Goodman Furnace Error Code 3 Flashes – What Is The Possible Cause?

When your Goodman furnace is giving you the error code 3 flashes, it means that there’s something wrong with the flame sensor. This can be caused by several different things and it is important to know what the possible causes are when this happens so that you can take measures to remedy them. Luckily, we have outlined some helpful tips below about what the potential reasons for this error code are and how you can go about fixing it. If your furnace is flashing Code 3 and you have ruled out any potential combustion problems such as a clogged or insufficient gas supply, then there is a high chance that your flame sensor has gone bad. This article will explain what this error code indicates and where exactly within your furnace the flame sensor sits so you can troubleshoot accordingly.

What Is The Flame Sensor?

The flame sensor is one of the safety measures within a gas furnace that help to regulate its operation. It sits at the top of the burner and is used to detect the presence of a flame to make sure that your burner is working properly and safely. As soon as the sensor detects a flame, it switches your furnace to the “run” position, which enables the healing process to begin. If the flame sensor does not detect the presence of a flame within a certain amount of time after it is first turned on, it will shut the whole system down. This safety measure ensures that your gas furnace does not remain in the “run” position for too long and could potentially lead to a dangerous buildup of carbon monoxide in your home.

Code 3 Flashes With No Combustion Problem

While it is normal for your furnace to flash code 3 intermittently, it is not normal for it to do so when there is no combustion problem present. When this error code flashes while there is no combustion problem, it is usually caused by a loose connection or a loose flame sensor. This can be resolved by tightening the flame sensor connection and/or replacing the wire harness if it has become damaged and is preventing the sensor from making a proper connection.

Possible Cause #1: The Flame Sensor Is Loose

If the flame sensor is loose and not making proper contact, then the furnace cannot sense the presence of a flame at the burner and will continue to flash the error code 3. To resolve this issue, you will want to shut down the furnace and inspect the flame sensor. You will want to make sure that it is making proper contact with the burner and that the wire is not being pinched or causing the sensor to come in contact with the burner. If everything looks to be in order, you may want to consider tightening up the sensor to make sure it is not loose. If the sensor has become corroded over time due to exposure to high levels of carbon in the air, it may also be causing it to become loose. In this case, you may need to replace the sensor.

Possible Cause #2: The Wire Harness Has Come Apart

Another possibility is that the wire harness connecting the flame sensor to the furnace’s control board has come loose and is preventing the sensor from making a proper connection. In this case, you will want to shut down the furnace, inspect the harness, and re-tighten the wires if necessary. If the wires have come apart, then you will want to repair the harness using high-quality electrical tape.

Possible Cause #3: The Flame Sensor Needs To Be Calibrated

Finally, the flame sensor may need to be calibrated. Every sensor has a certain range of operation, and if it is used outside of that range consistently, it may need to be calibrated to make sure it is working properly. You will want to call a professional to come out and calibrate your flame sensor. If you have ruled out all of these possible causes and the code 3 flashes remain, you may want to consider hiring a professional to come out and look at your furnace.

Conclusion

When your furnace is giving you the error code 3 flashes, it means that there’s something wrong with the flame sensor. This can be caused by several different things and it is important to know what the possible causes are when this happens so that you can take measures to remedy them. Fortunately, this article outlines some helpful tips about the potential reasons for this error code and how you can go about fixing it. If you are experiencing issues with your furnace, make sure that you know what the error codes mean so that you can address them as soon as possible. It is also helpful to know where certain parts are located within the furnace so that you can troubleshoot appropriately. With these tips in mind, you should be able to pinpoint and resolve the issue quickly.