Goodman Furnace Red Light Blinking: Causes & Fixes

A blinking red light on a Goodman furnace can indicate a problem with the unit.  In this guide, we will discuss the possible causes and fixes for a blinking red light on a Goodman furnace.

Goodman Furnace Red Light Blinking: Likely Causes

Limit Switch Error: The limit switch is a safety device that monitors the temperature of the furnace. If the limit switch is triggered, it will cause the red light to blink. This can be caused by a blocked air filter, a faulty thermostat, or a problem with the furnace itself.

Pressure Switch Error: The pressure switch is another safety device that monitors the pressure of the combustion chamber. If the pressure switch is not working properly, it will cause the red light to blink. This can be caused by a blocked vent, a clogged air filter, or a problem with the furnace itself.

Ignition Control Error: The function of the ignition control is to light the burners in the furnace. If there is a problem with the ignition control, it will cause the red light to blink. This can be caused by a faulty thermocouple, a clogged air filter, or a problem with the furnace itself.

Blower Motor Error: The blower motor circulates air through the furnace. If there is a problem with the blower motor, it can cause the red light to blink. This can be caused by a faulty blower motor, a problem with the wiring, or a problem with the control board.

Flame Sensor Error: The flame sensor is a safety device that detects the presence of a flame in the combustion chamber. If the flame sensor is not working properly, it can cause the red light to blink. This can be caused by a dirty flame sensor, a problem with the ignition control, or a problem with the control board.

Goodman Furnace Red Light Blinking: DIY Fixes

1. How to Fix Limit Switch Error

Step 1: Check the air filter

• The first step in troubleshooting a limit switch error is to check the air filter. A dirty air filter can restrict airflow to the furnace, causing the limit switch to trigger.

Step 2: Replace the air filter

• If the air filter is dirty, it should be replaced with a new one. Make sure to use the correct size and type of filter for your furnace.

Step 3: Check the thermostat

• If you can still notice the problem after replacing the air filter, the thermostat may be faulty and need to be replaced.

Step 4: Contact a professional

• If the problem still persists after replacing the air filter and checking the thermostat, it’s best to contact a professional.

2. How to Fix Pressure Switch Error

Step 1: Check the vent

• Start by checking the vent. A blocked vent can cause a build-up of pressure in the combustion chamber, triggering the pressure switch.

Step 2: Clean the vent

• If the vent is blocked, it should be cleaned. Make sure to use caution and proper tools when cleaning the vent.

Step 3: Check and replace the air filter

• If cleaning the vent doesn’t solve the problem, the air filter should be checked and replaced if necessary. A clogged air filter can also restrict airflow, causing the pressure switch to trigger.

Step 4: Contact a professional

• Still having issues after cleaning the vent and checking the air filter? Get a professional to have it checked out.

3. How to Fix Ignition Control Error

Step 1: Check the thermocouple

• First, you need to check the thermocouple. The thermocouple is a safety device that detects the presence of a flame and sends a signal to the ignition control to keep the burners lit. A faulty thermocouple can prevent the burners from lighting, causing the red light to blink.

Step 2: Replace the thermocouple

• If the thermocouple is faulty, it should be replaced with a new one. Make sure to use the correct type of thermocouple for your furnace.

Step 3: Check and replace the air filter

• If the problem persists after replacing the thermocouple, the air filter should be checked and replaced if necessary. A clogged air filter can also restrict airflow, causing the ignition control to malfunction.

Step 4: Contact a professional

• If none of these fixes gets the problem solved, it’s best to contact a professional.

4. How to Fix Blower Motor Error

Step 1: Check the blower motor

• Start by checking the blower motor for any obvious signs of damage or wear.

Step 2: Check the wiring

• If the blower motor appears to be in good condition, check the wiring for any loose connections or damaged wires.

Step 3: Check the control board

• If the problem persists after checking the blower motor and wiring, the control board may be faulty, so you will have to shop for a replacement.

Step 4: Contact a professional

• If the problem is not resolved after checking the blower motor, wiring, and control board, reach out to a professional.

5. How to Fix Flame Sensor Error

Step 1: Check the flame sensor

• First, check the flame sensor for any signs of dirt or buildup.

Step 2: Clean the flame sensor

• If the flame sensor is dirty, it should be cleaned with a wire brush or fine sandpaper.

Step 3: Check the ignition control and control board

• After cleaning the flame sensor, check if the problem is still there. If it is, then the ignition control and control board should be checked for any obvious signs of damage or wear.

Step 4: Contact a professional

• If cleaning the flame sensor, checking the ignition control, and the control board doesn’t solve the issue, get a professional to take a look at it.

It’s important to keep in mind that there can be multiple causes for a blinking red light on a Goodman furnace and it’s best to check and eliminate the simplest possible cause before moving on to more complex ones. As always, if you are unsure about how to fix the problem or don’t feel comfortable troubleshooting, it’s best to contact a professional to look and it and get it fixed.