The 75 ft 1/4" x 3/8" mini split line set is a high-performance insulated copper tubing solution designed for ductless mini split air conditioners, heat pump systems, and HVAC refrigeration installations.

This copper line set connects the indoor evaporator and outdoor condenser units, ensuring efficient refrigerant flow and optimal system performance.

Manufactured with 99.9% pure copper, the tubing meets ASTM B280 and C12200 standards, providing excellent durability, corrosion resistance, and long-term reliability in HVAC applications.

The 75 ft extended length is ideal for installations where longer piping distances are required, such as multi-room or complex building layouts.

Technical Specifications of the 1/4" x 3/8" Mini Split Line Set

This HVAC copper line set is engineered to meet international quality and safety standards.

Key Specifications

• Pipe Size: 1/4 inch + 3/8 inch (6.35 mm + 9.52 mm)

• Length: 75 ft (22.8 m)

• Copper Material: 99.9% Pure Copper

• Copper Standard: ASTM B280 / C12200

• Insulation Material: Polypropylene or Rubber Insulation

• Temperature Range: -40℃ to 120℃

• Pressure Rating: 2100 – 7000 PSI

• Flame Resistance: UL94 / ASTM E84 compliant

These specifications ensure safe and efficient operation in modern HVAC systems.

Designed for 9000–12000 BTU Mini Split Air Conditioners

The 1/4" liquid line and 3/8" suction line configuration is commonly used for 0.75 ton to 1 ton mini split air conditioning systems, equivalent to 9,000–12,000 BTU capacity.

This makes the line set ideal for:

• Bedrooms and living spaces

• Small offices

• Apartments and residential installations

• Light commercial HVAC systems

Using the correct line size ensures proper refrigerant circulation and system efficiency.

High-Purity Copper Tubing for Reliable HVAC Performance

Copper is the industry standard for HVAC refrigerant piping systems due to its superior properties.

Key benefits include:

• Excellent thermal conductivity for efficient cooling

• Strong resistance to corrosion and oxidation

• High pressure tolerance for modern refrigerants

• Long service life with minimal maintenance

These advantages make copper tubing essential for reliable HVAC system operation.

99.9% Pure Copper

Black Rubber Insulated Pipe

Plastic Cap

Features of pipe insulation tubing:

● Pipe Insulation, Material Black Rubber, Temp Range -40 Degrees to 120 Degrees.

● The pipe insulation has a better function of moisture condensation. Insulation material is both the insulation layer and moisture-proof layer.

● There is no need to drop the water vapor permeation protective layer so that it has a better moisture condensation function.

Factory-Applied Insulation for Energy Efficiency

The line set features pre-insulated copper pipes, which improve energy efficiency and simplify installation.

Benefits of factory insulation:

• Maintains stable refrigerant temperature

• Reduces heat loss and energy consumption

• Prevents condensation buildup

• Eliminates the need for additional insulation work

This design helps HVAC technicians save time while improving system performance.

UV-Resistant Insulation for Indoor and Outdoor Use

The insulation is made of UV-resistant polypropylene or rubber material, allowing the copper line set to perform reliably in both indoor and outdoor environments.

Key features include:

• UV and weather resistance

• Moisture and corrosion protection

• Flame retardant performance

• Durable long-term structure

The insulation meets ASTM E84, UL94, ASTM D1056, and ASTM G21 standards, ensuring safety and durability.

High Pressure Resistance for Modern Refrigerants

This mini split line set is engineered to withstand high refrigerant pressures ranging from 2100 PSI to 7000 PSI, far exceeding the typical requirements for R410A systems (~700 PSI).

This ensures safe operation in high-efficiency HVAC systems and reduces the risk of pipe failure.

Flexible Copper Coil for Easy Installation

The 75 ft copper line set is supplied in a flexible coil, allowing easy installation in complex layouts.

Installation advantages include:

• Easy routing through walls and ceilings

• Reduced need for joints and connectors

• Faster installation process

• Lower risk of refrigerant leakage

This flexibility is especially valuable in long-distance HVAC installations.

Wide Applications for HVAC and Refrigeration Systems

The 1/4" x 3/8" insulated copper line set is suitable for a wide range of applications:

• Ductless mini split air conditioners

• Heat pump systems

• Central HVAC systems

• Refrigeration equipment

• Residential and light commercial installations

Its versatility makes it a reliable choice for HVAC professionals.

Multiple Insulation Options for Different Installation Needs

The mini split line set is available with various insulation thickness options to suit different environments:

• 8 mm / 9 mm / 10 mm / 13 mm / 19 mm / 25.4 mm

These options allow installers to select the appropriate insulation based on climate conditions and energy efficiency requirements.

Custom Mini Split Line Set Solutions Available

Professional HVAC manufacturers offer customization services to meet project-specific needs.

Customization options include:

• Custom pipe sizes

• Different insulation materials and thickness

• Custom lengths

• OEM logo printing

• Private label packaging

These solutions are ideal for HVAC distributors and contractors building their own brands.

Mini Split Line Set

1/4 + 3/8 Mini split line set used for 0.75TON - 1.0TON mini split air conditioner.

1/4 + 1/2 Insulated copper line set used for 1.5TON - 2.0TON mini split air conditioning.

1/4 + 5/8 Insulated copper piping used for 2.0TON - 2.5TON split air conditioner system.

3/8 + 5/8 Insulated copper tube apply for 3.0TON - 4.0TON ductless mini split air conditioner.

3/8 + 3/4 Insulated copper tubing used for 4.5TON - 6.0TON split air conditioner installation.

