Newer gas furnaces (since about 2010) do not have a traditional pilot light that burns all the time. Instead they use electronic ignition systems that light only as needed. Constant flame or “standing pilot”
Pilot lights were phased out about 20 years ago and replaced with electronic igniters, so if your furnace or appliance is that old or older it may incorporate a pilot light.
Most modern electric furnaces do not have pilot lights, especially if they're from within the last decade. Instead, they use a device known as a hot surface igniter to kickstart the heating cycle.
What started to replace standing pilot lights in the 1980s is electronic ignition systems. Rather than keep a flame burning throughout the winter, furnaces with electronic ignition only need a brief bit of electrical power to light the burners—a minuscule use of energy.
This is something you can easily check by looking at your furnace to see if you see a constant flame even when it is not currently running. You can also open the access door to look for a pilot control knob. If you don't see a control knob or a flame, it means that your furnace doesn't have a standing pilot light.
If your furnace is a couple of decades old or older, it's likely that it has a pilot light. One way to check is to look for a round knob on the gas valve with the words Off/On/Pilot.
Newer gas furnaces (since about 2010) do not have a traditional pilot light that burns all the time.
Like an extinguished pilot, a faulty ignitor prevents a furnace from heating up. Unlike pilots, electronic ignitors cannot be manually lit when they fail. However, a homeowner can take troubleshooting measures to determine if the ignitor is bad or if some other issue is causing the furnace not to blow hot air.
The key distinction lies in their application: the thermocouple is a fixture in older furnaces with a continuous pilot light, while the flame sensor is a feature of newer, electronically ignited furnace models.
Pilot lights can also develop problems that cause them to burn inefficiently. When this happens, a small amount of carbon monoxide can be released into your home. Most gas appliances today rely on electronic ignition instead of inefficient pilot lights.
The pilot light is usually located near the bottom of the furnace, near the front. It may be hidden behind a small access panel. On some furnaces, the pilot light will be visible through a small window on the front of the furnace. If you cannot find the pilot light on your furnace, consult your owner's manual.
A fireplace pilot light might consume about 24,000 BTU per day, adding up to about 720,000 BTU a month, or 7.2 therms. If you're paying $1 per therm, then leaving the pilot light on all the time throughout a month might cost you around $7 per month and $84 per year. This may or may not be a concern for you.
So basically your pilot light is responsible for combusting your fuel source, which is how your furnace creates heat. If it goes out, the safety features of your furnace will not allow it to release gas into the burner, meaning that the furnace will not run at all.
One of the best things about high-efficiency furnaces is their electronic ignition technology, which eliminates the need for a pilot light. The main advantage of this technology is that you save energy because the pilot light isn't constantly burning.
In the end, keeping the gas fireplace pilot light on or off is a personal preference. The decision boils down to residual heat, gas usage, and the possibility of nesting spiders. Generally, we recommend turning off the gas pilot light during the summer months.
All gas boards provided the numbers of gas lamps running and the numbers replaced or out of use from war damage over a period of years. This was used to indicate the percentage reduction that could then be applied looking forward. Given a shortest and longest time, the eventual year considered was 1968.
1. Will a furnace run without a flame sensor? No, a furnace will not operate without a flame sensor.
Remove the small door on the front of your furnace. In some cases, a sticker with the manufacture date will be on the inside of the door.
This type of pilot light can be replaced with an automatic electric ignition that ignites the pilot only when the thermostat calls for the furnace to be fired. Many companies make pilot ignition retrofit systems that can be easily installed by skilled technicians.
Defective Igniter or Pilot Light
If it clicks but your furnace won't ignite after the combustion cycle, the electronic ignition systems probably need to be replaced. In cases where the furnace ignition starts normally but only stays on for a few minutes and then goes out, a new pilot light likely needs to be installed.
The Average Furnace Lifespan
A well-maintained furnace can last at least 15 to 20 years, but completing annual maintenance and being diligent with repairs can extend its life even longer.
They've become so identified with home furnaces that people take for granted that pilot lights are still around doing the same job as usual. This isn't the actual situation, however. Although you can still find gas furnaces with standing pilot lights, they have mostly gone of out use since 2010.
Electronic ignition is a device that replaces conventional pilot lights in almost all newly manufactured furnaces. There are two types of electronic ignitions: a hot surface ignition and an intermittent pilot.
With a furnace blowing cold air, the first question you should ask is if the furnace has been turned ON. Two thermostat issues that could cause your furnace to blow cold air include (1) your thermostat is still set to COOL, not HEAT and (2) your thermostat fan is set to ON, not AUTO.