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Relighting Gas Furnace

All There Is to Know About Relighting the Gas Furnace

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The chilly winter weather is not the right time for your furnace to break, but sometimes, it does. Modern furnaces have a burner that is either ignited electronically or with a standing pilot flame. Typically, older furnaces with an annual fuel utilization efficiency rate of 80% or less are ignited by the standing pilot flame. If your furnace was manufactured after approximately 2010, it will not have a pilot light; it has an electronic ignition system that is only activated when it’s needed.

The gas furnace standing pilot is also referred to as “the pilot light.” This is a small blue flame used to light up the natural gas from the main burner. It is this pilot light that keeps the burner lit all the time.

The standing pilot serves the purpose of igniting the gas burner. When a gas furnace begins to work, the thermostat signals gas delivery from the valve to the burner. As it flows, the standing pilot ignites the gas before it reaches the combustion chambers. When the standing pilot fails to work as expected, the gas is not lit, and therefore, the gas furnace has an operational failure.

There are many reasons why the pilot lights go off, leaving the homeowner in the cold. They include thermocouple malfunction, draft, and a weak burning flame. A typical flame is blue, and if it changes to yellow, there must be a reason why the burner is burning inefficiently. The thermocouple usually detects this kind of inefficiency, and it shuts off the gas valves.

Fortunately, the pilot light going out does not necessarily require costly repair. In fact, the homeowner is in a position to relight their heating systems pilot light easily and safely on almost all gas furnaces.

How to Relight the Furnace’s Standing Pilot Light?

It is common for older furnaces to go out, but it’s way more frustrating when you do not know how to relight it. The process is not complicated, but it differs slightly depending on the pilot’s valve type and the furnace model. It’s vital that before attempting to relight the stove you should first consult the instruction manual customarily found inside the furnace door cover.

There are two model types of pilot. One has a valve knob on its body assembly. This knob is either pressed down or depressed when lighting. The other pilot model has a gas valve with a red reset button. These two model types have the same procedure of relighting if the pilot flame goes out. As long as your furnace is the older model and has a standing pilot, here is the standard relighting procedure.

Gather Materials and Tools

To relight the pilot light, you need to first gather the necessary tools. You will require a long-handled match or lighter. If you can’t find the appropriate lighter, you can roll up a sturdy piece of paper or cardboard to use instead.

Read the Instructions Manual From the Manufacturer

Furnaces come with a prominent label with instructions on how to relight the pilot light. This label may not be easily visible because heating units are generally found in dark garages or basements. Take a flashlight to assist you with the instructions. If your furnace does not have the label, look for the manufacturer’s manual that came with the system and read the instructions. Still, if you can’t find the instructions, you can log on to the company’s website for the relevant information.

Turn the Gas Off

Almost at the bottom of the furnace, you will find a switch that has the settings “Pilot,” “On,” and “Off.” Find the switch and turn off the gas by turning it to the “Off” position. Give the gas between three to five minutes to dissipate. This is critical because if the gas does not dissipate it could start a fire. While you wait, take note of where the reset button is located, which is most often found near the switch you turned “Off.”

Find the Nozzle and the Pilot Tube

The nozzle and the pilot tube are located inside the furnace next to the gas burner tube assembly. Please find it and also have your lighter ready. The pilot is sometimes hard to reach, and therefore, it’s advisable to use a long fireplace match as you light it. You can also use a butane barbecue grill lighter. If that is not available, you can also fasten a match to a stick and light the pilot.

Set the Valve to Pilot and Light the Standing Pilot

Set the gas valve to pilot from “Off.” Place the ignited lighter or the lit match on the pilot’s tip, depress, and hold the knob or the reset button. Keep pushing the knob or button for about 30 seconds to maintain the gas flow until the thermocouple is hot enough to trigger the opening of the main gas valve.

Set the Gas Valve Back to “On”

If the pilot stays lit, release the knob or the button slowly and turn the gas knob from the pilot position back to “On.” This will ignite the burners and keep steady the gas flow supply to the burners.

Upon ignition of the furnace burners, regulate the thermostat to the appropriate settings. If the burner does not ignite, the reason could be that the thermocouple did not get heated enough to open the gas valves. Wait for some time and then replicate the same procedure. This time, hold down the reset button for about 60 seconds.

If, after following the procedure for relighting the furnace more than twice and the pilot light won’t stay lit, something is wrong with the furnace, and you need to enlist a professional’s assistance.

A healthy-looking flame should be blue with a tinge of yellow at its tips if the furnace runs on natural gas. If it runs on propane, the flame should be bluish-green also with a yellow touch at the tip.

A Partner You Can Trust

Suppose the fire furnace cannot relight at all. You must contact a professional HVAC specialist to get it checked. At One Stop Heating and Cooling, we have a team of skilled technicians that offer you service with a difference. We schedule our visits when it’s most appropriate for you and strive to keep you as comfortable as possible.

One Stop Heating and Cooling is a locally owned and operated company that has been providing all of the residents of Sandy, Utah, with great heating and cooling services since 2017. We are a Better Business Bureau-accredited and EPA-certified company. Other than heating and cooling services, our company offers various other services, including duct cleaning, indoor air quality services, AC installation, maintenance, and repair among others. While our technicians are extensively trained to fix Amana products, we can service any model of furnace or AC. For more information on our services and discounts, contact us today.

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