Worth Exploring｜MRCOOL DIY® 5th Gen E Star 9,000 BTU Single Zone Mini Split Complete System with 25ft. Line Set 115V, DIY-09-HP-WM-115D25-O

The MRCOOL DIY® 5th Generation 9,000 BTU Single Zone Mini Split System is a high-efficiency heating and cooling solution designed for simple DIY installation and year-round climate control. Engineered with advanced technology and built for durability, this system is ideal for small to mid-sized spaces up to 400 sq. ft., offering whisper-quiet operation, customizable comfort, and smart home compatibility.
Designed for Easy DIY Installation
Unlike traditional mini-split systems, this unit features a pre-charged 25-ft QuickConnect® Line Set, allowing for installation without special tools, vacuum pumps, or professional HVAC assistance. The DIYPRO® Cable ensures a secure, hassle-free electrical connection between the indoor and outdoor units, making setup accessible even for first-time installers.
Advanced Energy Efficiency & Cost Savings
With an impressive 23.6 SEER rating, the MRCOOL DIY® Mini Split is Energy Star certified, helping to lower electricity costs while reducing environmental impact. The variable-speed inverter compressor optimizes performance by adjusting output based on demand, ensuring maximum efficiency with minimal energy waste.
Smart Climate Control & Convenience

Multi-Platform Smart Integration: Control your system remotely using the MRCOOL SmartHVAC app, Amazon Alexa, or Google Assistant for seamless voice or mobile app adjustments.

Wireless Remote Control: Adjust temperature, fan speed, and mode from anywhere in the room.

Follow Me® Technology: The system detects the remote’s location to maintain precise comfort levels where you need it most.

Custom Scheduling: Set cooling and heating schedules to match your lifestyle and energy-saving goals.

Reliable Year-Round Comfort

Cooling Capacity: 9,000 BTU (Ideal for rooms up to 400 sq. ft.)

Heating Capacity: 9,000 BTU, making it a true all-season system with high-efficiency performance in both hot and cold conditions.

Dry Mode: Functions as a dehumidifier, reducing excess moisture to improve indoor air quality and comfort.

Durability & Weather Resistance

Gold Fin® Corrosion Protection: The outdoor condenser is coated with anti-corrosion technology, extending its lifespan and making it suitable for coastal or high-humidity environments.

Auto Restart & Sleep Mode: Protects against power outages and optimizes comfort for energy-efficient nighttime operation.

Technical Specifications

Cooling Efficiency: 23.6 SEER2

Heating Efficiency: 10.3 HSPF2

Voltage: 115V (Standard residential electrical compatibility)

Line Set Length: 25-ft Pre-Charged QuickConnect® (Refrigerant: R-454B)

Indoor Unit Sound Level: As low as 24.5 dB for quiet operation

Airflow Control: Adjustable 4-way directional louvers

What’s Included?
✔ 9,000 BTU MRCOOL DIY® 5th Gen Indoor Air Handler (115V)✔ 9,000 BTU MRCOOL DIY® 5th Gen Outdoor Condenser (115V)✔ 25-ft Pre-Charged QuickConnect® Line Set (R-454B Refrigerant)✔ DIYPRO® Cable for easy electrical connections✔ Wireless Remote Control✔ MRCOOL SmartHVAC USB Controller® (Compatible with Google Assistant & Amazon Alexa)
Smart phone not included.
Industry-Leading Warranty for Peace of Mind

7-Year Compressor Coverage
5-Year Parts Protection
eligible for the MRCOOL® Care Program enrollment

Experience effortless comfort, energy savings, and smart home convenience with the MRCOOL DIY® 5th Generation 9,000 BTU Mini Split System—a powerful, easy-to-install, and cost-effective HVAC solution designed with homeowners in mind.
SPECIFICATIONS & DIMENSIONS
Dimensions & Weight

Condenser Dimensions
30.12 W" x 11.93 D" x 21.85 H"

Air Handler Dimensions
31.57 W" x 7.44 D" x 11.69 H"

Condenser Weight
65.48 lbs / 29.7 kg

Air Handler Weight
24.91 lbs / 11.3 kg

Capacity & Performance

Zone Capacity
1

Cooling Capacity
9,000 BTU

Outdoor Operating Temperature (Cooling)
-13°F - 122°F

EER2
14

SEER2
23.6

Heating Capacity
10,000 BTU

Outdoor Operating Temperature (Heating)
-13°F - 75°F

HSPF2-4
11.5

HSPF2-5
8.6

Coverage Area
200 - 350 sq ft.

Outdoor Noise Level
54 dB(A)

Indoor Noise Level (Hi/Mi/Lo)
43.0/39.5/33.5/24.0/18.0 dB(A)

Electrical Requirements

Voltage
115V

Phase
1

Cycle
60 Hz

Max Fuse Breaker
20A

Min Circuit Ampacity
18A

Refrigerant & Piping

Refrigerant Type
R-454B

Refrigerant Volume
30.34 oz

Liquid Line Size
1/4"

Suction Line Size
3/8"

Max Line Set Length
82 ft.

Features

Inverter
DC

Compressor Type
Rotary

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, Energy Star Certified, AHRI Certified

Warranty
7 Years Compressor5 Years Parts

 
 
What's the difference between the 5th Gen and 4th Gen?
The 5th Gen MRCOOL DIY® Mini Split offers several key upgrades over the 4th Gen, focusing on efficiency, advanced technology, and eco-friendliness.
Here’s what’s new with the 5th Gen:

Next-Gen R-454B Refrigerant: A more environmentally friendly refrigerant with lower global warming potential (GWP), compliant with the latest HVAC regulations.

Higher Energy Efficiency: Improved SEER2 ratings for greater energy savings and optimized performance.

Enhanced System Reliability: Upgraded components for better heating and cooling performance.

Can I install it myself, or do I need a professional?The MRCOOL DIY system is designed for homeowners and doesn’t require HVAC tools. You can install the indoor and outdoor units yourself using the pre-charged Quick Connect® lines. However, a licensed electrician is required for the electrical hookup to ensure safety and code compliance

Does it work in cold weather?

Yes. MRCOOL 5th Gen systems feature low-ambient heating and can provide reliable heat even when outdoor temperatures drop to around 5°F
How do I know what BTU size I need for my rooms?
A general rule of thumb is 20 BTU per square foot of space. Here's a rough guide:

6,000 BTU = 100 - 150 sq ft
9,000 BTU = 150 - 350 sq ft
12,000 BTU = 351- 500 sq ft
18,000 BTU = 501 – 750 sq ft
24,000 BTU = 751 – 1,000 sq ft
36,000 BTU = 1,001 - 1,500 sq ft

Some additional factors may impact performance such as insulation, ceiling height, sun exposure and the number of appliances in the room. For assistance, contact our Product Experts

Does it heat as well as cool?Yes. All 5th Gen models are heat pumps, providing both heating and cooling for year-round comfort.

Is it Wi-Fi compatible?
Yes. The MRCOOL SmartHVAC app allows smartphone control and works with Amazon Alexa and Google Assistant.
What is the warranty?
The MRCOOL 5th Generation DIY Mini-Split systems offer the following warranty coverage:

7-Year Compressor Replacement Warranty: This warranty ensures that if the compressor fails within the first seven years, MRCOOL will provide a replacement.

5-Year Parts Warranty: This warranty covers all parts of the system for five years from the date of purchase.

 
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