PEX-AL-PEX piping 16 x 2 for heating, underfloor heating and water

Product detailed description

This PEX-AL-PEX pipe is commonly used in residential and commercial buildings for central heating systems, underfloor heating and domestic water distribution. The five-layer structure ensures mechanical strength, thermal stability and resistance to oxygen diffusion. Installers typically work with this pipe in radiant floor systems, where flexibility and long-term reliability are essential. The pipe can be bent manually for simple installations or with a bending spring for tighter curves, making it suitable for both small and large-scale projects.

The pipe is designed for use in closed heating circuits, where oxygen ingress can cause corrosion of metallic components. Its oxygen barrier prevents this, ensuring longer system lifespan. The smooth inner surface reduces flow resistance and minimises scale formation. The pipe is available in 200 m rolls and requires a minimum order of 10 m increments. It is compatible with a range of connection methods, allowing flexibility during installation.

Technical parameters

Available dimensions	16 x 2,0 mm
Color	White
Linear expansion coefficient	0,026 mm/m.K
Relative roughness coefficient	0,007 mm/m
Thermal conductivity	0,45 W/m.K
Maximum allowable operating temperature	Short-term 95 °C, 70 °C continuous operation
Maximum allowable operating pressure	10 bar
Standards	DIN EN ISO 21003
Water volume	0,113 l/m
Recommended connections	Threaded connections
Minimum bending radius without tools	Min. 5 x outer diameter (in mm)
Minimum bending radius with bending spring	2 x outer diameter (in mm)
Material class	B2 according to DIN 4102
Inner diameter	11,9 mm
Aluminium layer	0,20
Pipe composition	PEX/AL/PEX plastic-aluminium
Country of origin	EU
Weight	0.1 kg
Code	PEXALPEX 162
Brand	Wigell

The technical parameters are critical for selecting the correct pipe for specific applications. The maximum allowable operating pressure of 10 bar determines its suitability for low-pressure heating systems and water supply. The continuous operating temperature of 70 °C and short-term tolerance of 95 °C make it appropriate for conventional heating systems. The thermal conductivity of 0.45 W/m.K contributes to efficient heat transfer while maintaining structural integrity. The oxygen barrier thickness ensures effective isolation of the system from atmospheric oxygen.

Installation and connection

The PEX-AL-PEX pipe can be joined using brass threaded or compression fittings. Threaded connections require accurate cutting and deburring to ensure a tight seal. Compression fittings require proper alignment and tightening to avoid leaks. The recommended minimum bending radius without tools is five times the outer diameter, while a bending spring allows a tighter radius of twice the outer diameter. During installation, it is important to avoid sharp bends or kinks that could restrict flow or damage the pipe.

• Cut the pipe cleanly with a dedicated pipe cutter or hacksaw
• Deburr the cut ends to remove any rough edges
• Apply a small amount of lubricant to the fitting threads if required
• Use a torque wrench to tighten threaded connections to the manufacturer's specifications
• Check all joints for leaks after installation
• Support the pipe at regular intervals to prevent sagging

Common installation mistakes include using inappropriate cutting tools, which can lead to uneven cuts and poor sealing, and over-tightening fittings, which can damage the pipe or fitting threads. Ensuring that the pipe is properly supported and not subjected to excessive bending or compression is also essential for long-term performance.

Compatibility and accessories

This PEX-AL-PEX pipe is compatible with standard heating and water supply systems. It works well with radiant floor heating manifolds, thermostatic valves and circulation pumps. When installing, it is necessary to order additional fittings such as threaded or compression couplings, elbows, tees and valves. The recommended fittings for this pipe are threaded connections, which provide reliable sealing and ease of installation. For larger systems, it may also be combined with other PEX-AL-PEX pipes of different diameters, such as the PEX-AL-PEX 20 x 2, to accommodate varying flow requirements.

• Threaded couplings and elbows
• Compression fittings for quick connections
• Valves for flow control
• Manifold sets for underfloor heating systems
• Expansion loops for thermal compensation

Technical background for designers

The PEX-AL-PEX pipe is constructed from three layers: an inner and outer layer of cross-linked polyethylene (PEX), with a middle layer of aluminium bonded with adhesive. This composite structure provides high mechanical strength, thermal stability and resistance to oxygen diffusion. The PEX layers offer flexibility and resistance to chemical degradation, while the aluminium layer enhances thermal conductivity and structural rigidity. The oxygen barrier prevents the ingress of atmospheric oxygen into the system, reducing the risk of corrosion in metallic components such as radiators, boilers and heat exchangers.

When integrated into a heating system, the pipe must be sized according to the required flow rate and pressure drop. The hydraulic characteristics of the pipe, including its internal diameter and relative roughness, influence the system's efficiency. Proper insulation of the pipe is also important to reduce heat loss and improve overall system performance. The service life of the pipe is affected by factors such as operating temperature, pressure fluctuations and the quality of installation and maintenance.

Service and operation

During operation, it is important to periodically inspect the system for leaks, especially at connection points. Any signs of leakage should be addressed immediately to prevent water damage and system inefficiency. The pipe should also be checked for physical damage, kinks or excessive bending that could restrict flow. In systems with high mineral content in the water, periodic flushing may be necessary to remove scale deposits and maintain flow efficiency. However, the smooth inner surface of the PEX-AL-PEX pipe helps to reduce the rate of scale formation compared to other pipe materials.

There are no specified service intervals for this pipe, as it is designed for long-term use with minimal maintenance. However, if the system experiences frequent pressure surges or temperature fluctuations, additional monitoring may be advisable. The pipe's resistance to chemical and thermal degradation ensures stable performance over time, provided that it is installed correctly and operated within its specified limits.

Frequently asked questions

Can this pipe be used with copper fittings?
Yes, the PEX-AL-PEX pipe can be connected to copper fittings using brass threaded or compression fittings. Ensure that the fittings are compatible with PEX-AL-PEX pipe and that the connections are properly tightened.

What is the recommended method for cutting this pipe?
The pipe should be cut using a dedicated pipe cutter or a fine-toothed hacksaw. After cutting, the ends should be deburred to remove any burrs or rough edges that could interfere with the sealing of the fittings.

Is it possible to bend this pipe manually without a bending spring?
Yes, the pipe can be bent manually without a bending spring, provided that the minimum bending radius of five times the outer diameter is maintained. For tighter bends, a bending spring is recommended to prevent kinking.

Can this pipe be used in radiant floor heating systems?
Yes, the PEX-AL-PEX pipe is suitable for radiant floor heating systems due to its flexibility, thermal stability and resistance to oxygen diffusion. It can be installed in loops with appropriate manifold sets and valves for flow control.