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MRCOOL® Pre-Charged Line Set for 2nd Gen Systems (R-454B | DIY Installation)

By Pre-Charged Line Set SKU NV15-3834-O
Regular price $337.00
Sale price $337.00 Regular price $421.25
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Line Set Length
Key Features At A Glance
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Estimated arrival: Jun 10 – Jun 12
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MRCOOL® No-Vac® Pre-Charged Line Set – 3/8" x 3/4" for Universal® 2nd Gen, Hyper Heat 2nd Gen, VersaPro® 2nd Gen & Cased A-Coil Systems

Complete your MRCOOL® central ducted HVAC installation with the MRCOOL® No-Vac® Pre-Charged Line Set, engineered specifically for R-454B refrigerant systems. Designed for compatibility with MRCOOL® Universal® 2nd Gen, Hyper Heat 2nd Gen, VersaPro® 2nd Gen, and Pre-Charged Cased A-Coil systems, this factory pre-charged line set delivers a faster, cleaner, and easier installation process without the need for vacuum pumps or refrigerant charging.

Featuring MRCOOL’s industry-leading No-Vac® Quick Connect technology, these pre-charged line sets are ideal for both professional HVAC installers and advanced DIY homeowners looking for a reliable and efficient HVAC installation solution.

Available Line Set Lengths

  • 15-Foot No-Vac® Pre-Charged Line Set
  • 25-Foot No-Vac® Pre-Charged Line Set
  • 35-Foot No-Vac® Pre-Charged Line Set
  • 50-Foot No-Vac® Pre-Charged Line Set

Need additional length? MRCOOL® DIY Couplers allow you to safely connect multiple line sets together for custom installation configurations. Because apparently houses refuse to place condensers exactly 15 feet away from air handlers like civilized structures.

Key Features & Benefits

  • Compatible with MRCOOL® 2nd Gen Systems – Designed for use with MRCOOL® Universal® 2nd Gen Heat Pumps, Hyper Heat 2nd Gen systems, VersaPro® 2nd Gen systems, and Pre-Charged Cased A-Coils.
  • Pre-Charged with R-454B Refrigerant – Factory sealed and ready for installation with no additional refrigerant charging required.
  • No-Vac® Quick Connect Technology – Eliminates the need for vacuuming, gauges, or specialty HVAC charging tools during installation.
  • Multiple Length Options Available – Choose from 15', 25', 35', or 50' line sets to fit your installation needs.
  • DIY Extendable Design – Compatible with MRCOOL® DIY Couplers for extended custom-length installations.
  • 3/8" Liquid Line & 3/4" Suction Line – Properly sized for optimized refrigerant flow and maximum system efficiency.
  • Durable Copper Construction – Manufactured with corrosion-resistant copper tubing and premium insulation for long-term reliability.
  • Eco-Friendly Refrigerant Compatibility – Supports R-454B refrigerant, a lower global warming potential (GWP) refrigerant designed to meet modern EPA efficiency standards.

Important Compatibility Notice

For R-454B Systems Only – This line set is specifically engineered for MRCOOL® R-454B refrigerant-based systems including Universal® 2nd Gen, Hyper Heat 2nd Gen, VersaPro® 2nd Gen, and compatible Cased A-Coils.

Not Compatible with R-410A Systems – Do not use with older MRCOOL® systems or any HVAC equipment requiring R-410A refrigerant. Improper refrigerant compatibility may cause system damage and void manufacturer warranty coverage.

Why Choose MRCOOL® No-Vac® Line Sets?

  • 100% genuine MRCOOL® factory-tested product
  • Pre-charged and sealed for simplified installation
  • No vacuuming or refrigerant handling required
  • Ideal for DIY-friendly installations and professional HVAC applications
  • Engineered for reliable performance and leak-resistant operation
  • Designed to work seamlessly with MRCOOL® R-454B systems

Buy from an Authorized MRCOOL® Dealer

When you purchase from MRCOOL HVAC Direct, you are buying from an authorized MRCOOL® dealer committed to providing genuine equipment, knowledgeable support, and dependable service.

  • 100% Genuine MRCOOL® Products – No aftermarket replicas or unauthorized resellers
  • Expert HVAC Support – Assistance with compatibility, installation, and system pairing
  • Fast & Reliable Shipping – Quick order processing and nationwide delivery
  • Competitive Pricing – Exceptional value on genuine MRCOOL® HVAC accessories and equipment

Upgrade Your MRCOOL® System Today

Choose the MRCOOL® No-Vac® Pre-Charged Line Set for a faster, cleaner, and more reliable installation experience. Designed specifically for MRCOOL® Universal® 2nd Gen, Hyper Heat 2nd Gen, VersaPro® 2nd Gen, and compatible Cased A-Coil systems using R-454B refrigerant, this line set helps ensure maximum performance, efficiency, and installation convenience.

No specs provided for this product yet.

NV Line Set Includes

Pre-Charged Line Set

Pre-Charged Line Set

DIY Line Set Adapters (Set of 4)

DIY Line Set Adapters (Set of 4)

Download installation manuals, spec sheets, and warranty documents for this system.

