Macon, GA, is a fantastic city with many amazing things to see and do. If you live in the Macon area, you might own a gas furnace to keep your home warm during the chilly Georgia winter months. Sometimes, you might notice a yellow furnace flame instead of a blue one, but what does that mean? The experts at Ricky Heath Plumbing, Heating, and Cooling are here to explain what this color means, common causes, why it could be dangerous, how to fix it, and more.
What Your Furnace Flame Color Means
The color of your furnace’s flame can tell you a lot about the condition of the unit, and may explain why you’re having issues with your heater, such as some rooms being colder than others, a furnace that runs constantly, or a furnace that never hits the set temperature on your thermostat. Here’s a breakdown of the flame colors and what they mean:
- Blue: A blue flame burning consistently, without much flickering or movement, indicates complete combustion and a balanced air-fuel mixture. This means your furnace is burning efficiently and working as it should
- Orange: An orange furnace flame indicates incomplete combustion, possibly putting you at risk of a dangerous carbon monoxide leak. Contact a heating repair pro for help if you notice an orange pilot light.
- Yellow: A yellow flame is also a cause for concern, indicating that the fuel isn’t being burned efficiently. This can be caused by poor airflow, dirty burner elements, or a malfunctioning gas valve, and can be an early warning of problems ranging from gas leaks to pooling water around the furnace. You’ll need to have your furnace repaired or replaced if you notice a yellow flame.
- Green: Green flames are rare in furnaces, but they shouldn’t be ignored. Although a green flame is quite an interesting sight, this means there’s a purity issue with your fuel supply. Contact an HVAC service team right away to inspect the fuel supply and get your pilot light restored to a normal blue color.
What Color Should the Furnace Flame Be?
Your furnace flame should be blue, indicating a good air-fuel mixture and efficient fuel combustion. A blue light means the furnace will function properly, heat your home as much as possible, and run more efficiently. If your furnace flame is any other color, you should contact a professional for repairs or new heating installation right away to ensure your safety — especially if it's in conjunction with other issues, like a furnace making strange noises.
Common Causes of Yellow Flames on Your Furnace
There are several common causes of a yellow furnace flame and not all of them have a corresponding error code. These issues may occur separately, or several issues might occur at once. Either way, they typically require the help of an experienced professional to troubleshoot, diagnose, and repair.
Here are some of the most common reasons why your furnace flame is yellow instead of blue:
- Dirty burner: Dust, dirt, and other debris can enter your furnace’s burner. This buildup of contaminants may prevent the gas and oxygen from mixing properly and cause the furnace to create a yellow flame.
- Not enough oxygen: A dirty or clogged air filter or ductwork restricts airflow, which could cause your furnace to produce a yellow flame and overheat. The furnace burner needs an adequate air supply to function properly and prevent improper combustion.
- Gas regulator issues: A malfunctioning or broken gas regulator can cause incomplete combustion and a yellow flame.
- Contamination in the gas supply: Impurities like oil or moisture that get into your gas supply can create discolored flames.
- Malfunctioning gas valve: If your gas valve isn’t working correctly, it can’t regulate the flow of gas into the burner assembly. This irregular flow interferes with the balance between the fuel and oxygen required for a healthy blue flame.
- Flame sensor issues: A malfunctioning flame sensor may cause your furnace to struggle to maintain the correct temperature. This leads to higher gas consumption, lower efficiency, and a yellow flame.
- Rusted flue lines: If rust gets inside your flue lines, it causes poor venting. This often results in hazardous gases venting improperly.
- Heat exchanger issue: A cracked or clogged heat exchanger can prevent the gas from combusting fully and may create a yellow flame.
Why a Yellow Furnace Flame Can Be Dangerous
A yellow furnace flame can pose a serious health and safety risk. This color of flame is dangerous because it could lead to the production of carbon monoxide. This odorless, colorless gas is toxic when inhaled. A yellow flame increases the risk of carbon monoxide poisoning, which is potentially deadly. Breathing in carbon monoxide can cause headaches, dizziness, vomiting, confusion, and more.
Aside from releasing dangerous carbon monoxide into your home, a yellow furnace flame also poses a fire risk due to unburned gas accumulating and building up in the system. Gas is highly combustible and easily ignites with a small spark or flame, posing a risk to your property and your family’s well-being.
How To Fix a Yellow Flame on a Gas Heater
It’s important to monitor your furnace regularly to confirm the flame is blue instead of yellow. Getting regular furnace maintenance at least once a year, including a professional inspection, cleaning, and tune-up, is also recommended to keep you safe.
Here’s how to fix a yellow flame on a gas heater:
- Shut off the gas and electricity (if applicable) going to your furnace.
- Inspect the burner and clean it thoroughly with a soft-bristled brush or cloth to remove excess dust and other debris.
- Clean the flame sensor using the same method used to clean the burner.
- Depending on your furnace model, inspect the air intake shutters and adjust them as needed to change the air-fuel ratio.
- Verify you have proper ventilation and airflow by cleaning and opening your air vents, clearing blocked vents, and replacing dirty air filters.
- Read your furnace manual and check the gas pressure to confirm it’s at the proper level.
- If you haven’t already, install several carbon monoxide detectors in your home to help detect issues with your gas furnace before they become dangerous.
- After you follow these steps, turn the gas and electricity going to your furnace back on, turn the furnace on, and confirm the flame is now blue.
When To Call a Professional HVAC Technician
If you’ve already cleaned the burner and flame sensor, confirmed proper ventilation, and checked the gas pressure, but you still see a yellow flame, call a professional HVAC technician. Turn off your furnace and shut off the gas supply immediately.
Here are other instances when you should get help from a professional HVAC technician to fix this issue:
- Your carbon monoxide detector goes off: If your carbon monoxide detector sounds an alarm, leave your home immediately, then call your local gas company and a professional HVAC company to address the issue.
- You see an orange flame: An orange flame in your furnace is a warning sign of potential issues that could escalate to a costly breakdown. Call the experts at Ricky Heath as soon as you notice an orange flame to get prompt repairs before the flame turns yellow.
- You’re unfamiliar with furnace components: If you can’t locate the burner or other parts that need cleaning, it’s best to call an HVAC expert to perform a professional inspection and cleaning.
- Hissing noises: Sudden hissing sounds from your furnace usually mean a gas leak. This issue requires assistance from your gas company and possibly an HVAC technician.
Call Ricky Heath Today!
The experienced technicians at Ricky Heath Plumbing, Heating, and Cooling are available to help with your HVAC concerns. Whether you see a yellow furnace flame and need repairs, maintenance, or a new furnace installation for your Macon area home, we’re proud to serve you. If you’re interested in any of our services, including furnace service, contact us today!
