Premium 50 ft pre-insulated copper tubing with 1/4″ liquid line and 3/8″ suction line — designed for efficient, reliable refrigerant transfer in mini split air conditioners, ductless HVAC systems, and other split system installations where moderate line length is required.
The insulated copper tube is twin already. So buy it now.
Product Overview – Pre-Insulated HVAC Refrigerant Tubing
This pre-insulated copper tubing line set provides a continuous 50 ft run featuring factory-applied insulation that helps maintain stable refrigerant temperatures, reduces thermal loss, and minimizes condensation. It’s an ideal choice for HVAC installers and DIYers seeking a dependable line set for residential and light commercial applications.
Line Size Explained – 1/4″ & 3/8″ Configuration
1/4″ (≈6.35 mm) Liquid Line: Carries high-pressure refrigerant from the outdoor condenser to the indoor evaporator.
3/8″ (≈9.52 mm) Suction Line: Returns low-pressure refrigerant vapor back to the compressor.
This size pairing is widely used in modern mini split and ductless HVAC systems.
Factory-Applied Insulation for Performance
Maintains consistent refrigerant temperature throughout the run
Reduces heat gain and heat loss
Minimises surface condensation (“sweating”)
Eliminates the need for field-wrapped insulation
Key Features & Benefits
Efficient Refrigerant Transfer
The pre-insulated design helps preserve optimal refrigerant conditions along the entire line set, improving system efficiency and reducing unnecessary energy loss during cooling and heating cycles.
Durable Copper Construction
Made from 99.9% pure copper, this tubing provides excellent corrosion resistance, robust mechanical performance, and long-term durability — ensuring consistent HVAC operation over years of use.
Reduced Condensation & Moisture Issues
Factory insulation significantly reduces condensation on the tubing surface — a common cause of water damage and mildew — making it suitable for humid and variable climate conditions.
Features of pipe insulation tubing:
![White PE Embossed insulated pipe]( "insulated pipe")
HVAC Compatibility & Applications
Ideal for Mini Split & Ductless AC Systems
This pre-insulated copper tubing is suitable for:
Mini split air conditioners
Ductless heat pump systems
Residential and light commercial HVAC installs
The 50 ft length is ideal for typical indoor-to-outdoor unit distances without requiring extensions or couplings.
Compatible with Common HVAC Refrigerants
Engineered to work with widely used refrigerants including:
Technical Specifications
| Feature | Specification |
| Line Set Length | 50 ft (~15.24 m) |
| Liquid Line Diameter | 1/4″ (≈6.35 mm) |
| Suction Line Diameter | 3/8″ (≈9.52 mm) |
| Material | 99.9% Pure Copper |
| Insulation | Factory-applied thermal insulation |
| Applications | Mini split, ductless AC, heat pump systems |
| Compatible Refrigerants | R410A, R32, and similar HVAC refrigerants |
| Installation | Pre-insulated and ready to install |
Installation Tips for Optimal Performance
Plan the Line Path Before Installation
Prior to installation, measure the total distance between indoor and outdoor units. Choosing the most efficient routing reduces sharp bends that could restrict refrigerant flow and protect insulation performance.
Protect Insulation at Penetrations
Where the line set passes through walls or structural openings, use protective sleeves or grommets to prevent insulation damage and preserve thermal performance.
Secure Tubing with HVAC-Rated Supports
Use clips, straps, or professional HVAC brackets to secure the tubing along its run. Proper support reduces vibration, prevents sagging, and maintains insulation integrity.
![White PE copper line set]( "Copper Line Set")
Pre Insulated Copper Tubing
Size | Length | Insulation White PE | Flame Resistant |
1/4+3/8 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
1/4+1/2 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
1/4+5/8 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
3/8+5/8 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
3/8+3/4 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
1/2+3/4 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
3/8+7/8 | 15m/20m/25m/30m/50m | 8mm/9mm/10mm/13mm/19mm/25.4mm | M1/B1 |
1/4 + 3/8 Pre insulated copper tubing used for 0.75TON - 1.0TON mini split air conditioner.
1/4 + 1/2 Mini Split Line Set used for 1.5TON - 2.0TON mini split air conditioning.
1/4 + 5/8 Copper Line Set 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 Pipe 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 Pre insulated copper tubing used for 54000 BTU and 72000 split air conditioner installation.
3/8 + 7/8 Insulated copper pipe 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 Pre insulated copper tubing 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 50 ft 1/4" x 3/8" Pre Insulated Copper Tubing from DABUND PIPE
Reliable Performance for HVAC Professionals
Engineered with pre-insulated lines and high-quality copper, this tubing supports stable performance, energy efficiency, and low maintenance — ideal for busy HVAC contractors and installers.
Saves Time & Labor on Installation
Factory insulation eliminates the need for onsite insulation wrap, saving time, reducing labor costs, and improving installation consistency across jobs.
Trusted for Residential & Commercial Projects
Whether installing a new mini split system at home or servicing commercial HVAC systems, this line set delivers performance and peace of mind.
DABUND FACTORY
We produce Insulated Copper Pipe, Mini Split Line Set and Aluminum Pipe and HVAC Parts
![Factory Profile]( "Factory Profile")
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
![证书]( "证书")
Exhibition
We join the exhibitions all over the word, just to facilitate customers to experience our mini split line set face to face.
![TRADE SHOW PARTICIPATION]( "TRADE SHOW PARTICIPATION")
FAQ
1.Q:What is your payment terms?
A:TT,L/C AT SIGHT,CREDIT CARD etc
2.Q:What is your delivery terms?
A:EXW, FOB, CFR, CIF etc
3.Q:Are you trading company or manufacturer?
A:Manufacturer
4.Q:May I get a sample?
A:Yes, we can send you 3pieces free samples.
You just charge for the express cost is ok.
5.Q:Can I print my logo?
A:Yes of cause, we accept OEM and ODM.
6.Q:How long is your delivery time?
A:Usually 15-20days, if urgent, we can arrange to do in advance and delivery fast.
7.What does “1/4″ × 3/8″” mean?
It refers to the outer diameters of the refrigerant lines: 1/4″ liquid line and 3/8″ suction line — a common standard used in many mini split and ductless HVAC systems.
8.Is this tubing insulated?
Yes — this product includes factory-applied insulation designed to reduce thermal loss, minimize condensation, and eliminate the need for additional field insulation in most installations.
9.Can this line set be used outdoors?
Absolutely — the insulation jacket is weather-resistant and UV durable, making it suitable for outdoor refrigerant runs between indoor and outdoor HVAC units.
10.Is this tubing compatible with R410A systems?
Yes — this pre-insulated copper tubing is compatible with commonly used refrigerants such as R410A, R32, and other modern HVAC refrigerants when installed according to system and local code requirements.
