Will Pilot Light Go Out If Gas Is Turned Off? (Explained)

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The pilot light should always be turned off before the main burner relight. However, the gas supply to the pilot light is shut off if the pilot light is out in some gas appliances.

burning gas from kitchen stove on background of stylish kitchen

What Would Cause Pilot Light to Go Out?

Most modern gas furnaces are lit by electronic ignition, but for older furnaces, your heating system is most likely to be started by a standing pilot flame.

As a small spark, a pilot light serves as a spark plug for a gas burner. Pilot lights going out are a common cause of furnace failure in older models. Is there a reason for this? See what causes a pilot light to go out.

Age of Heating System

There’s a pretty good chance you have a gas or propane furnace that’s 21 or older if it has a standing pilot light.

This system is so old it often means its parts and components have become dirty, worn, and unreliable over time; any combination of these elements breaking or failing can lead to a pilot light failure.

Cracked Heat Exchanger

Older heating systems are known for cracked heat exchangers, resulting in your pilot light going out. An air leak will alter the pressure in the combustion chamber and will affect the flame inside. If the crack is located somewhere inside the heat exchanger, air can blow onto the flame.

Gas Valve Issue

An uninterrupted supply of gas or propane is required to light the pilot light. In the event of a malfunction or dirty gas valve, this will result in the flame going out.

A low or no supply of gas may also lead to the flame going out. Occasionally, a pilot light may go out simply because wind or air blows it out. A problem with your flue pipe or your venting could be the cause of this.

Thermocouple Malfunction

The thermocouple lights your furnace pilot light on your heating system. Pilot lights behave like thermocouples when they are lit. The pilot light keeps the gas line open when lit by the thermocouple.

Thermocouples are dirty or malfunctioning and often turn the gas off in error, stopping your furnace and turning off the pilot light. When you know what is wrong with the thermocouple, you can fix it.

Before you begin to examine your furnace is to get a flashlight and a screwdriver. There will be a cover to remove, and the lighting will probably not be favorable.

When you’re trying to fix a busted furnace, the only thing more frustrating is the hundreds of trips to the garage to collect tools.

Turn off the gas flow and shut off the electricity to the furnace for safety reasons. Finding the thermocouple should not be a problem. You will need to find the end of a copper rod near the pilot light, a thermocouple.

Will Pilot Light Go Out If Gas Is Turned Off?

The pilot light may go out infrequently. It’s not uncommon for the problem to be solved simply by switching off the gas. A qualified service technician should examine the pilot light if it needs to be relit more than twice per season.

Is It Dangerous If the Pilot Light Goes Out?

There is a concern here that the gas valve that provides the pilot flame with fuel might still operate after a pilot goes out. Gas can build up and produce an explosion during the relighting of the pilot.

Modern times have made this a much less concerning occurrence. The shut-off valve on every furnace made within a reasonable time frame will be electric and failsafe.

As soon as the pilot goes out, this valve shuts off gas flow to avoid excessive gas buildup. As a result, even failsafe systems can malfunction, so always carefully check for gas odors when you have a malfunctioning pilot. Relight the pilot only if you don’t smell gas.

pilot flame gas boiler with wide angle

Working of Pilot Light

There are times when pilot lights burn out because of drafts or poor ventilation. A problem with the thermocouple on your appliance could be causing your pilot light to go out frequently.

When the pilot light goes out, a thermocouple protects your home from gas leaks. A thermocouple is cooled down and turned off when there is no flame on your appliance to heat it.

Pilot lights can be extinguished by faulty thermocouples or cannot be ignited at all. A thermocouple may have a problem, so you should consult with an expert.

You can easily relight the pilot light. However, you should never ignite a pilot light with gas nearby. You should report the gas leaks to your gas company right away.

When it comes to finding the pilot light on a water heater, it is not always easy. Under most water heaters, the pilot light underneath the tank is accessed by lifting an access cover.

By using a flashlight, you can find it more easily. Before lighting a pilot light, check the instructions that came with your water heater. Newer ones are replacing Old-style pilot lights. Instead of gas-fed pilot lights, most new appliances have electronic ignitions.

A good example of such an advance is the hot surface ignition system, controlled by an electrical current, and uses conductive metal to light your furnace in preparation for heating. As soon as the heating cycle has finished, the heater turns off, so there’s no need for a pilot light.

Many newer appliances have intermittent pilot lights powered by an electric spark rather than a small flame. In the long run, electronic ignition will take the place of conventional pilot lights.

Do I Need to Turn Gas Off If Pilot Light Goes Out?

Through the pilot tubing, a small amount of gas will leak. With the loss of pilot light, shut off the gas by activating the appliance isolation valve, which is usually located close to the appliance. You can then relight the pilot by following the manufacturer’s instructions.

Turning Off the Pilot Light

In most cases, the pilot light control, assembly, and lighting instructions are located on the unit’s front, making them easily accessible. For those unable to find the manufacturer’s instructions, follow the given steps.

  1. A pilot light assembly should include an “On,” “Off,” and “Pilot” gas valve, as well as a “pilot reset” button.
  2. Wait several minutes after switching the valve to “Off.”
  3. Put the valve into the pilot position and push the pilot reset button with a barbecue lighter.
  4. When the flames are strong and bright, hold the button down until the flames are lit, then let go and turn the gas valve to “On.”.
  5. You can rotate the gas valve to the “Off” position and contact service if the flame does not stay lit.


Age of the heating system, cracked heat exchanger, gas valve issue, and thermocouple malfunction are some prime reasons that can cause the pilot light to go out.

However, no matter what the issue is while dealing with the pilot light, you should be careful. If you don’t know much about pilot lights, you should contact a professional to help you with it, which will make things manageable for you.

Pilot lights require gas to operate. It can be dangerous to ignore safety when it comes to gas. You will want to carefully make sure there is no gas lingering in the air when you’re lighting a pilot.

If gas leaks, you should turn off all the gas valves near your pilot, open windows for ventilation, and wait until no trace of gas remains.

If you still smell any gas, you should avoid turning the pilot on to avoid any damage. A gas leak can cause serious damage; therefore, you should be careful while dealing with it.