Installing WarmWire® radiant floor heating includes a few important steps: understanding what’s included in your kit, preparing the space, installing the heating cable, placing your floor covering, and setting up your thermostat. Before beginning, take time to read the full installation manual. It explains safety requirements, electrical codes, spacing rules, and testing procedures, which are all essential for a safe and successful install.
What’s Included in the Heating Kit
Each heating kit contains the essential components needed for installation:
- WarmWire® heating cable
- LoudMouth® monitor
- SunTouch® thermostat
- Cable strapping
- Small roll of tape
- Installation manual
Planning & Preparation
- Before laying any wire or cutting into anything, read the manual from start to finish. It outlines safety codes, spacing requirements, testing procedures, and room-specific exceptions.
- Next, pick a location that is open and accessible for your thermostat. You’ll need to run a dedicated power line to the thermostat box, following all local electrical and building codes.
- Drill holes through the bottom wall plate for the conduit. You will need:
- One conduit run for the WarmWire® power leads
- One conduit run for the SunStat® floor sensor
- Install a 4×4 electrical box with a single-gang mud ring at thermostat height.
- Before installing any heating elements, conduct a cable and sensor resistance test using a digital multimeter to ensure there’s no damage to the product. To conduct these tests, see our article: How to Use a Multimeter to Check a Heating Mat or Cable.
- Vacuum and sweep to remove dust and debris.
Installing the WarmWire® Heating System
1. Feed Leads & Sensor to the Thermostat Box
Push the power leads and sensor wire through the conduit up to the thermostat location.
2. Connect to the LoudMouth® Monitor
Attach the WarmWire® cable to the LoudMouth®monitor. The LoudMouth® will sound an alarm if the cable is ever cut, crimped, or damaged. If you’re using multiple coils, connect them in series through the monitor.
3. Install Cable Strapping
Use spray adhesive, nails, or screws to secure the metal strap to the floor.
Note:
- Do not span more than 4 feet between strap runs.
- Add more strapping as needed for turns or tight areas.
4. Handle the Splice
The pre-made splice must never be bent. If needed, chisel a shallow recess into the subfloor so the splice sits flush and secure it with hot glue.
5. Route the Cable
Starting at the thermostat side, create a small stress-relief Z-loop. Each vertical tab on the strap equals 1 inch. Bend tabs over the wire to keep it in place and secure.
Note:
- Never route the cable under cabinets or fixed furniture.
- Maintain a 4–6 inch gap between the cable and walls, vents, and toilet rings.
- If the cable runs long, route excess around the perimeter within the spacing guidelines.
- Never cut the heating cable.
6. Place the Floor Sensor
Position the sensor between two heating runs, parallel to the cable. Never cross the sensor over the heating cable. Secure the sensor with hot glue.
7. Retest All Electrical Values
Perform another resistance test on:
- The WarmWire® cable
- The ground
- The sensor
Record all values, then reconnect the LoudMouth®monitor.
Installing Floor Coverings
Apply a latex-modified thin-set (3/8” thick) using a plastic or cable-safe trowel. For laminates, hardwood, or carpet, use self-leveling mortar instead.
Note: The heating cable must be fully enclosed in the mortar before covering.
After the mortar or leveling compound is installed, perform the final resistance test and record the results.
Installing the Thermostat
Follow these steps to install the SunTouch SunStat® thermostat:
- Remove the faceplate carefully (avoid bending the connector pins).
- Shorten the heating cable leads only if needed (keep at least 8 inches).
- Connect the load wires from the heating cable to the thermostat.
- Connect the line (power in) wires from the breaker.
- Attach the floor sensor to the sensor terminals.
- Secure the thermostat base to the electrical box.
- Reattach the faceplate.
- Briefly power on the thermostat to confirm everything is functioning correctly.
Note: Do NOT run the heating system until the thin-set is fully cured. Follow the mortar manufacturer’s cure-time guidelines.
If any complications arise, see our article: Troubleshooting SunTouch SunStat® Thermostats
Congratulations! You’ve successfully installed your WarmWire® floor heating system. Once your mortar has fully cured, you can turn on the system and enjoy warm, comfortable floors.
Warm Your Floor is Here to Help
For additional support or questions you have, contact our team and one of our experts will reach out to assist you in any way we can.
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