What's in the box
- MRCOOL® 24K DIY® 5th Gen Mini-Split Air Handler
- 25ft DIYPro™ Communication Cable
- Wireless Remote Control
- Installation Accessories
- MRCOOL® Warranty
Free curbside shipping on eligible MRCOOL® systems across the continental U.S. Most products ship in 3–5 business days and arrive in 4–10 days, depending on your location. Freight carriers will call to schedule delivery.
Returns accepted within 30 days on new, unopened items in original packaging. A restocking fee of up to 35% may apply for HVAC equipment — we’ll always confirm before issuing a return authorization.
Each MRCOOL® system is backed by manufacturer warranty coverage as defined by product and model — typically 5–10 years on major components. Register your system after installation to activate full coverage.
Need help with sizing, voltage or compatibility? Email support@coolheatdirect.com — our U.S. team replies within one business day.
Manuals & documents
MODEL: DIY-24-HP-WMAH-230D25-O
Heavy-Duty, High-Capacity Comfort for Spaces up to 1,000 sq. ft.
The MRCOOL® 24k BTU DIY® 5th Generation Mini-Split Air Handler delivers serious heating and cooling power with whisper-quiet, energy-efficient operation — perfect for large open-concept living rooms, basements, bonus rooms, workshops, or oversized master bedrooms up to 1,000 sq. ft.
Designed for fully DIY-friendly installation, this air handler pairs easily with your MRCOOL® DIY® 5th Gen Multi-Zone Condenser via a pre-charged 25-foot Quick Connect® line set with eco-friendly R-454B refrigerant. No vacuum pump, no gauges, no expensive HVAC installer.
Control your comfort with ease using the SmartHVAC® app, Amazon Alexa, Google Assistant, and the included wireless remote. Thanks to Follow Me® technology, your room stays perfectly adjusted to your exact location — delivering balanced, room-to-room temperature precision.
Built to last, this unit features a Gold Fin® corrosion-resistant coating and comes backed by one of the best warranties in the industry, ensuring long-term, reliable performance through every season.
Why You’ll Love It
✅ Perfect for Larger Spaces — Ideal for oversized bedrooms, open-plan living areas, finished basements, and large bonus rooms up to 1,000 sq. ft.
✅ Simple DIY Installation — Pre-charged Quick Connect® lines and included 25ft DIYPro™ Communication Cable mean no vacuuming, gauges, or HVAC tech needed.
✅ Smart-Home Compatible — Wi-Fi enabled for full control via the SmartHVAC® app, Alexa, or Google Assistant.
✅ Follow Me® Comfort Technology — Adjusts system output based on your exact location for personalized comfort.
✅ Ultra-Quiet Operation — Runs between 27 and 45 dBA for peaceful, unobtrusive performance.
✅ Gold Fin® Protection — Corrosion-resistant coating ensures long-lasting durability.
✅ Year-Round Performance — Cools down to 5°F and heats up to 86°F for dependable, all-season comfort.
✅ Industry-Leading Warranty — Limited Lifetime Compressor Warranty (with registration), 7-Year Compressor, and 5-Year Parts Warranty.
What’s Included:
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MRCOOL® 24K DIY® 5th Gen Mini-Split Air Handler
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25ft DIYPro™ Communication Cable
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Wireless Remote Control
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Installation Accessories
-
MRCOOL® Warranty
Questions, answered
Everything homeowners ask before buying a MRCOOL® system.
Installation
Do I need an HVAC technician to install this?
No. MRCOOL® DIY systems are designed for homeowner installation. The pre-charged Quick Connect® line set means there's no refrigerant handling, no vacuum pump, and no special tools or license required.
How long does installation take?
Most single-zone systems go in within a few hours: mount the indoor air handler, set the outdoor condenser, connect the pre-charged line set, and power it on.
Do I need an electrician?
The system needs a dedicated circuit. Most homeowners have a licensed electrician add the breaker and disconnect — everything else you can do yourself.
Sizing & compatibility
What BTU size do I need?
As a rule of thumb: up to 400 sq ft → 9–12K BTU, 400–600 sq ft → 12–18K, 600–1,000 sq ft → 18–24K. Use the room-size guide above and factor in insulation, ceiling height and sun exposure.
Will it heat in winter?
Yes — these are heat pumps, so they heat and cool. Many MRCOOL® systems keep heating in sub-freezing temperatures; check each model's spec sheet for its low-temperature heating range.
115V or 230V — which do I need?
9K–12K units are usually 115V (standard outlet circuit); 18K and larger are typically 230V. The voltage is shown in the product options and specifications.
Warranty & support
What warranty is included?
MRCOOL® systems carry manufacturer warranty coverage — typically 5–10 years on major components when you register your system after installation.
How do I get help choosing or installing?
Email support@coolheatdirect.com — our U.S. team replies within one business day with sizing, voltage and compatibility help.
Shipping & returns
How fast does it ship?
Most products ship in 3–5 business days with free curbside delivery in the continental U.S. The freight carrier calls to schedule your delivery.
Can I return it?
Returns are accepted within 30 days on new, unopened items in original packaging. A restocking fee may apply to HVAC equipment — we always confirm before issuing a return authorization.

