Gas Smell from Furnace

Why does gas smell from furnace? There are times when smelling this gas is nothing to worry about. Other times, you should be worried and shouldn’t wait to call a professional furnace repair.

Why does gas smell?

Natural gas doesn’t smell by itself. It also has no color or taste. A chemical called mercaptan is added to natural gas by companies that sell it. Mercaptan is an ingredient that has a bad smell. Even if there are only 10 parts per billion of it, your nose can smell it.

Some people say it smells like eggs, garlic, or rotting cabbage. Some people think it smells like skunk spray. All of these ways of thinking are right.

It smells like sulfur, which is a part of the compound. Sulfur is also in garlic, onions, cabbage, eggs, and skunk spray, which is why they all smell the same. Mercaptan is a natural substance that is made when the body breaks down food. It must be added to natural gas by gas companies so that a gas leak can be easily found.

Natural gas is very flammable and can hurt you if you breathe it in. So, if you smell gas coming from your furnace, you should take the right safety steps. Unless something is wrong with the furnace, you shouldn’t smell gas near it.

If you smell gas near the furnace while it’s running, you probably don’t need to worry. When running, gas furnaces can sometimes give off small amounts of gas. But you might need furnace repair if the faint gas smell gets stronger or stays around for a long time.

What to do?

If you smell strong gas or hear hissing coming from your furnace, turn off your furnace, leave your house, and call your local gas company right away. Do not turn on or off any lights or appliances, and do not light matches or cigarette lighters. Everyone should leave the house until you’re told otherwise.

There are gas leaks if you can smell gas near the furnace. If you smell gas near your furnace while you’re waiting for a professional to come fix it, you need to take action right away.

First, turn off the furnace using the thermostat and open the windows to get rid of the gas. You should also turn off the main gas supply to the heater and call a professional who can figure out what’s wrong and fix it. Here are some things that could cause a gas leak in a furnace.

When it’s normal for the furnace to smell like gas?

The gas supply valve lets gas into the combustion chamber when the thermostat starts a heating cycle. It only takes a tiny amount of time for the ignition or pilot to light the gas. At the beginning of the heating cycle, you may smell natural gas because it takes the burner a few seconds to burn off the first supply.

The smell should go away in a minute or two. This is how a gas furnace works most of the time. It’s nothing to worry about as long as the smell is faint, only lasts a short time, and stays close to the furnace.

Why furnace gas leaks happen?

There could be more than one reason why your furnace starts to leak gas. The following can cause a gas leak:

  • A cracked heat exchanger, which can happen when it gets too hot
  • Gas line is broken or cracked. This can happen if someone bumps into the gas line or furnace, or if something like a small earthquake shakes the house.
  • Ignition failure due to poor furnace maintenance.

There are a few other signs of a gas leak besides the smell of mercaptan that is added to natural gas. You might hear a hissing sound inside your home.

A hissing sound could come from the gas pipe if there was a gas leak. One or more of your gas-powered appliances may not work as well as they should. For example, your gas cooktop’s burner flames may flicker.

The grass outside your house may turn brown where the gas line is buried. Shrubs or flowers above the gas line may die and turn brown. You might hear something gurgle or bubble. If it has just rained, a puddle might have bubbles coming out of it.

Setting up a tune-up for your furnace once a year is the best way to avoid problems with the gas supply or the way it works. During a tune-up, a technicians look at the supply valve, thermocouple, burner, heat exchanger, combustion chamber, and air seal. They also check the chimney and the flame to make sure the furnace is burning the natural gas correctly.

A yearly inspection of the furnace looks for worn parts and other damage that could cause a gas leak. Putting in a carbon monoxide detector is another thing you can do. They look for carbon monoxide, which can leak from a furnace that isn’t working right. When there is a lot of carbon monoxide in the air, the detector makes a loud noise.

Once a week, look through the observation window in the combustion chamber to see what the flame looks like. The flame should stay steady and be blue. If it flickers or is mostly yellow, it may be a sign that the furnace needs to be looked at by a professional HVAC technician.

Did you notice gas smell from furnace? As we’ve seen, it could be normal and nothing to worry about, or it could be a very serious problem, like a gas leak. Better to be safe and call a reputable technician to check, figure out, and fix the problem.

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