Our thermostat wires and cables feature premium PVC (polyvinylchloride) insulation and are available with a white or brown jacket. Our line of jacketed thermostat wire has annealed solid bare copper conductors in 20 and 18 AWG and a temperature range of -20ºC to +105ºC. Unjacketed options are also available to meet the demands of your application. Our thermostat wire is applicable in a wide variety of applications. These include thermostat controls, heating and A/C installations, remote controls, signal systems, intercoms, and various other low-voltage uses. Our Thermostat Cable is UL Listed Type CL2 and our 18 AWG collection is CSA Type LVT approved. 

Thermostat Wire Frequently Asked Questions

What gauge wire should be used for thermostat wiring?

18-gauge and 20-gauge wires are generally recommended for thermostat wiring. Smaller gauge wire is appropriate for thermostat wiring because this wiring generally carries a very limited amount of power which makes it suitable for low-voltage applications.

How many wires do I need for a thermostat?

The number of wires needed for a thermostat depends on the type of system you have and the features of the thermostat you are installing. A basic thermostat that would be used with an HVAC typically requires 4 wires (power, ground, heating, and cooling), but a more advanced thermostat may require additional wires. A more limited application, such as a thermostat to regulate a heater, may only require three wires, with one each for power, ground, and heating.

Can I use existing thermostat wire for new thermostat wiring?

If the existing thermostat wire is in good condition and has the correct gauge, it can usually be reused. The wiring should be inspected to determine its condition. If the insulation is cracked or compromised, the wiring should be replaced.

Is it possible to wire and install a thermostat yourself without calling a professional?

Yes, it is possible to wire and install a thermostat yourself, but it can be a complex process, especially if you are not familiar with electrical wiring. If you choose to do so, refer to the manual or consult a professional if you are uncomfortable doing so.

What happens if thermostat wire is not connected properly?

The system may not function correctly, or at all if the thermostat wire is not connected properly. This could lead to the heating or cooling system running constantly, or not turning on at all, which could possibly damage the HVAC system. If the incorrect connection led to either system running constantly, this could lead to increased energy costs as well.

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