MRCOOL 5th Gen DIY 25ft 3/8 x 5/8 Lineset for DIY 24K & 36K Indoor - R454B, DIY25-3858-O

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MRCOOL 5th Gen DIY 25ft 3/8 x 5/8 Lineset for DIY 24K & 36K Indoor - R454B, DIY25-3858-O

Name: MRCOOL 5th Gen DIY 25ft 3/8 x 5/8 Lineset for DIY 24K & 36K Indoor - R454B, DIY25-3858-O
Brand: MRCOOL
SKU: DIY25-3858-O
Price: 457.00 USD
Availability: InStock

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SKU: DIY25-3858-O

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25 ft pre-charged lineset for 5th Gen DIY 24K and 36K systems
3/8" liquid line, 5/8" suction line
Snap-together Quick Connect fittings — no brazing, flaring, or vacuum pump needed
Pre-charged with eco-friendly R-454B refrigerant
UV-resistant insulation for outdoor durability

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*Please Note: This timeline is an estimate. Certain products may require an additional 1 week for manufacturing. Please speak with your sales rep, Matthew, for official details and confirmation before placing your order.

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Pre-Charged R454B • 100% DIY Installation • 25-Foot Reach

MRCOOL 5th Gen DIY 25ft 3/8" x 5/8" Lineset for DIY 24K & 36K Indoor Units

Bridge the gap between your high-capacity indoor air handler and outdoor condenser with the MRCOOL 5th Gen 25ft Pre-Charged Lineset (DIY25-3858-O). Specifically engineered for 24,000 and 36,000 BTU 5th Generation DIY mini-split systems, this 25-foot lineset delivers a clean, professional-grade connection without the need for specialized HVAC tools. Factory-sealed and pre-charged with the latest low-GWP R454B refrigerant, it completely eliminates the costly and time-consuming process of vacuuming and charging lines. Thanks to MRCOOL's patented Quick Connect fittings, you can achieve a secure, leak-proof seal with just a simple twist of a wrench.

MRCOOL 5th Gen DIY 25ft 3/8" x 5/8" Lineset Applications

Standard residential installations connecting a ground-level condenser to a first-floor or basement air handler.
System expansions requiring an exact 25-foot span for high-capacity 24K or 36K BTU units.
Installations requiring a seamless, tool-free connection without the expense of hiring a licensed HVAC technician.
Eco-conscious upgrades requiring full compliance with the latest R454B refrigerant standards.

Engineered to provide the exact 3/8" liquid and 5/8" suction diameters required for optimal high-BTU refrigerant volume and efficient climate control.

MRCOOL 5th Gen DIY 25ft 3/8" x 5/8" Lineset Specifications

SKU	DIY25-3858-O
Length	25 Feet
Liquid Line Size	3/8 Inch
Suction Line Size	5/8 Inch
Compatibility	5th Gen DIY 24K & 36K BTU Indoor Handlers
Refrigerant Type	Pre-Charged with R454B
Connection Type	Quick Connect Patented Fittings

Why Choose the MRCOOL 5th Gen 25ft DIY Lineset

Zero Specialized Tools Required: The Quick Connect fittings create an airtight, leak-proof seal using standard hand tools.
Eco-Friendly & Future-Proof: Factory-charged with R454B, an environmentally conscious refrigerant that meets updated efficiency and environmental regulations.
Heavy-Duty Insulation: Robust outer insulation protects against condensation, energy loss, and harsh outdoor elements to ensure long-term reliability.
Massive Savings: Empowers you to completely bypass expensive professional vacuuming, flaring, and charging fees.

The MRCOOL 5th Gen 25ft DIY Lineset (DIY25-3858-O) provides the exact length and robust construction you need to securely connect your high-BTU system, ensuring maximum efficiency and a true do-it-yourself installation experience.

Key Information

Order Cutoff Time: 2:00 PM EST
Order Handling Time: 1–3 business days (Monday–Friday)
Transit Time: 1–7 business days (Monday–Friday)
Total Estimated Delivery Time: 3–11 business days (Monday–Friday)
Shipping Availability: Free Shipping On some Items In The Contiguous United States only

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Frequently Asked Questions

It is built for 5th Gen DIY 24K and 36K BTU indoor air handlers, with a 3/8" liquid line and 5/8" suction line sized for those higher-capacity systems.

The DIY25-3858-O is 25 feet long, a common length for connecting a ground-level condenser to a first-floor or basement air handler.

No. The lineset arrives factory-sealed and pre-charged, and MRCOOL's patented Quick Connect fittings seal with standard hand tools, so no vacuuming, flaring, or charging is needed.

It is pre-charged with R454B, a lower-GWP refrigerant that meets current environmental regulations.

No. Because the lineset is sealed and pre-charged with refrigerant, cutting it would release the charge, so pick the length that best matches your installation.

Yes. Heavy-duty outer insulation helps prevent condensation and energy loss and protects the lines from outdoor weather.

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MRCOOL 5th Gen DIY 25ft 3/8 x 5/8 Lineset for DIY 24K & 36K Indoor - R454B, DIY25-3858-O

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