Electric heating cabel Hornisse 5,5mm (25m)

Product detailed description

Electric underfloor heating cables are commonly installed beneath screed layers in residential and commercial buildings to provide long-term thermal comfort. These systems integrate seamlessly with various floor coverings such as tiles, panels or carpets, and are particularly suited for well-insulated rooms. The Hornisse 5.5mm cable is embedded in the screed and operates at a controlled temperature, ensuring even heat distribution and minimal thermal fluctuations. Installers typically work with pre-calculated lengths to match room dimensions and heating requirements, ensuring optimal performance and energy efficiency.

When installing in bathrooms, kitchens or living areas, the cable is laid in a systematic pattern to avoid overlapping and ensure uniform coverage. The system functions as part of a broader heating strategy, often complementing or supplementing central heating systems. The cable’s low profile allows it to remain concealed within the screed, preserving interior aesthetics while maintaining structural integrity. Careful attention is required during installation to avoid mechanical damage and to ensure correct electrical connections.

Technical parameters

Code	HO HCABLE/15-375

Key parameters include a power output of 15 W/m, a maximum wire temperature of 45°C, and a minimum installation temperature of 5°C. These values are critical for determining the required length of cable per room and for selecting appropriate control components. The 230V supply voltage is standard for residential and light commercial applications, and the cable’s resistance and current draw must align with circuit design specifications to prevent overloading. The insulation materials (LSZH and XLPE/PVC) contribute to fire safety and durability in high-moisture environments.

Installation and connection

The installation process begins with preparing the subfloor and ensuring a clean, level surface. The cable is unrolled and positioned in a serpentine layout, maintaining a minimum bend radius of 50 mm to prevent stress on the insulation. A 2-core power cable with an earth braid is connected to the supply point, with a total length of 2.5 m provided for the supply lead. Connections should be made using approved junction boxes, and all joints must be sealed to prevent moisture ingress. A digital thermometer or thermostat is recommended for precise temperature regulation.

Common mistakes include incorrect spacing between cables, which can lead to uneven heating, or failure to account for thermal mass when setting the thermostat. It is also important to verify that the ambient temperature during installation is above 5°C to prevent material brittleness. After installation, a continuity test should be performed to confirm that the cable is undamaged and that all connections are secure. This ensures the system operates safely and efficiently once powered.

Compatibility and accessories

The Hornisse 5.5mm cable is compatible with standard 230V electrical systems and can be integrated with programmable thermostats or room controllers for automated operation. Additional accessories such as junction boxes, temperature sensors and control units are required for complete system functionality. Related products include the 15m, 40m, 60m, 80m, 100m, 120m variants of the same model, allowing flexibility in system design based on room size and heating demand. For larger installations, multiple cables can be connected in parallel to achieve the desired total output.

Technical background for designers

The Hornisse 5.5mm cable operates by converting electrical energy into heat through resistive conduction in the conductive core. The LSZH insulation minimises smoke and toxic gas emissions in case of fire, while the XLPE/PVC outer sheath provides mechanical protection and resistance to moisture. The cable’s dual-core construction ensures balanced current flow and reduces electromagnetic interference. When embedded in screed, the thermal mass of the material acts as a buffer, storing heat and releasing it gradually after the system is turned off. This enhances energy efficiency and reduces cycling frequency in the control unit.

Designers should consider the specific thermal conductivity of the screed material and the room’s insulation levels when planning the cable layout. Overlapping or insufficient spacing can cause localized overheating and reduce the system’s lifespan. The cable’s maximum operating temperature of 45°C ensures compatibility with standard flooring materials and prevents surface damage. Proper integration with a room thermostat or zone controller allows for precise temperature management and optimises energy consumption in both new builds and retrofit projects.

Service and operation

Once installed, the system requires minimal maintenance due to the absence of moving parts. Regular checks should include verifying the thermostat settings and ensuring that the control unit is functioning correctly. The cable itself is durable and resistant to mechanical stress when properly embedded in the screed. Any visible damage to the outer insulation should be repaired immediately to prevent short circuits or electrical hazards. In the event of system failure, the first step is to inspect the power supply and connections, followed by testing the cable’s continuity with a multimeter.

There are no scheduled service intervals specified in the technical documentation, as the cable is designed for long-term use with minimal degradation. However, if the system exhibits irregular performance such as inconsistent heating or high energy consumption, a diagnostic test should be conducted. This includes measuring the cable’s resistance and comparing it to the expected value for the installed length. If the resistance is significantly altered, the cable may need to be replaced. Routine visual inspections are recommended to detect any signs of wear or damage caused by external factors such as moisture or chemical exposure.

Frequently asked questions

Can the Hornisse 5.5mm cable be used in wet areas such as bathrooms?
Yes, the cable is suitable for installation in bathrooms and other high-moisture environments due to its waterproof insulation and resistance to condensation. It must be embedded in a non-conductive screed and connected to a GFCI-protected circuit.

Is it possible to cut the cable to a custom length?
No, the Hornisse 5.5mm cable is manufactured in fixed lengths and cannot be cut or modified. Each variant is designed for specific room sizes and must be selected according to the required power output and floor area.

How is the cable connected to the power supply?
The cable is supplied with a 2.5 m long power lead consisting of two conductors and an earth braid. This lead connects directly to the mains supply via a junction box, and all connections must be made by a qualified electrician in accordance with local electrical regulations.

Can multiple Hornisse 5.5mm cables be connected in parallel?
Yes, multiple cables can be connected in parallel to increase the total output of the system. The combined current draw must not exceed the capacity of the circuit breaker, and all cables must be of the same model and length to ensure even heat distribution.

Documents for download

• Hornisse Products (PDF)
• Manual EN (PDF)