MRCOOL DIY® 5th Gen 18,000 BTU OuttaSight® Ceiling Cassette Air Handler 230V – Single Zone, Up to 750 Sq. Ft. | DIYCASSETTE18HP-230D25-O
Couldn't load pickup availability
MRCOOL® DIY® 5th Gen 18,000 BTU OuttaSight® Ceiling Cassette Air Handler – Single Zone, 230V
The MRCOOL® DIY® 5th Gen 18,000 BTU OuttaSight® Ceiling Cassette is a powerful, flush-mounted indoor unit designed for heating and cooling spaces from 501 to 750 sq. ft. Unlike traditional wall-mount units, this ceiling cassette installs discreetly between standard 16" ceiling joists — ideal for new construction, open-plan spaces, and retrofit projects where wall space is limited. Note: this unit uses a 1/2" suction line — ensure your line set and condenser are compatible before ordering.
Why Choose MRCOOL DIY® OuttaSight® Ceiling Cassette?
- Ceiling-Mounted, Out of Sight — Installs flush between standard 16" ceiling joists (including pre-manufactured I-joists) for a clean, unobtrusive look.
- Ideal for New Construction & Retrofits — No wall space required. Perfect for open-plan rooms, garages, sunrooms, and commercial spaces.
- America’s #1 DIY Mini Split — The most trusted DIY mini split brand in the nation, built for quick setup and long-term reliability.
- QuickConnect® Compatible — Works with MRCOOL pre-charged QuickConnect® line sets for a fast, vacuum-free installation — no special tools needed.
- Eco-Friendly R-454B Refrigerant — Lower Global Warming Potential (GWP) than R-410A for better efficiency and a reduced environmental footprint.
- Ultra-Quiet Operation — As low as 26 dB(A) on silent mode — barely audible.
- High Heating Output — 22,700 BTU heating capacity for reliable warmth even in larger spaces.
- Advanced Filtration — Improves indoor air quality with built-in filtration; Elevation function allows easy filter access for maintenance.
- Multiple Wireless Control Options — Control via included remote, the SmartHVAC app (iOS & Android), or hands-free with Amazon Alexa or Google Assistant.
- Best-in-Class Warranty — 7-year compressor warranty + 5-year parts warranty.
- Certified Excellence — UL Listed, ETL Listed, AHRI Certified.
Product Overview
- 🏠 Zones: 1
- 📐 Coverage: 501–750 sq. ft.
- 🔧 Installation: DIY — Ceiling-Mounted, No Professional Required
- 💨 Airflow Direction: 1-Way
- ⚡ Voltage: 208-230V
- 🔇 Noise Level: As low as 26 dB(A) on silent mode
- ⭐ Certification: UL Listed, ETL Listed, AHRI Certified
- 🧄 Refrigerant: R-454B
- ⚠️ Note: Uses 1/2" suction line — verify condenser and line set compatibility before ordering
Specifications & Dimensions
| Capacity & Performance | |
|---|---|
| Cooling Capacity | 18,800 BTU |
| Heating Capacity | 22,700 BTU |
| Coverage Area | 501–750 sq. ft. |
| Air Flow – Turbo | 400 CFM |
| Air Flow – High | 352 CFM |
| Air Flow – Medium | 300 CFM |
| Air Flow – Low | 207 CFM |
| Air Flow – Silent | 207 CFM |
| Noise – Turbo | 44.0 dB(A) |
| Noise – High | 44.0 dB(A) |
| Noise – Medium | 41.5 dB(A) |
| Noise – Low | 31.0 dB(A) |
| Noise – Silent | 26.0 dB(A) |
| Electrical Requirements | |
| Voltage | 208-230V |
| Phase | 1 |
| Cycle | 60 Hz |
| Max Fuse Breaker | 15A |
| Min Circuit Ampacity | 3A |
| Refrigerant & Piping | |
| Refrigerant Type | R-454B |
| Liquid Line Size | 1/4" |
| Suction Line Size | 1/2" |
| Dimensions & Weight | |
| Dimensions | 50.31" W x 13.19" D x 8.98" H |
| Mount Type | Ceiling |
| Weight | 45 lbs |
| Features | |
| Airflow Direction | 1-Way |
| Fan Only Option | Yes |
| Quiet Mode | Yes |
| Auto Cool | Yes |
| WiFi Compatibility | Yes |
| App Compatibility | Yes |
| Works with iOS | Yes |
| Works with Android | Yes |
| Remote Control Included | Yes |
| Certifications & Warranty | |
| Certifications | UL Listed, ETL Listed, AHRI Certified |
| Parts Warranty | 5 Years |
| Compressor Warranty | 7 Years |
Shipping & Returns
🚚 Free Curbside Delivery
All MRCOOL orders ship free via FedEx Ground, FedEx Freight, or an equivalent trusted carrier. Delivery is curbside only — please arrange assistance in advance as carriers are not able to bring items inside your home.
Tracking & Delivery
Tracking information is typically provided within 3–5 business days of your order. Once received, please allow 1–2 business days for tracking details to update.
↩️ Return Policy
30-Day Return Window
Returns must be requested within 30 days of your delivery date. We are unable to accept return requests after this period.
Return Conditions
To qualify for a return, items must be unused and uninstalled, and in original packaging including box and pallet.
Restocking Fee
A 35% restocking fee applies to all approved returns.
📄 View Full Shipping Policy | 📄 View Full Return & Refund Policy
Frequently Asked Questions
What condenser is compatible with this cassette?
This ceiling cassette is compatible with MRCOOL DIY® 5th Gen single-zone or multi-zone condensers rated for 18,000 BTU. Important: this unit uses a 1/2" suction line — ensure your condenser and line set support 1/2" connections before ordering.
Does it fit between standard ceiling joists?
Yes — the OuttaSight® cassette is designed to fit between standard 16" ceiling joists, including pre-manufactured I-joists, for a flush, concealed installation.
Can I install it myself?
Yes. Use MRCOOL DIY® pre-charged QuickConnect® line sets for a vacuum-free installation. Ceiling installation may require basic carpentry skills. A licensed electrician is still recommended for the electrical hookup.
How quiet is it?
Very quiet — as low as 26 dB(A) on silent mode. Even on high, it runs at just 44 dB(A).
What is the warranty?
This cassette is backed by MRCOOL’s best-in-class warranty:
- 7-Year Compressor Warranty
- 5-Year Parts Warranty
Recommended BTU By Room Size
| BTU Capacity | Recommended Room Size (Sq. Ft.) |
|---|---|
| 6,000 BTU | Up to 150 sq. ft. |
| 9,000 BTU | 151–350 sq. ft. |
| 12,000 BTU | 351–500 sq. ft. |
| 18,000 BTU ← You Are Here | 501–750 sq. ft. |
| 24,000 BTU | 751–1,000 sq. ft. |
| 36,000 BTU | 1,001–1,500 sq. ft. |
Note: Actual performance may vary depending on room insulation, ceiling height, number of windows, climate zone, and heat-generating appliances.