3/8 + 7/8 Insulated copper piping apply for 6.0TON - 8.0TON ductless mini split air conditioner.

Air conditioning copper line sets 1/4 + 3/8 used for 0.75P and 1P split air conditioning.

Copper pipe kit 1/4 + 1/2 commonly used for 1.5P and 2P mini split air conditioners.

1/4 + 5/8 Insulated copper line set used for 2P and 2.5air conditioner system.

3/8 + 5/8 Mini-split copper line set apply for 3P and 4P ductless mini split air conditioner.

3/8 + 3/4 Copper pipe kit used for 4.5P and 6P split aircon installation.

3/8 + 7/8 Insulated copper piping apply for 6P - 8p TON ductless mini split air conditioner.

1/4 + 3/8 Mini split line set used for 9000BTU and 12000 BTU split air conditioner.

All copper line set 1/4 + 1/2 commonly used for 12000 BTU and 18000 BTU mini split air conditioners.

1/4 + 5/8 Insulated copper line set used for 24000 BTU and 30000 BTU air conditioner system.

3/8 + 5/8 Mini-split line set apply for 36000 BTU and 48000 ductless air conditioner.

3/8 + 3/4 Mini split line set used for 54000 BTU and 72000 split air conditioner installation.

3/8 + 7/8 Insulated copper piping apply for 72000 BTU - 96000 BTU ductless mini split air conditioner.

Aircon copper line set 1/4 + 3/8 used for 9K and 12K split air conditioner.

High quality copper line set 1/4 + 1/2 commonly used for 12K and 18K mini split air conditioners.

1/4 + 5/8 Insulated copper line set used for 24K and 30K air conditioner system.

3/8 + 5/8 Mini-split line set apply for 36K and 48K ductless air conditioner.

3/8 + 3/4 Mini split line set used for 54K and 72K split air conditioner installation.

3/8 + 7/8 Insulated copper pipe apply for 72K - 96K ductless mini split air conditioner.

Why Choose DABUND Mini Split Line Set

DABUND is a trusted manufacturer specializing in HVAC copper line sets and insulated copper tubing since 2008.

Key advantages:

• Extensive manufacturing experience

• Large-scale production capacity

• Strict quality control systems

• Competitive factory pricing

• Global export capability

DABUND products are widely used in international HVAC markets and trusted by professionals worldwide.

DABUND FACTORY

We produce Insulated Copper Pipe, Mini Split Line Set and Aluminum Pipe and HVAC Parts

SGS Certificate

Mini Split Line Set is made of Polypropylene or Black Rubber with UV Resistant, meets ASTM E 84, UL94, ASTM D1056 and ASTM G 21

Exhibition

We join the exhibitions all over the word, just to facilitate customers to experience our mini split line set face to face.

FAQ

### What is a 75 ft mini split line set used for?

A 75 ft mini split line set is used to connect the indoor and outdoor units of a ductless mini split air conditioner or heat pump system when a longer installation distance is required. It allows refrigerant to flow efficiently between the evaporator and condenser, ensuring stable cooling and heating performance even in larger homes or complex building layouts.

### What size air conditioner uses a 1/4" x 3/8" line set?

A 1/4 inch liquid line and 3/8 inch suction line is typically used for 9,000 BTU to 12,000 BTU mini split air conditioning systems. These systems are commonly installed in residential rooms, offices, and small commercial spaces.

### Why should I choose a longer HVAC line set?

A longer HVAC line set provides more flexibility during installation. It allows the outdoor condenser unit to be placed farther from the indoor unit, which is useful for reducing noise, improving aesthetics, or overcoming space limitations in buildings.

### Why are copper pipes used in mini split line sets?

Copper pipes are widely used in HVAC refrigerant systems because they offer excellent thermal conductivity, durability, and corrosion resistance. Copper tubing can handle high-pressure refrigerants and ensures efficient heat transfer, making it the industry standard for air conditioning installations.

### Does the mini split line set come pre-insulated?

Yes. The 75 ft mini split line set comes with factory-applied insulation that helps maintain consistent refrigerant temperature, reduces energy loss, and prevents condensation on the pipe surface. This also simplifies installation by eliminating the need for additional insulation work.

### Can the 75 ft copper line set be cut to a shorter length?

Yes. The 75 ft insulated copper pipe can be cut to the required length during installation. HVAC technicians often adjust the pipe length based on the actual distance between the indoor and outdoor units, helping to reduce excess tubing and improve system efficiency.

### Is this copper line set compatible with modern refrigerants?

Yes. High-quality HVAC copper line sets manufactured according to ASTM B280 standards are compatible with modern refrigerants such as R410A and R32. These refrigerants require durable copper tubing capable of handling higher operating pressures.

### How long does a mini split copper line set last?

A properly installed mini split copper line set can last 20 years or more. Copper tubing is highly resistant to corrosion and environmental damage, while the insulation protects the pipe from UV exposure, moisture, and temperature fluctuations.

### Can this line set be used for both residential and commercial HVAC systems?

Yes. The 1/4" x 3/8" mini split line set is suitable for both residential and light commercial HVAC applications, including homes, apartments, offices, and small retail spaces. Its flexibility and durability make it a reliable solution for various cooling systems.

### Why choose a professional HVAC line set manufacturer?

Choosing a professional HVAC line set manufacturer ensures high product quality, consistent copper purity, and reliable insulation performance. Experienced manufacturers also provide OEM customization, strict quality control, and international certifications, making them trusted suppliers for HVAC contractors and distributors worldwide.