Modern furnaces have built-in safety features that include giving error codes that can aid in diagnosing a new problem. Homeowners often get stuck trying to interpret the blinking lights because the patterns can be hard to detect. Plus, you may find some variance in the flashing lights among the different furnace brands.
In this guide, you’ll learn how to check the error code to see if it indicates a quick fix or the need to call one of our professional technicians.
Quick Takeaways
- Furnace error codes are simply diagnostic signals the control board sends out.
- The majority of error codes show up as blinking LED light patterns
- The sequence and number of flashes matter.
- Error codes often point to issues that include airflow problems, safety shutdowns and ignition failure.
- Some issues are safe for DIY checks, but others require professional heater repair.
What Furnace Error Codes Are and Why They Matter
In modern furnace systems, there is an electronic control board that constantly monitors essential functions. For instance, the control board checks the ignition, blower motors and pressure switches.
If it detects a fault, then it will display flashing lights as an error code. Some systems display a two-digit code.
Modern furnaces also tend to shut down instead of powering through an issue. This is to help protect against major damage to the furnace. Plus, it ensures your safety, since some issues could lead to hazardous electrical problems or house fires.
Where to Find Furnace Error Codes on Your Furnace
Finding the furnace error code is a simple process when you use these steps to take a look:
- Remove the access panel
- Look for the control window or the LED display indicator
- Check the owner’s manual, if you cannot see a visible display
- Contact a professional HVAC tech for further assistance.
How to Read Furnace Error Codes (Blinking Light Patterns)
If you notice a steady light, then take it as a good sign that all is working well. While you might still need to call a technician to check on odd noises or other warning signs, steady lights indicate the control board isn’t detecting anything wrong.
Meanwhile, a blinking light is an indicator of an error code. You can usually identify the meaning of the code by looking at these attributes:
- Number of flashes
- Pause timing
- Repeating sequences
How to Count Blinking Furnace Error Codes Correctly
People often miscount furnace error codes due to rushing through the process of observing the flashing lights. Make sure to watch the error code for several seconds.
Sometimes, you can reset a furnace error code if you’ve already fixed a simple issue, such as changing the air filter. A quick reset could also recalibrate the system if you suspect it was a temporary glitch.
Common Furnace Error Codes and What They Usually Mean?
Error codes might vary slightly from one brand to the next, but you’ll typically see some similarities that can help you decipher the flashing lights.
- Ignition failure codes – Two flashing lights
- Pressure switch errors – Nine flashes
- Limit switch and overheating codes – Four flashing lights
- Flame sensor issues – Seven blinks
- Airflow and filter-related codes – Three blinking lights
- Electrical or control board faults – 10 flashes
What You Can Safely Check Before Calling for a Heater Repair
As a homeowner, you can check for a few common issues that are simple to fix.
- Make sure the thermostat settings are correct
- Check for a dirty air filter
- Inspect for obvious vent blockages
- Look at power switches and breakers to see if they are on
Keep in mind that you’ll want to avoid touching anything electrical or that could be potentially hot. Avoiding gas lines is also important for your safety. If the quick checks we’ve mentioned above don’t help, then give our friendly technicians a call.
When a Furnace Error Code Means You Need Professional Repair
Viewing error codes as early warning signs of a problem helps you avoid delays in arranging for repairs. Pay attention to these signs that calling for professional services now is important.
- Repeated lockouts
- Safety-related shutdowns
- Gas, control board, or ignition errors
- Codes returning immediately after a reset
Heater repairs are preventative and not reactive approaches to error codes that can preserve the system and protect your safety.
Why Furnace Error Codes Keep Coming Back
Clearing a code feels like a major accomplishment, but all of your stress can rapidly return when the flashing lights show up again. Usually, we can narrow this down to the following issues:
- Underlying mechanical failures
- Short-cycling issues
- Aging components
- Improper previous repair work
FAQ: Furnace Error Codes Explained
How do I know what my furnace error code means?
Counting flashing lights and noting patterns can help you decipher furnace error codes.
Are furnace error codes the same for every brand?
You may find some variance among furnace brands, but they are usually listed in the owner’s manual or near the access panel.
Can I reset a furnace after an error code appears?
You can reset the furnace when you know that the error code may be from a glitch or recent maintenance, provided that it is not gas, electrical or ignition switch related.
What is the most common furnace error code?
The most common furnace error code tends to indicate failed ignition with one to four blinks.
Is it safe to keep resetting my furnace?
Returning error codes is usually an indicator of more serious furnace issues that could pose a safety hazard. After doing one reset, it is best to call for professional help to figure out the cause of the error codes.
Schedule Expert Heater Repair for Furnace Error Codes
A professional diagnosis is important for making sure that the error code leads to the right solution for furnace problems. Calling our team as early as possible can help prevent major shutdowns when you need heat the most and ensure your safety. Plus, we’re always on time or you won’t pay a dime.
At Tampa One Hour, we provide heater inspections and repairs for property owners in Tampa, FL and the surrounding communities. If your furnace keeps throwing error codes, take it as a sign that it’s trying to tell you something.
We help homeowners fix the underlying cause, and not just clear the code. Reach out to our team for a heater error code inspection today.