Pre-insulated double pipe AustroPEX HT double A125-2x32, PN6, for central heating installations, thermal insulation with PE foam, corrugated outer sheath HDPE PIP-XPD-125D32

Flexible pre-insulated pipe system for central heating with low heat losses

The double pre-insulated AustroPEX HT double A125-2x32 pipe is a factory-made, ready-to-install system composed of three layers: an inner carrier pipe, thermal insulation, and an outer corrugated sheath. Designed for operation in central heating systems at temperatures up to +95°C and a maximum working pressure of 6.6 bar at this temperature — ensuring safe performance even in demanding circuits with high supply temperatures.

The inner carrier pipe is made of cross-linked PE-Xa (SDR 11) with an EVOH oxygen diffusion barrier — providing complete protection against oxygen ingress, thereby extending the lifespan of the heating system and protecting boilers and pumps from corrosion. The color of the barrier (red, white, or gray) may vary by batch — this has no impact on technical parameters.

The thermal insulation consists of closed-cell, cross-linked XPE foam — absorbing no more than 1% water (per DIN 53428), ensuring stable thermal performance even under humid conditions. Its thermal conductivity is low: the U-value is 0.339 W/m·K, meaning minimal heat loss per meter of length — resulting in lower operating costs and reduced pump load.

The outer HDPE sheath features a corrugated structure — not only enhancing mechanical resistance to damage during transport and installation, but also enabling flexible bending without compromising insulation integrity. The minimum bending radius is 0.6 m, facilitating installation even in confined spaces.

The pipe is supplied in long coiled lengths — up to 260 meters per coil — reducing the number of joints and accelerating installation. Weight is approximately 1.8 kg/m, making it easy to transport and handle by a single person. No additional insulation or corrosion protection is required — fully resistant to chemical and electrochemical attack.

Why it works in practice?

• No need for additional insulation — fully ready from the manufacturer; no need for external “shells” or “wraps” after installation.
• Reduced pump load — the smooth inner PE-Xa surface generates lower flow resistance than steel; pumps operate less intensively.
• Fast installation — flexibility allows routing around curves and corners without requiring numerous connecting fittings.
• Long service life — no corrosion, resistance to microbiological attack, and stable insulation ensure the system requires no maintenance for decades.
• Installer safety — no heavy steel components; no risk of pipe damage during transport thanks to the rigid HDPE outer layer.

Applications

This system is suitable for both new central heating installations and modernization of existing networks. Ideal for residential, commercial, and public buildings. Can also be used as a supply line for heat pumps or cooling systems. Not suitable for transporting chemicals or systems operating above 6.6 bar at +95°C.

Installation requires the use of appropriate threaded or press-fit fittings, along with fixed supports — to compensate for thermal expansion of PE-Xa (approx. 10 mm/m at 70°C). Rubber end caps are recommended to protect pipe ends from mechanical damage.