (High) |
| Dimensions | |
| Net Dimensions | 42.52” W × 13.19” H × 8.9” D |
| Net Weight | 35.49 lbs |
| Gross Dimensions | 46.73” W × 14.29” H × 17.68” D |
| Gross Weight | 49.6 lbs |
Smart Features
- MRCOOL SmartHVAC App
- iOS + Android Compatible
- Alexa & Google Assistant Voice Control
- Wireless Remote Included
Warranty
- 7-Year Compressor Warranty (Registered)
- 5-Year Parts Warranty (Registered)
- Extended Limited Lifetime with MRCOOL Care
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MRCOOL DIY 18K Hyper Heat Mini Split System – 5th Gen, -22°F Heating, 21.2 SEER2, Pre-Charged DIY Line Set
New for 2025 – True -22°F Hyper Heat Performance with DIY Installation
The MRCOOL® DIYHH-18 Hyper Heat 18K Mini Split is the first 5th Generation DIY system engineered for true cold-climate installs down to -22°F. This complete bundle includes the DIYHH-18 outdoor condenser and the DIY-18-HP-WMAH-230D25-O wall-mounted air handler, delivering powerful heating and cooling for spaces up to 800 sq. ft.
Unlike traditional mini split systems, the MRCOOL DIY series uses factory-sealed QuickConnect® pre-charged line sets filled with R-454B low-GWP refrigerant, requiring no vacuum pump, gauges, nitrogen, or HVAC certification. This system installs quickly, safely, and cleanly—designed specifically for homeowners.
What's Included
- DIYHH-18-HP-C-230D25-O — 18K Hyper Heat Outdoor Condenser
- DIY-18-HP-WMAH-230D25-O — 18K Wall-Mounted Air Handler
- DIY25-1412 — 25 ft Pre-Charged QuickConnect® Line Set
- DIYPRO® Cable
- Wireless Remote + Manuals + Mounting Hardware
ℹ️ Line Set Length Info
This system includes a standard 25 ft. line set. Extended line set options add an additional line set, couplers, and a longer control wire for installations requiring extra distance.
Condenser Specifications – DIYHH-18-HP-C-230D25-O
| Performance | |
|---|---|
| BTU Rating | 18,000 BTU Heating & Cooling |
| SEER2 | 21.2 |
| EER2 | 12.5 |
| HSPF2-4 | 11 |
| HSPF2-5 | 8.5 |
| Min Ambient Heat | -22°F |
| Operating Temp Range | -22°F to 122F |
| Compressor | Inverter Rotary |
| CFM | 1765.8 |
| Electrical | |
| Voltage | 208/230V |
| Phase | 1 |
| Cycle | 60Hz |
| Min Circuit Ampacity | 19A |
| Max Fuse | 25A |
| Refrigeration | |
| Refrigerant | R-454B |
| Factory Charge Volume | 52.21 oz |
| Line Set | 25 ft Pre-Charged QuickConnect® |
| Max Supported Line Length | 75 ft |
| Liquid Line | 1/4 in |
| Suction Line | 1/2 in |
| Metering Device | Electronic Expansion Valve (EEV) |
| Noise | |
| Condenser Noise | 58 dBA |
| Dimensions | |
| Net Dimensions | 35.04” W × 26.5” H × 13.46” D |
| Net Weight | 99.87 lbs |
| Gross Dimensions | 40.55” W × 29.53” H × 18.11” D |
| Gross Weight | 120.15 lbs |
Wall Mount Air Handler – DIY-18-HP-WMAH-230D25-O
| Performance | |
|---|---|
| BTU Capacity | 18,000 BTU |
| Coverage Area | Up to 800 sq. ft. |
| Fan Speeds | 5-Speed |
| Quiet Mode | Yes |
| Noise Level | 19 dBA (Low) – 54.5 dBA (High) |
| Dimensions | |
| Net Dimensions | 42.52” W × 13.19” H × 8.9” D |
| Net Weight | 35.49 lbs |
| Gross Dimensions | 46.73” W × 14.29” H × 17.68” D |
| Gross Weight | 49.6 lbs |
Smart Features
- MRCOOL SmartHVAC App
- iOS + Android Compatible
- Alexa & Google Assistant Voice Control
- Wireless Remote Included
Warranty
- 7-Year Compressor Warranty (Registered)
- 5-Year Parts Warranty (Registered)
- Extended Limited Lifetime with MRCOOL Care
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
New for 2025 – True -22°F Hyper Heat Performance with DIY Installation
The MRCOOL® DIYHH-18 Hyper Heat 18K Mini Split is the first 5th Generation DIY system engineered for true cold-climate installs down to -22°F. This complete bundle includes the DIYHH-18 outdoor condenser and the DIY-18-HP-WMAH-230D25-O wall-mounted air handler, delivering powerful heating and cooling for spaces up to 800 sq. ft.
