How to Repair a Damaged SunTouch Heating Cable

Heating Cable Repair Kit

The SunTouch Heating Cable Repair Kit includes the components required to repair one damaged section of a radiant floor heating cable.

Depending on the repair method selected, certain components may not be required during installation.

Electrical Repair Tools

• Heat Gun: Must reach approximately 1000°F for proper heat shrink installation.
• Thermal Wire Strippers: Used for stripping heating wire insulation without damaging the internal conductors.
• Scoring Tool: Designed for carefully removing the outer cable jacket.
• Wire Strippers: Used for cutting and stripping 16AWG wire.
• Small Screwdriver: Helps separate heating wire from the braided shielding.

Electrical Test Tools

• Digital Multimeter: Must measure resistance up to 20,000 ohms for accurate cable testing.
• TDR Meter (Time Domain Reflectometry): Used to identify additional cable damage locations during diagnostics.

Additional Recommended Tools

• Hammer and chisel
• Hot glue gun with standard adhesive sticks
• Scissors
• Protective gloves

Heating Cable Construction

Depending on the installation type, the SunTouch heating cable may use one of two cable constructions.

Jacketed Heating Cable

This cable design contains two insulated heating wires protected by a tin-coated copper braid and an outer protective jacket.

Each heating wire contains multiple heating elements that must remain intact during the repair process.

Wire Color Reference:

• Black 4 / Brown 4
• White 4 / Yellow 4
• Red 3 / Clear 4
• Green 4 / Tan 4
• Orange 3 / Violet 4
• Blue 3 / Gray 4

Stainless Steel Heating Cable

This cable type uses two insulated heating wires protected by a stainless steel braid.

Tile and Mortar Removal

Carefully remove the tile, stone, or flooring material above the damaged cable area.

Use a grout removal tool or other blunt instrument to remove grout around the affected tile.

Do not use a knife because it may damage additional sections of the heating cable.

Gently remove the tile using a hammer and carefully clean away loose debris during the process.

Remove enough mortar and surrounding material to expose approximately 4 to 5 inches of free cable on both sides of the damaged area.

Carefully remove mortar around the cable using a hammer and chisel as needed. Mesh may be cut with scissors to free the cable safely.

Cut out the damaged section of the heating cable to create two clean wire leads.

This repair method is commonly used when sufficient cable slack exists to overlap the heating wire elements properly.

If your installation uses a jacketed heating cable, carefully score the outer cable jacket approximately 2 inches from the end of each lead using the scoring tool.

Rotate the tool only one or two revolutions around the cable. Allow the spring-loaded pressure of the tool to perform the cut.

Do not apply additional pressure while scoring the cable jacket to avoid damaging the internal heating elements.

Step C3: Bend the cable gently to loosen and remove the jacket section at the scored location.

Step C4: Using a heat gun set to approximately 1000°F, apply heat beneath the loosened jacket section for several seconds until the material begins to shrink slightly and loosen.

Step C5: Carefully remove the heated jacket section using gloves or protective cloth.

Warning: The heated cable jacket may be extremely hot and can cause burns.

Step C6: Push back the braided shielding approximately 1/4 inch to expose the heating wires inside the cable.

Step C7: Carefully bend the cable back on itself.

Step C8: Using a small screwdriver or blunt tool, gently separate the braided shielding and pull the heating wires through the opening.

Take care not to damage the internal wire insulation or heating elements during this process.

Step C9: Pull the braid tightly together to create a secure pigtail connection.

This grounding braid connection is important for maintaining proper system safety and cable shielding performance.

Step C10: Using thermal wire strippers, carefully remove exactly 1/2 inch of insulation from the heating wires.

Inspect the exposed heating elements carefully to ensure none of the internal strands have been damaged or removed.

The internal fiber strand does not need to be separated or removed.

Step C11: Before continuing the repair, test the cable using a digital multimeter and TDR meter to verify that no additional damage exists in the heating cable.

Testing both directions of the cable helps confirm the repair area is isolated and suitable for repair.

Step C12: Slide a solder tube over one of the exposed heating wires.

Step C13: Overlap and lightly twist the heating wire elements together before centering the solder tube over the splice.

Ensure the twisted wire elements remain centered between the adhesive bands inside the solder tube.

