How to Check if Heat Cable is Working

Checking if a heat cable (also called heat tape) is working properly is important to prevent freezing pipes or roof ice dams. Here’s how to verify its functionality:

1. Visual Inspection

• Check for physical damage (cracks, frayed wires, or burnt spots).

• Look for indicator lights (some heat cables have a small light showing power is on).

2. Touch Test

• For pipes: Feel along the cable (carefully—it shouldn’t be scalding hot). It should be warm to the touch.

• For roofs/gutters: Check if ice is melting where the cable is installed (after it’s been on for a while).

3. Use a Non-Contact Voltage Tester (For Plug-In Cables)

• Turn on the heat cable and hold the tester near the cord or outlet—it should detect voltage if power is flowing.

4. Check with a Multi-meter (For Hardwired or Suspected Faulty Cables)

• Unplug the cable and set the multi-meter to measure resistance (Ohms Ω).

• Touch the probes to the prongs of the plug (for plug-in cables) or the ends of the wires.

  • No reading (infinite resistance) = Broken circuit (cable is dead).

  • Low resistance (e.g., 10–100 Ω) = Likely working.

  • Zero resistance (short circuit) = Faulty.

5. Monitor Temperature with an IR Thermometer

• Point an infrared thermometer at the cable—it should read warmer than the surrounding area.

6. Check the Thermostat (If Applicable)

• Some heat cables have built-in thermostats that only activate below freezing (~38°F or 3°C). Test by cooling the thermostat (e.g., with an ice pack) to see if the cable warms up.

7. Test the GFCI Outlet (If Plugged In)

• Press the "Test" button on the GFCI outlet to ensure it trips, then reset it. If it won’t reset, the cable may have a short.

8. Look for Ice Buildup (For Roof/Gutter Cables)

• If installed on a roof or gutter, the cable should prevent ice dams. If ice persists, the cable may be faulty or poorly installed.

Safety Tips:

• Always unplug the cable before inspecting for damage.

• Never wrap heat cables over themselves—this can cause overheating.

• Replace old or damaged heat cables—they can be a fire hazard.

If you’re unsure, consult an electrician or the manufacturer’s guidelines. Let me know if you need help troubleshooting a specific type of heat cable!