Unlike traditional mini split systems, the MRCOOL DIY series uses factory-sealed QuickConnect® pre-charged line sets filled with R-454B low-GWP refrigerant, requiring no vacuum pump, gauges, nitrogen, or HVAC certification. This system installs quickly, safely, and cleanly—designed specifically for homeowners.
What's Included
- DIYHH-18-HP-C-230D25-O — 18K Hyper Heat Outdoor Condenser
- DIY-18-HP-WMAH-230D25-O — 18K Wall-Mounted Air Handler
- DIY25-1412 — 25 ft Pre-Charged QuickConnect® Line Set
- DIYPRO® Cable
- Wireless Remote + Manuals + Mounting Hardware
ℹ️ Line Set Length Info
This system includes a standard 25 ft. line set. Extended line set options add an additional line set, couplers, and a longer control wire for installations requiring extra distance.
Condenser Specifications – DIYHH-18-HP-C-230D25-O
| Performance | |
|---|---|
| BTU Rating | 18,000 BTU Heating & Cooling |
| SEER2 | 21.2 |
| EER2 | 12.5 |
| HSPF2-4 | 11 |
| HSPF2-5 | 8.5 |
| Min Ambient Heat | -22°F |
| Operating Temp Range | -22°F to 122F |
| Compressor | Inverter Rotary |
| CFM | 1765.8 |
| Electrical | |
| Voltage | 208/230V |
| Phase | 1 |
| Cycle | 60Hz |
| Min Circuit Ampacity | 19A |
| Max Fuse | 25A |
| Refrigeration | |
| Refrigerant | R-454B |
| Factory Charge Volume | 52.21 oz |
| Line Set | 25 ft Pre-Charged QuickConnect® |
| Max Supported Line Length | 75 ft |
| Liquid Line | 1/4 in |
| Suction Line | 1/2 in |
| Metering Device | Electronic Expansion Valve (EEV) |
| Noise | |
| Condenser Noise | 58 dBA |
| Dimensions | |
| Net Dimensions | 35.04” W × 26.5” H × 13.46” D |
| Net Weight | 99.87 lbs |
| Gross Dimensions | 40.55” W × 29.53” H × 18.11” D |
| Gross Weight | 120.15 lbs |
Wall Mount Air Handler – DIY-18-HP-WMAH-230D25-O
| Performance | |
|---|---|
| BTU Capacity | 18,000 BTU |
| Coverage Area | Up to 800 sq. ft. |
| Fan Speeds | 5-Speed |
| Quiet Mode | Yes |
| Noise Level | 19 dBA (Low) – 54.5 dBA (High) |
| Dimensions | |
| Net Dimensions | 42.52” W × 13.19” H × 8.9” D |
| Net Weight | 35.49 lbs |
| Gross Dimensions | 46.73” W × 14.29” H × 17.68” D |
| Gross Weight | 49.6 lbs |
Smart Features
- MRCOOL SmartHVAC App
- iOS + Android Compatible
- Alexa & Google Assistant Voice Control
- Wireless Remote Included
Warranty
- 7-Year Compressor Warranty (Registered)
- 5-Year Parts Warranty (Registered)
- Extended Limited Lifetime with MRCOOL Care