Step C14: Use the heat gun to apply heat directly beneath the solder ring until the solder fully melts and flows into the wire connection.

Continue heating for several additional seconds after the solder flows to ensure a reliable electrical connection.

After the solder melts, continue heating the remaining tube evenly until the adhesive seals completely around the wire insulation.

Allow the connection to cool completely before handling.

Step C15: Repeat the solder tube installation process for the second heating wire.

Step C16: Install the ground braid solder connection using the supplied ground solder tube.

Step C17: Heat the tube evenly until the solder flows completely through the braid connection.

Step C18: Once completed, the direct splice repair is ready for electrical testing.

Step D1: Remove a 2 to 3 inch section of damaged heating cable to create two clean cable leads.

If your installation uses jacketed heating cable, continue with the following preparation steps before installing the jumper splice.

Step D2: Carefully score the outer cable jacket approximately 2 inches from the end of each cable lead using the scoring tool.

Rotate the tool lightly around the cable one or two revolutions without applying additional pressure.

Step D3: Bend the cable gently to loosen and remove the scored jacket section.

Step D4: Apply heat beneath the jacket using a heat gun until the material loosens and slightly shrinks.

Step D5: Remove the loosened jacket carefully using protective gloves or cloth.

Step D6: Push back the braided shielding approximately 1/4 inch to expose the heating wires.

Step D7: Bend the cable back gently to prepare access to the internal heating wires.

Step D8: Carefully separate the braided shielding and pull the heating wires through the opening.

Step D9: Pull the braided shielding together tightly to create a secure grounding pigtail.

Step D10: Using thermal wire strippers, remove exactly 1/2 inch of insulation from the heating wires.

Inspect the exposed heating elements carefully to verify that no internal strands have been damaged during stripping.

Step D11: Test the heating cable using a digital multimeter and TDR meter before proceeding with the repair.

Step D12: Trim the black jumper wires to the proper length if necessary.

Step D13: Strip approximately 1/2 inch of insulation from both ends of the jumper wires.

Step D14: Slide a solder tube over one heating wire.

Step D15: Position the jumper wire alongside the heating wire elements and lightly twist them together.

Center the solder tube over the twisted wire connection while ensuring the wire insulation overlaps properly within the adhesive sections of the tube.

Step D16: Apply heat directly beneath the solder ring until the solder fully melts and flows into the wire connection.

Continue heating evenly until the solder tube shrinks fully and the adhesive seals tightly around the insulation.

Allow the splice to cool completely before moving the repaired wires.

Step D17: Repeat the jumper splice procedure for the second heating wire.

Step D18: Complete the splice connections on the opposite side of the jumper wires.

Step D19: Trim the ground jumper wire as necessary for proper fitment.

Step D20: Install the ground braid solder tube and complete the grounding connection.

Step D21: Repeat the grounding connection process on the opposite side of the jumper wire.

Step D22: Once completed, the jumper splice repair is ready for final electrical testing.

Step E1: Gently tug on each splice connection to verify the wires are securely connected and will not pull apart.

Step E2: Use a digital multimeter to measure the resistance of the repaired heating cable.

The measured resistance should fall within the acceptable resistance range specified for the heating cable model.

No resistance should be detected between either heating conductor and the green ground wire.

If resistance readings fall outside the specified range, inspect the repair for additional cable damage or incomplete splice connections.

Step E3: Connect the repaired heating cable to a properly protected GFCI power source, such as a compatible SunTouch or Watts Radiant floor heating thermostat.

Operate the heating system for several days or complete at least 10 to 15 heating cycles of approximately five minutes each.

If the GFCI trips or the cable fails to heat properly, the system should be inspected for additional cable damage or failed splice connections.

Before reinstalling tile or floor coverings, verify that the repaired splice lays flat and is properly protected within the floor assembly.

Step F1: If necessary, carefully carve a shallow valley in the subfloor beneath the splice connection using a chisel.

This helps prevent pressure points beneath the tile installation.

Step F2: Apply hot glue adhesive inside the valley and secure the repaired splice carefully into position.

Step F3: If flooring materials will not be installed immediately, protect the repaired area using a loose tile or other hard protective covering to prevent additional job site damage.