What's in the box
- MRCOOL® 18K DIY® OuttaSight® 5th Gen Ceiling Cassette (230V)
- 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: DIYCASSETTE18HP-230D25-O
Powerful, Discreet Climate Control for Areas up to 800 sq. ft.
The MRCOOL® DIY® Series 5th Generation OuttaSight® 18K BTU 230V One-Way Ceiling Cassette delivers powerful, discreet comfort for spaces up to 800 sq. ft. Perfect for home offices, basements, and medium-to-large rooms, it fits neatly between standard 16" ceiling joists—including I-joists—for a flush, built-in look that preserves your room’s style while eliminating bulky wall units and messy ductwork.
Designed for easy DIY installation, it connects seamlessly to the MRCOOL® DIY® Quick Connect® line set, pre-charged with eco-friendly R-454B refrigerant. No vacuuming, special tools, or professional help needed—just install and enjoy premium comfort on your schedule.
Experience whisper-quiet operation (26–44 dBA), smart control via remote, app, Alexa, or Google Assistant, and even airflow with advanced swing technology. Built-in filtration improves air quality, while the Elevation function makes filter maintenance effortless. Backed by MRCOOL’s industry-leading warranty—including a Limited Lifetime Compressor Warranty—this system delivers reliable, energy-efficient comfort for years to come.
Why You’ll Love It
✅ Perfect for Larger Rooms — Efficiently heats and cools areas up to 800 sq. ft.
✅ True DIY Installation — Pre-charged Quick Connect® line sets and no-vacuum hookup required
✅ Low-Profile, Seamless Ceiling Fit — Installs between 16” joists for a discreet, built-in look
✅ Smart-Home Control — Fully compatible with the SmartHVAC® app, Alexa, and Google Assistant
✅ Follow Me® Comfort — Remote tracks the temperature at your location for personalized control
✅ Ultra-Quiet DC Inverter Operation — Runs as quietly as 26 dBA
✅ Advanced Filtration & Elevation Filter Access — Cleaner, healthier indoor air and easy filter maintenance
✅ All-Season Performance — Delivers both powerful heating and cooling
✅ Industry-Leading Warranty — Limited Lifetime Compressor Warranty (with registration), 7-Year Compressor Warranty, 5-Year Parts Warranty
What’s Included:
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MRCOOL® 18K DIY® OuttaSight® 5th Gen Ceiling Cassette (230V)
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Wireless Remote Control
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Installation Accessories
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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.
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