What's in the box
- MRCOOL® 12K DIY® 5th Gen Mini-Split Air Handler
- 25ft DIYPro™ Communication Cable
- Wireless Remote Control
- Installation Accessories
- MRCOOL® Warranty
- Free U.S. curbside delivery within the Lower 48 States on qualifying orders
- Orders ship from U.S. warehouses
- Delivery times may vary by location and carrier availability
- Returns accepted within 30 days for unused and uninstalled products
- Approved returns may be subject to a restocking fee
MODEL: DIY-12-HP-WMAH-115D25-O
Powerful, Ultra-Quiet Comfort for Spaces up to 550 sq. ft.
The MRCOOL® 12k BTU DIY® 5th Generation Mini-Split Air Handler offers efficient, whisper-quiet heating and cooling designed for easy, do-it-yourself installation. Perfect for bedrooms, offices, and medium-sized living spaces up to 550 sq. ft., this unit pairs seamlessly with your MRCOOL® DIY® 5th Gen Single-Zone or Multi-Zone Condenser.
Featuring a pre-charged 25-foot Quick Connect® line set filled with eco-friendly R-454B refrigerant, this system eliminates the need for vacuum pumps or professional HVAC installation. The included DIYPro™ Communication Cable replaces traditional electrical conduit, offering durability against outdoor elements.
Control your climate effortlessly with the SmartHVAC® app, Amazon Alexa, or Google Assistant voice commands. The built-in Follow Me® function senses the temperature at the wireless remote’s location, maintaining your ideal comfort level.
Built for long-lasting performance, the Gold Fin® corrosion-resistant coating makes this air handler ideal for coastal or humid environments. Enjoy dependable, efficient, year-round comfort backed by one of the industry’s leading warranties.
Why You’ll Love It
✅ Perfect for Medium Spaces — Ideal for bedrooms, home offices, and dens up to 550 sq. ft.
✅ True DIY Installation — Quick Connect® line sets and DIYPro™ cable make setup simple — no HVAC pro required
✅ Smart-Home Ready — Wi-Fi enabled, compatible with SmartHVAC® app, Alexa, and Google Assistant
✅ Follow Me® Personal Comfort — Wireless remote tracks your location to deliver customized comfort
✅ Ultra-Quiet Operation — Peaceful performance as low as 18 dBA
✅ Gold Fin® Protection — Anti-corrosion coating ensures durability in tough climates
✅ All-Season Heating & Cooling — Operates from 5°F to 86°F, delivering comfort year-round
✅ Industry-Leading Warranty — Limited Lifetime Compressor Warranty (with registration), 7-Year Compressor, 5-Year Parts
What You Need for a Complete System
For full heating and cooling performance, pair this indoor air handler with:
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MRCOOL® DIY® 5th Gen Single-Zone Condenser (115V Compatible)
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MRCOOL® Quick Connect® Pre-Charged Line Set (25ft included)
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DIYPro™ Communication Cable (25ft included)
Optional Accessories:
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MRCOOL® Wall Mount Bracket
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Additional Quick Connect® Line Sets (for extended runs)
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Coupler Kits (for line set extensions)
Important:
This air handler requires connection to a compatible MRCOOL® DIY® 5th Gen Condenser. It is not compatible with 3rd or 4th Gen systems.
| Voltage | 115V |
| Phase | 1 |
| Cycle | 60 Hz |
| Mount Type | Wall-Mounted |
| Color | White |
| Max Coverage Area | Up to 550 sq. ft. |
| Oscillation | Yes |
| Filter Type | Reusable |
| Auxiliary Heater | Not Included |
| Fan Only Option | Yes |
| Quiet Mode | Yes |
| Auto Cool | Yes |
| Wi-Fi Enabled | Yes |
| App Compatibility | iOS & Android |
| Remote Control Included | Yes |
| Batteries Included | Yes |
| UL/ETL Listed | Yes |
| AHRI Certified | Yes |
| Warranty | Lifetime Limited*, 7-Year Compressor, 5-Year Parts |
| Net Dimensions (WxHxD) | 31.57" x 11.69" x 7.44" |
| Gross Dimensions (WxHxD) | 36.02" x 14.37" x 16.34" |
| Net Weight | 24.91 lbs |
| Gross Weight | 35.49 lbs |
| Contains Electronics / Chemicals / Compressed Gas | Yes |
| Proposition 65 Warning | Yes |
Questions, answered
Everything homeowners ask before buying a MRCOOL® system.
