Gas Furnaces: 4 Problems That Can Turn Dangerous if Ignored

Natural gas is the fuel of choice for most homeowners. It is affordable, clean, and more efficient than other forms of fossil fuel. A gas furnace also consumes less energy to heat the same amount of space as an electric furnace. This is because an electric furnace takes more time to heat a series of coils.

Cafco Services, one of the leading heating and air conditioner maintenance companies in the area, discusses more here.

Gas Furnace Benefits

One of the many benefits of natural gas is it can reduce your heating costs by 50% to 70%. This depends on the efficiency of your furnace and the energy you are switching from. Gas heat also delivers warmer air than your body temperature, resulting in a toasty and comfortable home during the fall and winter months. In addition, gas appliances will continue to operate even in the event of power failure.

Another sought-after benefit of natural gas is that it is a cleaner type of burning fuel, making it less harmful to the environment than oil or electricity produced from fossil fuels. Using gas for home heating decreases the overall demand for electricity in your region.

Gas Furnace Problems

You can expect to get 15 to 20 years out of your natural gas furnace as long as you perform routine care and maintenance. However, an issue might still present itself occasionally, and some pose a more serious threat than others. Call for an immediate HVAC repair once you see any of these gas furnace problems:

1. Incorrect Gas-to-Air Ratio: Your furnace does not burn pure natural gas. Instead, it uses a mixture of natural gas and oxygen. The proportions of the mixture must be right for the fuel to burn safely and cleanly. When the ratio of gas to oxygen is off, your furnace creates more pollution as it burns fuel. This results in orange flames — as opposed to blue flames — and soot-like stains on the equipment. It can also encourage delayed ignition, which can cause a small explosion whenever your furnace starts up.

Other effects of an incorrect gas-to-air ratio are more difficult to detect. For one, it makes your furnace less energy-efficient, which takes a toll on heating costs over time. Even worse, your furnace will produce more carbon monoxide, an invisible and odorless gas that makes thousands of people sick every year.

2. Delayed Ignition: If your furnace makes a loud noise when it starts up, there is a good chance it has an issue called delayed ignition. It occurs when the furnace has gas, but the burners are not igniting. This causes the gas to accumulate inside the combustion chamber, and when it finally ignites, it creates a small explosion.

Delayed ignition is not safe for a few reasons, says an HVAC repair specialist. One, it puts an unnecessary strain on your furnace, causing its components to break down prematurely. A buildup of flammable gas is also severely hazardous as you could get injured by a flash fire if you were to attempt to manually relight the pilot light.

3. Cracked Heat Exchanger: Because furnaces burn fuel to generate heat, byproducts that are harmful to breathe — such as carbon monoxide — are created. To keep the occupants safe, the combustion process is sealed and separated from the air that is distributed around the home. The component that stands in the middle transferring the heat from one place to another is called the heat exchanger. The combustion process heats this component on one side and the breathing air blows over to the other side, which prevents the air from mixing with soot, carbon monoxide, and other poisonous gases.

However, a problem sometimes occurs when the heat exchanger cracks due to corrosion or overheating. One reason for this is an air filter that has not been cleaned or replaced in a long time. A crack that is wide enough can allow toxic gases from the combustion chamber to mingle with the air. Even if the concentration of these gases is not fatal, HVAC installation companies want you to keep in mind that low concentrations of these gases can still cause long-term adverse health effects.

4. Faulty Thermocouple or Flame Sensor: An older gas furnace with a standing pilot light has a thermocouple, a device that detects whether the pilot light is lit or not, whereas a newer gas furnace has a flame sensor instead. Albeit different in names, a thermocouple and flame sensor serve the same purpose — to prevent an unsafe buildup of gas inside the combustion chamber. A defective thermocouple or flame sensor could result in your furnace accumulating a dangerously high concentration of flammable gas. Once that gas is ignited, it could create an explosion.

According to HVAC installation companies, if your equipment features a standing pilot light, the thermocouple’s tip should be oriented in the direction of the pilot light flame. So if the pilot light goes out, the thermocouple will be able to detect the change in the temperature and shut off the gas valve.

If your furnace operates via electronic ignition, on the other hand, it will either use an intermittent pilot light, which flares up once the furnace starts heating, or a hot surface ignition, which utilizes an electrical device that gets hot enough to spark the gas and then shuts off.

In the newer models of gas furnaces, the function of the flame sensor is to ensure the burners have ignited. Once the sensor notices a problem with the ignition, preventing the burners from lighting, it immediately shuts off the gas supply.

Contact Cafco Services for All Your Heating and Air Conditioning Needs!

Do not let a minor HVAC problem spiral out of control. Turn to one of the premier heating and air conditioner maintenance companies in Ohio. You can count on Cafco Services for all your heater and furnace needs. Our certified technicians are dedicated to providing our Cincinnati customers with industry-leading products and services. So whether you need a simple tune-up, routine maintenance, or a new installation, we can help. Call us all at (513) 242-3400 or complete our convenient online form to schedule an appointment.