MRCOOL / DIY 5th Gen Hyper Heat
MRCOOL DIY Hyper Heat 5th Gen 18,000 BTU (230V)
Model data is drawn from manufacturer, retailer, and certification sources. Missing specifications remain marked as not published.
1 zoneDIY installDIY-marketedCurrent
Data completeness: 98%
- Last verified
- Jul 20, 2026
SplitAtlas score
not yet rated - data incomplete
- no scoring run is available
1. Summary
The MRCOOL DIY Hyper Heat 18k is the strongest cold-climate unit in our DIY catalog: it holds its full 18,000 BTU/h of rated heating all the way down to 5F and operates to -22F, at an HSPF2 of 11 - performance that usually comes from a pro-installed Hyper-Heating system, in a unit you can install yourself with Quick Connect line sets.
Rated cooling
18,000BTU/hVerified - AHRI certificate
Rated heating
18,000BTU/hVerified - AHRI certificate
2. Best-fit use cases
A cold-climate home needing serious, self-installed heating for a larger room or open zone - where you want Hyper-Heating-class low-temperature output without booking a contractor, and 230V service is available.
3. Key specifications
- Manufacturer
- MRCOOL
- Brand
- MRCOOL
- Product line
- DIY 5th Gen Hyper Heat
- Model number
- DIY-18-HP-WMAH-230D25-O indoor / DIYHH-18-HP-C-230D25-O outdoor
- Indoor unit model
- DIY-18-HP-WMAH-230D25-O
- Outdoor unit model
- DIYHH-18-HP-C-230D25-O
- Number of zones
- 1
- Max indoor units
- not published
- Rated cooling capacity
- 18,000 BTU/hVerified - AHRI certificate
- Rated heating capacity
- 18,000 BTU/hVerified - AHRI certificate
- Voltage
- 208/230VVerified - manufacturer technical document
- MCA
- 19 AVerified - manufacturer technical document
- Maximum fuse or breaker size
- 25 AVerified - manufacturer technical document
- Breaker needed
- not published
- SEER2
- 21.2 SEER2Verified - AHRI certificate
- EER2
- 12.5 EER2Verified - AHRI certificate
- HSPF2 (Region 4)
- 11 HSPF2Verified - AHRI certificate
- HSPF2 (Region 5)
- 8.5 HSPF2Verified - manufacturer technical document
- COP
- not published
- COP at 47F
- not published
- COP at 5F
- 1.99 COPVerified - AHRI directory
- Minimum outdoor heating temperature
- -22 FVerified - manufacturer technical document
- Minimum outdoor cooling temperature
- -22 FVerified - manufacturer technical document
- Maximum outdoor temperature
- 122 FVerified - manufacturer technical document
- Indoor noise range
- 54.5 / 45 / 40 / 30.5 / 20.5 dB(A)Verified - manufacturer technical document
- Outdoor noise rating
- 58 dBAVerified - manufacturer technical document
- Indoor weight
- 35.49 lbVerified - manufacturer technical document
- Outdoor weight
- 99.87 lbVerified - manufacturer technical document
- Refrigerant
- R-454BVerified - manufacturer technical document
- Refrigerant charge
- 52.21 ozVerified - manufacturer technical document
- Manufacturer coverage
- 800 sq ftVerified - manufacturer technical document
- Line-set size
- 1/4 in liquid / 1/2 in suction
- Included line-set length
- 25 ftVerified - manufacturer technical document
- Maximum line-set length
- 75 ftVerified - manufacturer product page
- Max line set per indoor
- not published
- Maximum elevation difference
- not published
- Max height between indoor units
- not published
- Wi-Fi support
- supportedVerified - manufacturer technical document
- Energy Star status
- yesVerified - AHRI directory
- AHRI certification number
- 216032551Verified - AHRI certificate
- Warranty
- 5 years parts / 7 years compressor. Standard 5-year parts plus 7-year compressor warranty.
- DIY installation status
- DIY-marketed
- Retail price
- $3,173.00
- Installation type
- DIY install
- Available retailers
- HVACDirect
- Manual links
- AHRI certificate 216032551 for DIYHH-18-HP-C-230D25-O / DIY-18-HP-WMAH-230D25-O, AHRI public directory details for MRCOOL DIY Hyper Heat wall-mount pairings, MRCOOL DIY Hyper Heat Series Single Zone Installation and Owner's Manual, DIY 5th Gen - R454B - 18K Hyper Heat BTU 230V Condenser w/ 25ft Install Kit, MRCOOL DIY Hyper Heat 5th Gen performance specs, HVACDirect product page DIYHH-18-HP-WM-230D25-O, MRCOOL DIY Hyper Heat 5th Gen brochure/specifications, MRCOOL 5th Generation DIY Series Limited Warranty
- Specification sheet
- MRCOOL DIY Hyper Heat 5th Gen brochure/specifications
- Last verified date
- Jul 20, 2026
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Paid link
Check price at HVACDirect
$3,173 / Fresh price - checked Jul 20, 2026
4. Strengths
- Publishes 18,000 BTU/h heating at 5F - full rated capacity maintained in deep cold, which most heat pumps cannot claim.
- HSPF2 11 - high seasonal heating efficiency, and rated operation to -22F.
- DIY-installable (pre-charged Quick Connect); 5-year parts / 7-year compressor warranty that does not disclaim self-installation.
