What's in the box
- 1 × MRCOOL® DIY® 5th Gen 12K BTU Wall-Mounted Air Handler
- 1 × Wireless Remote Control
- Product Documentation
- DIY-friendly when installed as part of a compatible MRCOOL® DIY® 5th Gen system.
- This indoor air handler must be wall-mounted and connected to a compatible MRCOOL® outdoor condenser using approved Quick Connect® components.
- Electrical requirements, permits, and local building codes may vary.
- Professional electrical work may be required.
- Base Parts Warranty: 5 Years
- Base Compressor Warranty: 7 Years
- Eligible for the MRCOOL® Care Program when installed and registered as part of a qualifying MRCOOL® DIY® 5th Gen system.
Warranty coverage may depend on proper installation, compatible system pairing, product registration, and MRCOOL® warranty requirements. Please refer to the product warranty documentation for full terms, eligibility, and coverage details.
- Free U.S. curbside delivery within the Lower 48 States on qualifying orders
- Orders ship from U.S. warehouse locations
- Delivery times may vary by destination, product availability, and carrier scheduling
- Returns are accepted within 30 days for unused, uninstalled products that meet return eligibility requirements
- Approved returns may be subject to a restocking fee
MODEL: DIY-12-HP-WMAH-230D25-O
Comfort for Medium Rooms and Everyday Living Spaces.
Need efficient heating and cooling for a master bedroom, larger office, guest room, studio, or mid-size living area?
The MRCOOL® DIY® 5th Gen 12K BTU Wall-Mounted Air Handler is designed to deliver reliable comfort in rooms up to around 550 sq ft when paired with a compatible MRCOOL® DIY® 5th Gen multi-zone condenser.
This indoor air handler gives your room its own comfort zone, allowing you to control temperature, airflow, quiet mode, fan-only operation, dry mode, and smart settings from the included remote or through app-based control.
Built for MRCOOL® DIY® 5th Gen multi-zone systems, this 230V wall-mounted air handler features a clean white design, reusable filter, Follow Me® comfort sensing, WiFi compatibility, and smart-home control through Amazon Alexa and Google Assistant.
Smart. Efficient. Flexible. Built for everyday room comfort.
Why You’ll Love It
✅ 12K BTU wall-mounted air handler
✅ Ideal for rooms up to around 550 sq ft
✅ Designed for compatible MRCOOL® DIY® 5th Gen multi-zone systems
✅ Clean white wall-mounted design
✅ WiFi and app compatible
✅ Works with Amazon Alexa and Google Assistant
✅ Follow Me® comfort sensing
✅ Quiet Mode for lower sound comfort
✅ Auto Cool and Fan Only options
✅ Reusable filter
✅ Remote control included
✅ DIYPRO® cable compatible
✅ 5-Year Parts / 7-Year Compressor base warranty coverage when used as part of an eligible system
Best For
Master Bedrooms • Larger Bedrooms • Home Offices • Guest Rooms • Studios • Mid-Size Living Areas • Multi-Zone Mini-Split Systems • MRCOOL® DIY® 5th Gen Installations
What You Need for a Complete System
This product is an indoor air handler only.
For full heating and cooling performance, this air handler must be paired with compatible MRCOOL® DIY® 5th Gen multi-zone equipment.
Required for a complete system:
- MRCOOL® DIY® 5th Gen Multi-Zone Condenser — powers the system and connects multiple indoor zones.
- MRCOOL® Quick Connect® Pre-Charged Line Set — connects the indoor air handler to the outdoor condenser.
- DIYPRO® Cable — supports communication between the indoor air handler and outdoor condenser.
Wireless Remote Control — included with the air handler for room-by-room comfort control.
Optional accessories:
- MRCOOL® Wall Mount Bracket
- Additional Quick Connect® Line Sets
- Coupler Kits, if line set extension is required
Important: This air handler is not a stand-alone unit. It requires a compatible MRCOOL® DIY® 5th Gen multi-zone condenser for operation.
Compatibility note: This air handler is not compatible with MRCOOL® 3rd or 4th Generation systems.
| Product Type | Air Handler |
| Series | DIY® 5th Gen |
| BTU Size | 12K BTU |
| Voltage | 230V |
| Mount Type | Wall Mounted |
| Coverage | 550 sq ft |
| Model | DIY-12-HP-WMAH-230D25-O |
| Brand | MRCOOL® |
| System Type | Multi-Zone |
| Unit Type | Indoor Unit |
| Color | White |
| Phase | 1 Phase |
| Cycle | 60Hz |
| Full Voltage | 208/230V |
| Oscillation | Yes |
| Filter Type | Reusable |
| Quiet Mode | Yes |
| Auto Cool | Yes |
| Fan Only | Yes |
| WiFi Control | Yes |
| App Control | Yes |
| iOS Support | Yes |
| Android Support | Yes |
| Voice Control | Alexa / Google |
| Remote Control | Included |
| Aux Heater | No |
| Heat Kit | No |
| Batteries | Yes |
| Electronics | Yes |
| Chemicals | Yes |
| Aerosol | Yes |
| Gas Content | Yes |
| Prop 65 | Yes |
| UL Listed | Yes |
| ETL Listed | Yes |
| AHRI Certified | Yes |
| Intertek Listed | 5031495 |
| Base Warranty | 5-Year Parts / 7-Year Compressor |
| Net Dimensions | 31.57" W × 11.63" H × 7.44" D |
| Net Weight | 24.47 lb |
| Gross Dimensions | 36.02" W × 14.37" H × 16.34" D |
| Gross Weight | 35.05 lb |
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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