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Rated 4.7 / 5 Stars
4700+ Verified Reviews

Comfort That Speaks for Itself

See why homeowners and pros alike trust MRCOOL DIY systems to deliver comfort, savings, and easy installation.

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

I never thought I’d install my own HVAC system, but MRCOOL made it possible. The instructions were easy, and the pre-charged lines saved me from hiring a tech. Cools my garage workshop perfectly!

Jason R., North Carolina

Our MRCOOL mini-split runs really quiet — you can barely tell it’s on. Our electric bill dropped about 35% this summer. Very impressed with the efficiency

Megan L., Arizona

Installed this in my detached office. Took me a Saturday morning and a friend to lift the outdoor unit. Works flawlessly — heats in winter and cools in summer.

Daniel P., Texas

I swapped my old central unit for two MRCOOL DIY mini-splits. Same comfort, way lower bills. The inverter technology really makes a difference.

Jennifer C., Florida

Had a small question during installation and Vanessa picked up right away. They walked me through it step by step — best customer service I’ve had in years.

Chris B., Ohio

Keeps our sunroom comfortable in 100°F summers and comfy in the winter. The heat pump feature is amazing — one system for both heating and cooling!

Angela K., Kentucky

I’ve remodeled a few homes, and MRCOOL DIY systems are a game-changer. No need for HVAC pros or special tools — everything is plug-and-play.

Brandon S., Tennessee

DIY-Friendly Installation

Designed specifically for homeowners, the MRCOOL DIY system includes an installation template for the wall-mounted air handler, making it easy to place holes for refrigerant lines, cables, and drain connections accurately. The simplified design eliminates guesswork and helps you complete installation faster with confidence.

Heat Pump Technology – Heating & Cooling

The MRCOOL DIY system is a true heat pump, providing both heating and cooling in one system. It transfers heat rather than generating it, delivering highly efficient comfort year-round. The system can heat in temperatures as low as -13°F and cool in temperatures up to 122°F, keeping your home comfortable in nearly any climate.

Variable-Speed DC Inverter Compressor

The MRCOOL DIY system uses advanced DC inverter technology to continuously adjust compressor speed based on your comfort needs. Instead of constantly turning on and off like traditional systems, it runs at the optimal level to maintain temperature while using less energy. This results in lower energy costs, quieter operation, and longer system life.

DIY-Friendly Installation

Designed specifically for homeowners, the MRCOOL DIY system includes an installation template for the wall-mounted air handler, making it easy to place holes for refrigerant lines, cables, and drain connections accurately. The simplified design eliminates guesswork and helps you complete installation faster with confidence.

Heat Pump Technology – Heating & Cooling

The MRCOOL DIY system is a true heat pump, providing both heating and cooling in one system. It transfers heat rather than generating it, delivering highly efficient comfort year-round. The system can heat in temperatures as low as -13°F and cool in temperatures up to 122°F, keeping your home comfortable in nearly any climate.

Variable-Speed DC Inverter Compressor

The MRCOOL DIY system uses advanced DC inverter technology to continuously adjust compressor speed based on your comfort needs. Instead of constantly turning on and off like traditional systems, it runs at the optimal level to maintain temperature while using less energy. This results in lower energy costs, quieter operation, and longer system life.

Smart Control with Wi-Fi & Voice Assistants

Take full control of your comfort from anywhere using the MRCOOL SmartHVAC app on iOS or Android. Adjust temperature, monitor usage, and set automated comfort schedules. The system also integrates with Amazon Alexa and Google Assistant for convenient voice control.

No-Vac Quick Connect® Line Sets

Installation is simple thanks to MRCOOL’s patented Quick Connect® fittings. The pre-charged line sets come sealed with refrigerant and connect using basic hand tools — no vacuum pump or specialized HVAC equipment required. Just align the fittings, tighten with a wrench, and your system is ready to go.

Protected DIYPro™ Communication Cable

The MRCOOL DIYPro™ communication cable connects the indoor air handler and outdoor condenser while protecting electrical wiring inside a durable protective conduit. This heavy-duty cable helps shield wiring from weather exposure and accidental damage during installation.

Labeled diagram of MRCOOL DIY single zone ductless mini split heat pump system showing indoor air handler, outdoor condenser, SmartHVAC app control, remote, pre-charged line set, and Quick Connect fittings for DIY installation.

Smart Control with Wi-Fi & Voice Assistants

Take full control of your comfort from anywhere using the MRCOOL SmartHVAC app on iOS or Android. Adjust temperature, monitor usage, and set automated comfort schedules. The system also integrates with Amazon Alexa and Google Assistant for convenient voice control.

No-Vac Quick Connect® Line Sets

Installation is simple thanks to MRCOOL’s patented Quick Connect® fittings. The pre-charged line sets come sealed with refrigerant and connect using basic hand tools — no vacuum pump or specialized HVAC equipment required. Just align the fittings, tighten with a wrench, and your system is ready to go.

Protected DIYPro™ Communication Cable

The MRCOOL DIYPro™ communication cable connects the indoor air handler and outdoor condenser while protecting electrical wiring inside a durable protective conduit. This heavy-duty cable helps shield wiring from weather exposure and accidental damage during installation.