- R-454B refrigerant.
5. Weaknesses
- 230V with a 19 A minimum circuit ampacity and 25 A max fuse - a real electrical load; confirm your panel before planning a DIY install.
- SEER2 21.2 - cooling efficiency trails the 12k; this unit is tuned for heating, so mild-climate coolers gain little from it.
- Highest price in the DIY single-zone line - you're paying for the cold-climate heating.
6. Climate suitability
- Minimum heating ambient
- -22 FVerified - manufacturer technical document
- Rated heating at 5F
- 18,000 BTU/hVerified - AHRI directory
- Rated heating at 17F
- 15,200 BTU/hVerified - AHRI directory
- Rated heating at 47F
- 18,000 BTU/hVerified - AHRI certificate
7. Electrical requirements
- Voltage
- not published
- Voltage range
- 208/230VVerified - manufacturer technical document
- Phase
- 1Verified - manufacturer technical document
- Frequency
- 60 HzVerified - manufacturer technical document
- MCA
- 19 AVerified - manufacturer technical document
- Breaker needed
- not published
- Maximum breaker size
- not published
- Maximum fuse size
- 25 AVerified - manufacturer technical document
- Maximum cooling current
- not published
- Maximum heating current
- not published
- Manufacturer wire notes
- not published
8. Installation considerations
- Liquid line
- 1/4 inVerified - manufacturer technical document
- Suction line
- 1/2 inVerified - manufacturer technical document
- Precharged length
- 25 ftVerified - manufacturer technical document
- Included line-set length
- 25 ftVerified - manufacturer technical document
- Maximum line-set length
- 75 ftVerified - manufacturer product page
- Max line set per indoor
- not published
- Max height between indoor units
- not published
- Indoor dimensions
- 42.52 in W x 13.19 in H x 8.9 in DVerified - manufacturer technical document
- Outdoor dimensions
- 35.04 in W x 26.5 in H x 13.46 in DVerified - manufacturer technical document
- Indoor weight
- 35.49 lbVerified - manufacturer technical document
- Outdoor weight
- 99.87 lbVerified - manufacturer technical document
- Drain size
- not published
9. Operating-cost estimate
not published
10. Comparable models
Frequently asked questions
- Can I install the MRCOOL DIY Hyper Heat 5th Gen 18,000 BTU (230V) myself, or do I need a pro?
- MRCOOL DIY Hyper Heat 5th Gen 18,000 BTU (230V) is sold as a DIY-installable system with a pre-charged 25 ft line set, so no refrigerant handling or vacuum pump is required for a standard install. The electrical circuit is the part that is not DIY: plan on a licensed electrician for the dedicated circuit, and check whether your local permit office requires a permit for the install.
- Will the MRCOOL DIY Hyper Heat 5th Gen 18,000 BTU (230V) keep heating in a cold winter?
- The manufacturer publishes 18,000 BTU/h of heating output at 5F. Rated heating operation extends down to -22 F. Certified heating efficiency is 11 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
- What electrical circuit does the MRCOOL DIY Hyper Heat 5th Gen 18,000 BTU (230V) need?
- Published electrical requirements: 208/230V voltage, 19 A minimum circuit ampacity, and 25 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
- How far can the outdoor unit be from the indoor head?
- The published maximum line-set length is 75 ft, and the included line set comes pre-charged for 25 ft. Longer runs than the included set allows typically mean added refrigerant and a pro visit, so measure the planned routing before ordering.
- What warranty does the MRCOOL DIY Hyper Heat 5th Gen 18,000 BTU (230V) carry?
- The manufacturer publishes 5 years parts coverage and 7 years compressor coverage. Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.
11. Data sources
- MRCOOL: MRCOOL DIY Hyper Heat 5th Gen brochure/specificationsVerified - manufacturer technical document
Covers Frequency, Maximum fuse size, Minimum circuit ampacity, Phase, Voltage range, Manufacturer coverage and more
- MRCOOL-hosted Dasen HVAC storefront: DIY 5th Gen - R454B - 18K Hyper Heat BTU 230V Condenser w/ 25ft Install KitVerified - manufacturer product page
Covers Maximum line-set length
- AHRI: AHRI certificate 216032551 for DIYHH-18-HP-C-230D25-O / DIY-18-HP-WMAH-230D25-OVerified - AHRI certificate
Covers AHRI certification number, Rated cooling capacity, EER2, Rated heating capacity, HSPF2 (Region 4), Rated heating at 47F and more
- AHRI: AHRI public directory details for MRCOOL DIY Hyper Heat wall-mount pairingsVerified - AHRI directory
Covers COP at 5F, Energy Star status, Rated heating at 17F, Rated heating at 5F
- MRCOOL: MRCOOL DIY Hyper Heat Series Single Zone Installation and Owner's ManualVerified - manufacturer technical document
Covers Minimum outdoor cooling temperature, Minimum outdoor heating temperature, Maximum outdoor temperature
- HVACDirect: HVACDirect product page DIYHH-18-HP-WM-230D25-OVerified - authorized distributor
Covers Retail price
- MRCOOL: MRCOOL 5th Generation DIY Series Limited WarrantyVerified - manufacturer technical document
Covers Compressor warranty, Parts warranty, Warranty notes
12. Last updated date
Jul 21, 2026