MRCOOL DIY® Select 18,000 BTU Mini-Split Complete System 230V – Single Zone, Up to 800 Sq. Ft. | DIYS-18-HP-230A11-O

MRCOOL® DIY® Select 18,000 BTU Mini-Split Complete System – Single Zone, 230V

The MRCOOL® DIY® Select 18,000 BTU Complete System is an affordable, all-in-one mini split solution for heating and cooling spaces up to 800 sq. ft. Everything you need is included — condenser, air handler, and an 11.5 ft. pre-charged QuickConnect® line set — for a fast, tool-free DIY installation. Note: this unit uses a 1/2" suction line and runs on 230V — a dedicated 230V circuit is required. Additional line set lengths (16 ft., 25 ft., 35 ft., and 50 ft.) are available separately up to a maximum of 75 ft.

Why Choose MRCOOL DIY® Select?

• Included 11.5 ft. QuickConnect® Line Set — Pre-charged with R-454B refrigerant for a fast, vacuum-free installation right out of the box.
• Inverter Technology — Variable-speed compressor continuously adjusts output to match your space’s exact demand, reducing energy use and maintaining consistent temperatures.
• Ultra-Quiet Operation — As low as 18.5 dB(A) in sleep mode — ideal for bedrooms and home offices.
• Smart Connectivity — Control via the MRCOOL Comfort app (iOS & Android), or hands-free with Amazon Alexa or Google Assistant.
• Eco-Friendly R-454B Refrigerant — Lower Global Warming Potential (GWP) than R-410A for better efficiency and a reduced environmental footprint.
• Extendable Line Set — Additional lengths available separately (16 ft., 25 ft., 35 ft., 50 ft.) up to a maximum of 75 ft.
• Covers Large Spaces — 18,000 BTU heating capacity handles rooms up to 800 sq. ft. with ease.

Product Overview

• 🏠 Zones: 1
• 📐 Coverage: Up to 800 sq. ft.
• 🔧 Installation: DIY — No Professional Required
• ⚡ Voltage: 208-230V (dedicated circuit required)
• 🔇 Noise Level: As low as 18.5 dB(A) in sleep mode
• 🧄 Refrigerant: R-454B
• ⚠️ Note: Uses 1/2" suction line — verify line set compatibility before ordering

What’s in the Box

• ✅ 18,000 BTU outdoor condenser
• ✅ Indoor wall-mount air handler
• ✅ 11.5 ft. pre-charged QuickConnect® line set (1/4" x 1/2", R-454B)
• ✅ Remote control

Specifications & Dimensions

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’s the difference between the DIY Select and the DIY 5th Gen?
The DIY Select is MRCOOL’s entry-level line — more affordable and includes a shorter 11.5 ft. line set. The 5th Gen is the premium line with higher SEER2 ratings, longer line sets, a 7-year compressor warranty, and Energy Star certification. The Select is ideal for budget-conscious buyers; the 5th Gen is better for long-term efficiency and larger spaces.

Does this unit require special wiring?
Yes — the 18K DIY Select runs on 208-230V and requires a dedicated 230V circuit. Unlike the 9K and 12K Select models, this unit cannot plug into a standard 115V household outlet.

What size suction line does this unit use?
This unit uses a 1/2" suction line — larger than the 9K and 12K Select models which use 3/8". Make sure your line set is compatible before ordering.

Can I extend the line set beyond 11.5 ft.?
Yes — additional line set lengths (16 ft., 25 ft., 35 ft., and 50 ft.) are available separately, up to a maximum of 75 ft.

Is it Wi-Fi compatible?
Yes. Control your system from anywhere using the MRCOOL Comfort app on iOS or Android. It also works with Amazon Alexa and Google Assistant for hands-free voice control.

What is the warranty?
The DIY Select is backed by:

• 2-Year Compressor Warranty
• 1-Year Parts Warranty

Recommended BTU By Room Size

Note: Actual performance may vary depending on room insulation, ceiling height, number of windows, climate zone, and heat-generating appliances.