Water Heater Pilot Light: What Causes It to Go Out?


Water Heater Pilot Light: What Causes It to Go Out?

A malfunctioning or faulty water heater pilot light presents a major inconvenience for homeowners with gas-operated systems. There is nothing more frustrating than turning on the tap only to find there is no hot water. This is especially true when it is time to bathe. Many circumstances can cause your pilot light to malfunction or go out. Most pilot light malfunctions are directly associated with the thermocouple.

What is a Thermocouple?

Often, a malfunctioning water heater pilot light results from a problem with the thermocouple. A water heater thermocouple is a safety device designed to prevent the release of flammable gas, which could ignite and cause a dangerous explosion. A simple description of a thermocouple is two pieces of wire inside a protective covering. One end attaches to the thermostat while the other extends into the main burner with its sensory tip within the pilot light flame. As the pilot flame heats up, the thermocouple sends an electric signal that opens the appliance’s main gas valve. If the pilot flame does not produce enough heat or it goes out, the thermocouple cools off, the electric signal stops and the gas valve closes.

Dirty Thermocouple

A dirty thermocouple is the most common cause of malfunctioning water heater pilot light. Because the tip of the thermocouple is exposed to a direct flame, carbon can build up and cause the flame to malfunction or go out.

Bent Thermocouple

If the thermocouple is bent or not touching the flame, it will conclude that the pilot light is off or malfunctioning. The electric signal to the water heater’s gas valve will stop and the supply of gas to the appliance will cease.

Dirty Pilot Light Tube

The pilot light tube delivers the gas to the flame. The end of the tube sometimes experiences carbon buildup. When this happens, the tiny holes on the end of the tube clog and alter or extinguish the pilot flame. If you suspect your pilot tube is dirty or clogged, you should have it checked out immediately.

Damaged Thermocouple

Because of the extreme conditions thermocouples are subjected to and the sensitive nature of their design, they do burn out or malfunction. When this happens, replacement is necessary.

Although some of the cleaning and maintenance procedures for a gas-operated water heater might seem easy, it is recommended you hire an experienced and licensed plumbing contractor to service your unit.

For answers to your questions, contact the Pink Plumber today.

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