What Is a Gas Fireplace Thermocouple?

A gas fireplace thermocouple is often found among contemporary gas fireplaces. A thermocouple is an electronic safety device. It is used for ensuring safety of the ignition system and preventing fuel leakage.

Understanding Fireplace Thermocouples

Most gas fireplaces have a start-up mode to allow heating of the thermocouple. During this mode, the gas should not flow into the burner. This can cause gas-leakage. All gas fireplaces have a safety pilot system that includes the thermocouple and a combination valve.

Working of Fireplace Thermocouples

A thermocouple is made up of two wires, each made of a different metal. The junction of these wires generates a small electrical voltage. This voltage varies with the temperature that the thermocouple is exposed to. When the required temperature is achieved, the voltage in the thermocouple causes the accompanying valve to open. This ensures that gas isn’t directed towards the burner until the required temperature is created for safe ignition.

Safety of Gas Fireplace Thermocouples

Gas fireplace thermocouples are completely safe for domestic use. Most factory-built fireplaces are rigorously safety-tested. Most of them are retailed with warranties and offers years of maintenance-free performance.

Prevalence of Gas Fireplace Thermocouples

Majority of gas fireplace thermocouples are found among Direct Vent (DV) fireplaces. They have a fixed, glass front which seals the gas burner and the combustion firebox. Here, most of the air used by a fireplace enters through a coaxial pipe, called the vent. This is a smaller pipe inside the larger, fireplace exhaust pipe that eliminates all combustible gases. Use of a direct vent helps to maintain indoor air quality.