Installing Electric Cable
Not all electric radiant floor heating systems use mats or rolls to produce the heat. Before mats or rolls became popular, floor systems consisted of coiled electric heating cables. The procedure for installing electric heating cables may be outlined as follows:
1. Make sure the power supply is shut off before beginning any work.
2. Begin the electrical rough-in work by installing the electrical box for the thermostat on the wall.
3. Pull the power supply cable into the thermostat electrical box.
4. Punch out the conduit holes on the box. The heating cable and thermostat sensor leads will be pulled through these elec- trical box holes later.
5. Lay the cable out on the floor according to the specified coil pattern.
6. Staple the electric cable to the floor through plastic strapping to prevent the coils from moving out of position.
7. Pull the cable and thermostat sensor leads through the punched out conduit holes in the electrical box.
8. Cover the cable with a thin coat of mortar.
9. Allow the mortar a day to dry and then apply the floor cover- ing (for example, carpet, wood flooring).
10. Install the thermostat in the thermostat electrical box.
11. Connect to the power supply.
Note
Only a qualified HVAC technician or someone with an equivalent amount of work experience should be allowed to install an electrical radiant floor heating system. Electricity in inexperienced hands can cause serious injury and even death.
Servicing and Maintaining an Electric Radiant Floor Heating System There are no valves, fittings, or moving parts to service or repair in an electric radiant floor heating system. Consequently, there is no need for a maintenance schedule.
Note
Manufacturers provide repair kits with accompanying instructions for repairing mats or rolls damaged at the job site. They do not, however, warranty the repair or ensure proper function of the product following the repair because they have no means of con- trolling the repair work. Only a qualified electrician should make repairs to mats or rolls.
Caution
Before troubleshooting or repairing an electric heating system, make sure the power is turned off and the mat or roll is disconnected from the power source. Do not cut the heating wire with the mat or roll still connected to the power source.
Note
On rare occasions, a cable in a heating mat may break. When this occurs, it can be easily detected by using an instrument that functions as an underground fault detector. Repairing the break is simply a matter of locating it, removing the small section of floor above it, splicing the cable, and then replacing the flooring. As was already mentioned, the ground fault circuit interrupter is used to monitor electricity flow to determine if there has been any loss of current. If there has been a loss, the thermostat will cut off power to the heat- ing system until the problem is located and corrected.The GFCI on a programmable thermostat should be tested immediately after installing the thermostat, and once a month after the initial test to make sure the GFCI is continuing to operate properly. Testing instructions are provided by the manufacturer of the programmable thermostat.