With so many brands and quality levels on the market, the question what to look for when buying a carbon film heater really matters. The wrong product means poor efficiency, a short service life and safety risks. In this complete buying guide we have gathered everything you need to check – product, accessories, supplier and installation – into a single list.
1. Define the Space and the Floor
- Floor type: Carbon film suits carpet, laminate and parquet; cable systems suit tiles and wet rooms. See this article for a comparison.
- Carpet type: Rubber-backed and very thick carpets are not suitable. Details: which carpets suit carbon film heaters.
- Purpose: Main heating or supplementary heating?
2. Check the Technical Specifications
| Specification | What to Check |
|---|---|
| Power (W/m²) | Does it suit the space and purpose? Typically 150–220 W/m² under carpet. |
| Width | Does it suit the room size and layout (50/80/100 cm)? |
| Busbars | Are the copper busbars thick and properly laminated? |
| Carbon strips | Are they uniform, continuous and evenly spaced? |
| Cutting lines | Are they clearly marked? |
| Technology | Standard or PTC (self-regulating)? |
| Label information | Are voltage, power, model and manufacturer printed on the film? |
3. Ask for Documents and Certificates
- CE marking and declaration of conformity
- Independent laboratory test reports
- User and installation manual in your language
- Written warranty certificate (with period and coverage clearly stated)
4. Plan All the Accessories
- Thermostat: Sufficient current rating and AF mode with floor sensor. See our thermostat guide.
- Clamps and insulating tape: High-quality connection materials compatible with the film.
- Underlay: Thermal insulation felt or reflective underlay, plus a moisture barrier.
- Protective devices: A suitable circuit breaker and a 30 mA RCD.
- Control panel: Required for zoning in large areas.
5. Calculate Power and Consumption in Advance
Before buying, calculate the total installed power and estimated monthly bill, and check that your existing circuit can carry the load. Use our electricity consumption guide for the method.
6. Evaluate the Supplier
- Do they carry out a site survey and power calculation?
- Do they offer installation and commissioning?
- Do they provide on-site service and spare parts during the warranty period?
- Do they have reference projects?
7. Read the Price Correctly
Ask whether the price per m² refers to net film area or room area, and whether the thermostat, panel and labour are included. We explain the factors affecting price in carbon film heater prices.
Buying Checklist
- Are the floor and carpet type suitable for carbon film?
- Are the film power and width right for the space?
- Is there a CE certificate, test report and written warranty?
- Are the thermostat current rating and sensor type suitable?
- Are underlay, clamps and insulating tape included?
- Have an RCD and circuit breaker been planned?
- Will installation be carried out by a qualified team?
Frequently Asked Questions
How can I tell a quality carbon film?
Uniform carbon strips, thick and neatly laminated busbars, clear label information on the film and full documentation are the key indicators of quality.
Can I buy a carbon film heater online and install it myself?
You can lay the film yourself, but the electrical connections, protective devices and tests must be carried out by a qualified electrician. See our installation guide for the steps.
Do I need PTC film?
It is not essential, but it adds extra safety in areas with a high risk of trapped heat (e.g. where items may be placed on the floor).
Conclusion
The right carbon film heater has the correct power and width for the space, is certified, made from quality materials and planned together with the right accessories. Read what is a carbon film heater? for the basics, or contact us for product selection and turnkey installation.
