MRCOOL DIY® 5th Gen 2-Zone 27,000 BTU Mini-Split System 230V with Pre-Charged Line Sets – 9K+18K, Up to 1,100 Sq. Ft. | DIY-MULTI4-27HP230D-O

MRCOOL® DIY® 5th Gen 2-Zone 27,000 BTU Mini-Split System with Pre-Charged Line Sets – 9K+18K, 230V

The MRCOOL® DIY® 5th Gen 2-Zone 27,000 BTU System delivers independent heating and cooling to two rooms of different sizes — a 9K zone for spaces up to 350 sq. ft. and an 18K zone for spaces up to 750 sq. ft. — for a total of 1,100 sq. ft. from a single outdoor condenser. With a 23.0 SEER2 rating, Energy Star certification, and MRCOOL’s 7-year compressor warranty, this is an efficient, cost-effective solution for two-room comfort. Two pre-charged QuickConnect® line sets are included in your chosen length combination. Note: the 9K zone uses 3/8" suction line; the 18K zone uses 1/2" suction line.

Why Choose MRCOOL DIY® 5th Gen 2-Zone 27K (9K+18K)?

• Asymmetric Zone Coverage — Perfect for a bedroom + living room, office + master suite, or any combination of one smaller and one medium-large space.
• 23.0 SEER2 — Premium Efficiency — High-efficiency cooling with significant year-round energy savings.
• Energy Star Certified — May qualify for federal tax credits and utility rebates.
• One Outdoor Unit, Two Rooms — A single 27K condenser powers both zones, saving outdoor space and installation cost vs. two separate single-zone systems.
• Line Sets Included — Two pre-charged QuickConnect® line sets in your chosen length combination. Select your lengths above before adding to cart.
• True DIY Installation — No HVAC license required. Pre-charged line sets make installation vacuum-free.
• Independent Zone Control — Each air handler operates independently with its own temperature setting.
• Operates to -13°F — Reliable heating in cold climates.
• Gold Fin® Coil Protection — Superior corrosion resistance, ideal for coastal homes and harsh climates.
• Smart Connectivity — Control each zone via 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 — Energy Star Certified, AHRI Certified, UL Listed, ETL Listed.

System Overview

• 🏠 Zones: 2
• 📐 Total Coverage: Up to 1,100 sq. ft.
• 📐 Zone 1: Up to 350 sq. ft. (9K air handler)
• 📐 Zone 2: Up to 750 sq. ft. (18K air handler)
• 🔧 Installation: DIY — No Professional Required
• ⚡ Voltage: 208-230V
• 📦 Line Sets: Included — select your length combination above
• 🌿 Energy Star Certified — May qualify for federal tax credits & utility rebates
• 🧄 Refrigerant: R-454B
• ⚠️ Note: 9K zone uses 3/8" suction line; 18K zone uses 1/2" suction line

What’s in the Box

• ✅ 1x 27,000 BTU outdoor condenser (DIY-MULTI4-27HP230D-O)
• ✅ 1x 9,000 BTU wall-mount air handler (DIY-09-HP-WMAH-230D25-O)
• ✅ 1x 18,000 BTU wall-mount air handler (DIY-18-HP-WMAH-230D25-O)
• ✅ 2x pre-charged QuickConnect® line sets in your selected lengths

Line Set Length Options

Select the combination that best matches the distance from your outdoor condenser to each indoor air handler. Measure before ordering — line sets cannot be shortened.

• 16 ft. + 16 ft.
• 25 ft. + 25 ft.
• 25 ft. + 50 ft.
• 35 ft. + 35 ft.
• 50 ft. + 50 ft.

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

Why does the condenser say 27K but the total zone capacity is also 27K?
The condenser is rated at 27K BTU to efficiently handle the combined 9K + 18K zone load. The condenser output (26K BTU cooling/heating) is slightly lower than the nameplate rating — this is normal for multi-zone systems and reflects real-world combined performance.

What’s a good use case for the 9K+18K configuration?
This setup works well for a bedroom (9K, up to 350 sq. ft.) paired with a living room, open-plan kitchen, or master suite (18K, up to 750 sq. ft.). Both zones are controlled independently.

How do I choose the right line set lengths?
Measure the distance from your outdoor condenser to each indoor air handler location. Add a few feet of slack. The 9K zone uses a 1/4" x 3/8" line set; the 18K zone uses a 1/4" x 1/2" line set. Both are included in your selected combination.

Can each zone be set to a different temperature?
Yes — each air handler operates independently. One zone can be cooling while the other is heating, or each can be set to different temperatures simultaneously.

Does this qualify for tax credits or rebates?
Yes — as an Energy Star certified system with a 23.0 SEER2 and 9.5 HSPF2-4, this unit may qualify for the federal Residential Clean Energy Credit or utility rebate programs. Check with your local utility provider and a tax professional for eligibility.

What is the warranty?
This system is backed by MRCOOL’s best-in-class warranty:

• 7-Year Compressor Warranty
• 5-Year Parts Warranty