Installation
What installation requirements apply to this product?
Installation requirements vary by product type. Selected complete MRCOOL® DIY systems are designed for homeowner installation when fitted in line with the manufacturer’s instructions, local codes and permit requirements.
Central HVAC systems, including Universal®, VersaPro®, Central Ducted Hyper Heat and packaged systems, are intended for professional installation by a qualified HVAC contractor. Licensed electrical work may also be required.
Components, thermostats, controls, line sets and accessories should be installed according to their product documentation and compatibility requirements. Always review the product page, manufacturer guidance and warranty conditions before installation.
Will I need any additional parts, tools or professional services?
Additional requirements vary by product and installation. Tools, electrical materials, mounting hardware, connecting components or other installation supplies may be required unless specifically stated as included.
Review the product description, specifications, installation information and What’s Included section, where available, before ordering.
Where can I find product documents or installation instructions?
Available specifications, installation instructions, owner’s manuals and manufacturer documents are provided on the product page where applicable.
Some simple accessories may not have a separate installation manual. Contact our team if you need help locating documentation for a particular product or model.
Sizing & Compatibility
How do I confirm this product is compatible with my equipment?
Review the product type, model number, dimensions, voltage, capacity, refrigerant type, connection sizes and compatibility information shown on the product page, where applicable.
Components, thermostats, controls and accessories must be matched to compatible equipment. Contact our team before ordering if you are uncertain about compatibility.
What should I check before ordering?
Confirm the product name and model number, together with any relevant dimensions, voltage, capacity, refrigerant type, connections and installation requirements.
For replacement components and accessories, compare the product specifications with your existing equipment and the relevant manufacturer documentation before placing your order.
What is included with this product?
The supplied items are listed in the What’s Included section or product description, where applicable. Only the products, components and accessories specifically stated are included.
Electrical materials, mounting equipment, connecting components or other installation supplies may need to be purchased separately unless expressly stated otherwise.
Warranty & Support
What warranty coverage applies to this product?
Warranty coverage varies by product and model. Eligible MRCOOL® products are covered according to the manufacturer’s warranty terms, registration requirements and installation conditions.
Accessories and individual components may have different coverage. Cool Heat Direct can provide available warranty documentation and general guidance, while warranty eligibility and claim decisions are determined by the manufacturer.
How can I get help before ordering?
Email support@coolheatdirect.com with the product name or model number and details about your project or existing equipment.
For compatibility questions, include the model numbers of any products you intend to connect, control, replace or use together.
Support hours: Monday–Friday, 9 AM–6 PM ET.
Shipping & Returns
How will my order be shipped?
Free standard shipping is available on eligible orders to the Lower 48 states and Washington, D.C.
Orders are generally processed within 3–5 business days, followed by approximately 5–12 business days in transit. Delivery timing varies by product availability, destination and carrier scheduling.
Smaller products may ship by parcel carrier. Larger equipment may be delivered curbside by freight carrier. The carrier may contact you to arrange a delivery appointment.
Can I return this product?
Return requests may be submitted within 30 calendar days of delivery. Products must be new, unused and uninstalled and, where applicable, unpowered. They must also be complete and in their original manufacturer packaging. Prior written authorization is required.
For approved change-of-mind returns, incorrect sizing or customer ordering errors, the customer is responsible for return freight and a 15% restocking fee applies.
Verified damaged, defective, incorrect or incomplete orders are handled separately under our full policy.
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