Installation Best Practice

Best Practice Installation Guideline

Heatwell over many years of underfloor heating installation has developed a "best practice" set of guidelines.

The time period between installing the underfloor heating cable and the final flooring product is where the greatest likelihood of damage to the cable will occur. Undiagnosed damage to the underfloor heating cable will result in the expensive process of fault finding and repair. Something that is best avoided, as this can prove to be time and cost expensive.

Following our Best Practice Guidelines are essential for the Heatwell 25-year cable warrantee to apply. Please watch our Best Practice video.

Heatwells Pro Series cable have been independently tested in NZ. Each cable will have an ohm's value on the spool. Ohms are the resistance of each cable and will vary depending on the length. Ohms will also vary slightly with temperature. Our cables are usually tested at around 20 degrees Celsius. If the room temperature is hotter or colder there will be a slight variance (hotter will mean a lesser ohm reading). However, any ohms reading needs to be very similar to the ohms of the cables recorded from the test.

Taking ohms readings during the installation process is essential. A cable alarm will only sound if the underfloor heating cable is cut. A cable alarm is only a continuality alarm and will sound when the circuit has been broken. A cable alarm will not warn the installer if the cable has been crushed or damaged. A crushed cable will increase the resistance and create a hot spot at the crushed point. Only an increase in an ohm reading will show damage to a cable.

Crushing can occur if something heavy is dropped on the cable. This can happen during the cable installation process or during the installation of the final flooring product. Our system of putting fiberglass mesh over the cable and locking the cable in with a self-leveling compound helps protect the cable during installation of the final flooring product. However, you should never assume the cable has not been damaged during the final flooring product install.

Crushing can also occur if the cable is pinched (imagine a pinched garden hose) during the install process. Keeping the spool of the cable on the same side, while unravelling slowly, will help to reduce the chances of a pinch. If you pinch the cable accidently, an ohm reading should be done immediately. There is no use in continuing to install a damaged cable.

All installers will need a multi-meter capable of reading kOhm's.

Best Practice Installation Video

Best Practice Installation Steps

Take a photo of the test readings that come with the underfloor heating cable.
Test the cable with a multi-meter. Make sure the test is very similar to the recorded test. The reading may vary slightly due to room temperature. Take a photo of the test.
Fully install the underfloor heating cable including the cold tails to the flush box. If anything happens that may incur damage during install, test immediately.
When all the cables are in place with the cold tails drawn through the flush box, test the ohms against the test readings from Step 2. We are ensuring no damage has been done during the install process. Take another photo of the test.
Write the ohms test reading on a piece of tape and attach it to one of the cold tails. Take a photo. The installer is now fully covered!
The installer of the thermostat (electrician) will then check against the ohms reading. The electrician should take a photo of the test. The installer of the final flooring product can also check against an ohm reading if necessary.
There is still significant risk of cable damage from the final flooring installer or from an installer drilling a hole in the wrong spot. Please test the ohms reading immediately if there is any possibility of damage.