While modern furnaces are much safer than older models, it’s still important to understand that problems may occur. Among those problems are gas leaks. Understanding why a gas leak might happen in a furnace can help you ensure your family’s safety if this problem should ever arise.

Causes of Gas Leaks in a Furnace

Cracks in the heat exchanger are the most common causes of gas leaks in a furnace. When there is a crack in the heat exchanger, it can lead to leaks in the gas supply line that runs to your furnace. Typically, gas combustion occurs in the chamber located inside the heat exchanger.

Air is then blown into the component in order for the heat to be picked up before the air is circulated throughout the ductwork. When the heat exchanger is cracked, it becomes possible for gas to actually escape before combustion can occur. When this happens, harmful fumes can be released inside your home.

Overheating is the primary cause of cracks occurring in heat exchangers. When there is not sufficient airflow to ensure heat is able to dissipate safely, overheating takes place. Several factors can lead to restricted airflow, including:

  • Duct blockages
  • Dirty furnace filters
  • Ductwork that is too small for the home
  • Air handlers or furnaces that are too large for the home

Gas Leak Warning Signs

Among the most common warning signs that your home may have a gas leak from the furnace is the smell. Natural gas actually has absolutely no odor. For safety purposes, the chemical mercaptan is added by manufacturers to natural gas so that leaks can be detected.

This addition results in a smell similar to sulfur or rotten eggs. If you notice an odor that smells like rotten eggs near your home’s furnace, ductwork, or anywhere else inside your residence, the cause could be a gas leak.

Gas leaks may also be detected by simply listening to your furnace. Due to the fact that gas becomes pressurized inside the device, you may be able to hear a hissing sound. This sound occurs as gas escapes from the furnace.

Gas Leak Hazards

Gas leaks inside your home pose serious health risks. While natural gas is actually considered non-toxic, it can cause suffocation by replacing the wholesome air in a confined space. It can also explode when a concentration of it encounters a spark.

In addition, like any carbon-based fuel, when it is burned with insufficient oxygen, incomplete combustion occurs. That is caused by a malfunctioning furnace, and the result is carbon monoxide (CO). This is a harmful substance when released into the air. It is toxic, and unlike natural gas that has been treated, it is odorless. When exposed to it, you may become quite ill. Some of the most common symptoms associated with exposure to carbon monoxide include:

  • Headaches
  • Nausea
  • Dizziness
  • Difficulty breathing
  • Sinus irritation

In some cases, carbon monoxide poisoning can produce more serious symptoms. Such symptoms may include concentration problems, fatigue, stomach and chest pain, loss of motor control, and vision problems. Extreme cases of carbon monoxide exposure may also result in loss of consciousness and possibly even death.

Steps to Take When a Gas Leak Is Suspected

Even if you have not noticed any symptoms associated with exposure to a gas leak, it is still a good idea to be proactive if you suspect one. The first step you should take is to shut off your HVAC system. Do not light any candles or matches.

To increase ventilation, open windows and doors. Evacuate everyone in your home from the area. Do not re-enter your home before getting in touch with your gas provider. You should not go back in until the leak has been handled.

It’s also a good idea to ensure your furnace is inspected prior to trying to use it again. An experienced HVAC technician can provide such an inspection, including a comprehensive test of your system. This test will detect any possible leaks and provide you with the necessary information regarding the need for possible repair or replacement.

Although furnace gas leaks are not common, it is important to know what to look for in the event of one. For more safety information or tips to ensure your HVAC system is working properly, get in touch with our HB Home Service Team in Harrisburg, PA. We cover the entire Central Pennsylvania area. You can count on our experts for a full range of heating, cooling, indoor air quality, plumbing, and electrical inspections, installations, maintenance, and repair. Call us today to discuss your needs or schedule service.

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