The 50 ft 1/4″ × 3/8″ pre-insulated copper pipe is a professional HVAC refrigerant line set engineered for reliable cooling and heating performance in mini split air conditioners, ductless HVAC systems, heat pumps, and other split system installations requiring moderate line distances.
The Pre-insulated Copper Pipe is twin already. So buy it now.
Product Overview – Pre-Insulated HVAC Copper Piping
This pre-insulated copper pipe set features a 1/4″ liquid line and a 3/8″ suction line, each with factory-applied insulation to maintain consistent refrigerant temperatures, reduce thermal loss, and prevent condensation. The 50 ft length offers flexibility for typical indoor-to-outdoor unit spacing without needing field insulation wrapping.
Standard Refrigerant Pipe Sizes Explained
1/4″ (≈6.35 mm) Liquid Line – Carries high-pressure liquid refrigerant from the outdoor unit to the indoor coil.
3/8″ (≈9.52 mm) Suction Line – Returns low-pressure refrigerant vapor back to the compressor.
A widely adopted configuration for mini split and split system HVAC setups.
Factory-Applied Insulation for Efficiency
Factory insulation improves thermal retention along the line set.
Reduces heat gain and loss over typical HVAC line runs.
Minimises condensation (“sweating”) on the pipe surface.
Saves time compared to field-wrapped insulation.
Key Features & Benefits
Reliable Refrigerant Flow for HVAC Performance
Pre-insulated copper piping supports consistent refrigerant flow from outdoor to indoor units, helping reduce system stress, improve cooling/heating cycles, and support overall system efficiency.
Durable Copper Construction
Made from 99.9% pure copper, this line set delivers excellent corrosion resistance, high thermal conductivity, and robust mechanical strength — ensuring long-term reliability in both residential and light commercial HVAC applications.
Reduces Condensation & Moisture Issues
The insulated design significantly reduces condensation that can damage structural surfaces, ceilings, or walls — a common concern in humid environments.
Features of pipe insulation tubing:
![White PE Embossed insulated pipe]( "insulated pipe")
HVAC Compatibility & Applications
Ideal for Mini Split & Ductless HVAC Systems
This pre-insulated copper pipe set is perfect for:
Mini split air conditioners
Ductless HVAC systems
Heat pump cooling and heating systems
Residential HVAC installations
Light commercial HVAC applications
The 50 ft length accommodates moderate distances between indoor and outdoor units.
Works With Standard HVAC Refrigerants
Designed to be compatible with widely used HVAC 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 connect |
Installation Tips for Best Performance
Measure Route Before Starting
Measure the total path between indoor and outdoor units before installation to ensure the 50 ft line provides a smooth route without sharp bends that could restrict refrigerant flow.
Protect Insulation at Penetrations
Use wall sleeves or protective grommets at wall or structural penetrations to prevent insulation wear and maintain thermal performance.
Secure Line Set With HVAC-Rated Brackets
Use straps, clips, or HVAC-rated supports along the run to prevent sagging, reduce vibration, and preserve insulation integrity over time.
![White PE copper line set]( "Copper Line Set")
Pre-Insulated Copper pipe
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 pipe 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 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 pipe 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 pipe 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 Pipe from DABUND PIPE
Reliable HVAC Performance You Can Count On
With factory insulation and high-quality copper construction, this line set delivers dependable refrigerant flow, energy efficiency, and long-term durability — perfect for HVAC professionals and installers.
Saves Installation Time & Labor
Factory-installed insulation eliminates the need for onsite insulation wrapping, saving both time and cost while ensuring consistent thermal protection.
Ideal for Residential & Light Commercial Projects
Whether you’re installing a new mini split system at home or upgrading HVAC infrastructure in a commercial space, this 50 ft pre-insulated copper pipe provides versatility, 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]( "TRADE SHOW")
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 two refrigerant pipes: 1/4″ liquid line (refrigerant feed) and 3/8″ suction line (refrigerant return) — a common size pairing in many mini split and split system HVAC configurations.
8. Is this copper pipe insulated?
Yes — the line set comes with factory-applied insulation that improves thermal performance, reduces condensation, and eliminates the need for additional field insulation in most installations.
9.Can this line set be used outdoors?
Yes — the insulation jacket is weather-resistant and UV-durable, making it suitable for outdoor runs between indoor and outdoor HVAC units.
10.Is this compatible with R410A systems?
Yes — this pre-insulated copper pipe set supports common refrigerants including R410A and R32 when installed according to system specifications and local building codes.
