MRCOOL DIY 5th Gen 66 Ft. 1/4" x 1/2" Line Set for DIY 18K Indoor (DIY66-1412-O)

MRCOOL DIY 5th Gen 66 Ft. 1/4" x 1/2" Line Set for DIY 18K Indoor (DIY66-1412-O)

SKU: DIY66-1412-O

Sale price$1,265.00 Regular price$1,527.00
Save 17%



In Stock Estimated delivery: Sep 13th-22nd
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Package Overview

This line set is compatible with MRCOOL's 5th Gen DIY Condenser to the MR COOL 5th Gen Air Handlers with 18K BTU.66 ft. line set is created by connecting a 50 ft. and 16 ft. line set with a coupler.Some assembly is requiredFor Multi-Zone systems, one line set per indoor unit is required to ensure the system will function properly.

Package Includes:

Description
Product Specs
Manuals & Guides

The MRCOOL 5th Gen DIY Line Set is a required component for installing your MRCOOL DIY ductless mini-split system. This 50-foot model is pre-charged with environmentally friendly R-454B refrigerant and works with MRCOOL's DIY 5th Gen 18K air handler units, featuring 1/4” liquid and 1/2” suction lines.

Equipped with Quick Connect fittings, the line set allows for fast, tool-free installation—no vacuuming, charging, or special certifications needed. Built with durable, kink-resistant materials and a leak-proof design, it ensures long-lasting, efficient performance. Available in multiple lengths, it’s the key to making your HVAC setup truly DIY-friendly.

Series

5th Gen DIY Line Set - R-454B

Compatible Air Handlers 18K 5th Gen DIY

Line Set Length

50 ft

Lineset Fitting Type Quick-Connection

Gross Dimensions

37.2" D x 4.92" H x 37.2" W

Color

White

Color Family

Bronze/Copper Metallic

Refrigerant Type

R-454B

Refrigerant Volume (Oz)

6.07

Liquid Line Size

1/4

Suction Line Size

1/2

Registered Warranty

N/A

Has Batteries

No

Contains Electronics No

Contains Chemicals

Yes

Contains Aerosol

Yes

Contains Compressed Gas

Yes

Proposition 65 Warning

Yes

Restricted States

GU;PR;VI

Net Weight (Lbs)

26.7

Gross Weight (Lbs)

32.2

Description
Product Specs
Manuals & Guides

The MRCOOL 5th Gen DIY Line Set is a required component for installing your MRCOOL DIY ductless mini-split system. This 16-foot model is pre-charged with environmentally friendly R-454B refrigerant and works with MRCOOL's DIY 5th Gen 18K air handler units, featuring 1/4” liquid and 1/2” suction lines.

Equipped with Quick Connect fittings, the line set allows for fast, tool-free installation—no vacuuming, charging, or special certifications needed. Built with durable, kink-resistant materials and a leak-proof design, it ensures long-lasting, efficient performance. Available in multiple lengths, it’s the key to making your HVAC setup truly DIY-friendly.

Series

5th Gen DIY Line Set - R-454B

Compatible Air Handlers

18K 5th Gen DIY

Line Set Length

16 ft

Lineset Fitting Type

Quick-Connection

Gross Dimensions

28.94" D x 4.92" H x 28.94" W

Color

White

Color Family

Bronze/Copper Metallic

Refrigerant Type

R-454B

Refrigerant Volume (Oz)

2.12

Liquid Line Size

1/4

Suction Line Size

1/2

Registered Warranty

N/A

Has Batteries

No

Contains Electronics

No

Contains Chemicals

Yes

Contains Aerosol

Yes

Contains Compressed Gas

Yes

Proposition 65 Warning

Yes

Restricted States

GU;PR;VI

Net Weight (Lbs)

8.8

Gross Weight (Lbs)

12.3

 

Description
Product Specs
Manuals & Guides

When one standard size DIY® QUICK CONNECT® LINE SET is not long enough, two standard QUICK CONNECT® LINE SETS can be combined using our DIY® COUPLER to increase the desired length of the QUICK CONNECT® LINE SETS.

Use this DIYCOUPLER if you have a 9K, 12K or 18K Air Handler. This also comes with 75ft of Communication Wire.

    Dimensions 11"W x 22.5"D x 4.5"H
    Unit Type Accessories
    Equipment Type Coupler
    Color Copper
    California Residents See Prop 65 WARNING
    Weight 6.39 lbs
    Freight Class 92.5

    Shipping & Returns

    Email Quote

    Customer Reviews

    Based on 40 reviews
    85%
    (34)
    13%
    (5)
    3%
    (1)
    0%
    (0)
    0%
    (0)
    R
    Robert W. (Marietta, GA)
    Decent Company

    I ordered a HVAC system and it arrived in a timely manner and with no apparent issues. I thought the system was defective once installed but it was the installers fault who wired it wrong. My only issue would be the fee (30% I believe) to return a defective item within the 30 day return policy. If it is defective the customer shouldn't have to pay a fee to return an item that is not operating as designed. Other than that this is a good company.

    P
    Peter K. (Phoenix, AZ)
    Pretty Easy Install and Works Great!

    Installed my own central HP system. It was a bit of work but nothing beyond a person with basic mechanical and electrical skills. It took me a while because I had to remove the existing electric forced air furnace from a pretty tight place. Some custom sheet metal work and a bit of custom electrical too. Worked perfectly when powered up and I actually like the thermostat provided, although I wish it was clearer how to set up a temperature set-back schedule. Pre-charged refrigerant piping was something new and I liked that too. The best thing is that my electric utility forked out $4,000 and that paid for the unit!

    W
    Wes D. (Chicago, IL)
    Installed and working great

    Installed with ceiling cassettes... Quiet and keeping us cool so far !

    C
    Chris S. (Denver, CO)
    Good product great customer service

    Very good customer service will be buying from them again

    M
    Marinus R.
    Install

    Was easy to install. Directions were easy to follow and unit is working great

    Why buy a MRCOOL from Home Outlet Direct?

    - We are an authorized MRCOOL dealer

    - Industry leading sales and customer service

    - Thousands of happy customers

    Real Customers. Real Results.

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