Is my furnace going to explode?

Author: Dahlia Hayes  |  Last update: Sunday, April 13, 2025

The pilot light should be blue and have a steady, constant flame. An orange or yellow flame that flickers means pilot light issues – and is one of the signs your furnace is going to explode. The blue flame means that carbon monoxide safely exits the furnace system.

What would cause a furnace to explode?

A furnace explosion is usually the result of ignition and instantaneous combustion of highly flammable gas, vapor, or dust that has accumulated in a boiler. The effect of the force from the explosion is often much greater than the boiler combustion chamber can withstand.

How common is a furnace explosion?

Although it is possible for a gas furnace to either catch fire or explode, it's highly unlikely. If there is a danger of this happening, the furnace will usually simply shut off—as it's designed to. Regular maintenance will further reduce this already unlikely event.

When should I worry about my furnace?

You should be concerned if your furnace makes strange noises, blows cold air, cycles on and off frequently, or significantly increases your heating bills. Also, if it's over 15 years old and requires frequent repairs, it may be time to replace it.

How do I make sure my furnace is safe?

Gas Furnace Safety
  1. Have your furnace cleaned and checked every year by a NATE-certified technician. ...
  2. Install a carbon monoxide (CO) alarm in your home.
  3. Change your furnace filter regularly. ...
  4. Keep the area around your furnace clean and unobstructed.
  5. Keep the burner area of your furnace clean.

Signs Your Furnace is Going to Explode

How do you know if your furnace is emitting carbon monoxide?

Warning Signs of a Furnace CO Leak
  • Heavy condensation on the windows (found in the room with your furnace)
  • Yellow or brown soot-like stains found around your furnace.
  • A yellow pilot light (instead of a blue flame)
  • Stuffy indoor air.
  • The smell of gas/burning.
  • The pilot light constantly blows out.
  • Rust found on the vent pipe.

How safe are gas furnaces?

Besides gas leaks, an unmaintained gas furnace can also become a serious fire hazard. Any broken or malfunctioning parts will not work properly and may ignite. If dust and dirt is allowed to build up in the unit, the debris can catch fire.

How do I know if my furnace is overheating?

Watch for the following signs that indicate your furnace is overheating.
  1. A constant burning aroma.
  2. A strange humming noise.
  3. The furnace turns off before finishing a cycle.

Can a bad furnace cause a fire?

As reported by the National Fire Protection Association (NFPA), heating systems like furnaces are a leading cause of home fires, causing almost 50,000 blazes, 500 civilian deaths and more than $1 billion in significant property damage every year.

What is the average life of a furnace?

How long does a traditional furnace last? An average furnace is designed to operate for 15 to 30 years in a home. The easiest way to increase the life cycle of your furnace is to hire a certified technician to perform maintenance and repairs once a year.

What are the odds of a house exploding?

buildings are presented. concluded that in the USA the probability of occurrence of an explosion capable of causing significant structural damage could be 2.2 per million housing units per year.

Why is my furnace making an explosion noise?

If your furnace makes a booming sound when it starts up, this is usually due to what HVAC specialists call “delayed ignition”. Unfortunately, delayed ignition should never be ignored as it can cause severe damage to your furnace and even your family if left unaddressed.

How to tell if a furnace is bad?

Strange Noises

Many healthy furnaces will maintain a consistent whirring sound, which is handy in letting you know that it's in good working order. If you begin to hear strange noises—banging, rattling, irregular hums, groans, rattles, etc. —then that could mean that there's something wrong with the furnace.

What does it mean when your furnace pops?

Homeowners often notice a popping sound when the furnace begins a cycle. This is due to warm air that hits the cold metal of the ducts, which causes expansion and produces that noise. When the popping noise is louder, your gas furnace's burners may be dirty.

How much is a new furnace?

Ask twenty professional HVAC contractors the question, “How Much Does A New Furnace Cost?” and you'll probably get the same answer... “It depends.” On average, the cost of a new furnace can range from $2,000 - $14,2001. However, factors like furnace efficiency, type, size, and much more can impact this range.

How do you know if your furnace is dying?

Here are ten red flags you need to look out for to tell if your furnace is dying:
  • Frequent Service Calls. Constantly having to repair your furnace may be the first sign that it's failing. ...
  • Flu-Like Symptoms. ...
  • Strange Noises. ...
  • An Old Furnace. ...
  • Dry Air. ...
  • Flame Color. ...
  • Poor Temperature Control. ...
  • Higher Utility Bills.

Is it normal to see fire in your furnace?

Worn-out or frayed wires can create short circuits, leading to sparks or even fires. Another potential risk is a malfunctioning ignition system. If the ignition system fails, it may cause gas to build up in the furnace before igniting, resulting in a dangerous explosion or fire.

What fails first on a furnace?

If the flame sensor fails, your furnace may not be able to start or may shut down shortly after starting. Common causes of flame sensor failure include corrosion, dirt buildup, or a broken wire. The gas valve controls the flow of gas to the furnace. If the gas valve fails, your furnace won't be able to produce heat.

What does it mean when your furnace smells like it's burning?

Furnaces that overheat may shut down since the units contain internal limit switches that trip to protect the internal components. When furnaces overheat, the system can create a burning smell.

Will a furnace shut off if it overheats?

All modern furnaces have a furnace limit switch. The switch, which works in tandem with the blower to ensure the appliance is at a safe temperature, will turn off the burners if the temperature gets too hot, only letting them start again when it's safe to do so.

Should my furnace be hot to touch?

Because of the heat generated by the furnace, it's normal for the surface to feel hot, especially near the burners. However, if the furnace feels hot and you're experiencing heating issues in your home, it may be a sign that you need furnace repairs.

How do I know if my furnace is making me sick?

Symptoms of Heater Sickness

Here are a few common symptoms to keep an eye out for: Coughing and sneezing. Sinus infections. Allergy symptoms.

Is it safe to leave a gas furnace on overnight?

Leaving your home's furnace running day and night is expected and fully safe to do. However, many homeowners also use alternative heating systems, including space heaters and electric heaters, which are not safe to use when unattended (like at night).

How long can you run a gas furnace?

In rare cases, it can last more than 40 years, but the average lifespan tends to be between 15 and 30 years. With regular maintenance by a certified HVAC technician, there is no reason your furnace should not go above and beyond the 15-year mark.

Are gas furnaces being phased out?

By 2030, the California Air Resources Board (CARB) has banned the sale of new gas furnaces and water heaters. This is an effort to push homeowners toward zero-emissions alternatives like electric furnaces, heat pumps, and electric water heaters. This initiative shows California's commitment to combating climate change.

Previous article
What does a compressor burnout smell like?
Next article
Do throwing knives one shot in Sea of Thieves?