7 Reasons Why Goodman Furnace Won’t Stay Lit [Easy Solution]

Your Goodman furnace won’t stay lit? We will show you how you can fix it. 

If your furnace won’t stay running, there are a few reasons behind this. Fortunately, there are easy ways of dealing with these situations as well. And in this article, we will talk about it all.

Here, you will know 7 reasons why the Goodman furnace won’t stay lit and what can be done to fix it. Goodman furnace troubleshooting manual approves of the instructions we discussed in this article. This means you are sure to get your furnace fixed without spending a single buck.

So, let’s get started.

7 Reasons Why Goodman Furnace Won’t Stay Lit [Easy Solution]

Your Goodman furnace may not work properly due to the 7 most common reasons. These causes are a dirty flame sensor, insufficient airflow in the furnace system, dirty pressure switch tube, broken thermostat, faulty circuit board, faulty thermocouple, and bad blower motor performance. 

These are usually the case when your Goodman furnace lights up and goes out. If your furnace has any of these problems, you have nothing to worry about. Here’s what you can do about these issues.

Reason 1: Clogged Pressure Switch Tube

Near the draft inducer fan, you will find a circular control switch. It’s the pressure switch of the furnace. 

There is usually a tube attached to this switch that controls the flow of pressure in the furnace. With time, dirt and debris can clog this pressure switch tube. When this happens, the imbalance of pressure will prevent your Goodman furnace from working properly. 

Solution: Cleaning the furnace pressure switch tube will solve this issue. To do this, you have to,

  • Turn off the furnace
  • Pull off the pressure switch tube
  • Clean the debris at the front of the tube
  • Apply canned air in the tube to clear deeper clogs
  • Make sure the tube is totally dry before putting it back in its place

Reason 2: Insufficient Air Flow

Overheating causes the furnace to shut off. This might be the case with your Goodman appliance. Warm air constantly escapes the furnace system. However, if the airflow is somehow hampered, the warm air accumulates inside the furnace system.

As a result, the furnace overheats pretty quickly. And when this happens, the furnace doesn’t stay lit anymore. 

Solution: Ensuring proper airflow in the furnace will get the system back to normal. You can easily do that just by changing the air filter regularly. Here’s how,

  • Turn the furnace system off
  • Remove the furnace service panel
  • Pull out the air filter located there
  • Clean the slot of the air filter
  • Slide in the new air filter
  • Turn on the furnace

Reason 3: Dirty Flame Sensor

The flame sensor signals the furnace system to light up or turn off. Your Goodman furnace will not stay lit if the sensor is dirty. A dirty flame sensor sends the wrong message to the system, resulting in a shut-off of the furnace flame. 

Solution: Cleaning the flame sensor will take it back to working properly. Follow these steps,

  • Turn the furnace off
  • Remove the cover of the furnace to reach the flame sensor
  • Unscrew the flame sensor and pull it out
  • Use sandpaper to rub the metal rod of the flame sensor gently
  • Use a cloth to rub the position of the flame sensor
  • Put the flame sensor back in its place
  • Rewire the flame sensor before turning the furnace on

Reason 4: Faulty Circuit Board

The Circuit board basically controls all the functions of your Goodman furnace. If this circuit board fails for some reason, it will stop sending signals to the furnace. As a result, your furnace will not light up.

Solution: Fixing the furnace circuit board is not worth it. This is why we recommend replacing it as a whole. Here’s how,

  • Turn off the furnace
  • Take a picture of the circuit board wiring. You will need it later
  • Remove all the wiring of the circuit board
  • Remove the circuit board screws before removing the board itself
  • Place a new circuit board and screw it there properly
  • Rewire the circuit board according to the picture you took earlier
  • Start the furnace system and see if it’s working well

Call a professional if the furnace doesn’t work at this point.

Reason 5: Faulty Thermostat

Just like the flame sensor, the furnace thermostat works as a mode of communication. It informs the system about the furnace’s condition. If the thermostat is broken, it will signal that the furnace has reached the desired temperature.

As a result, the furnace will stop generating heat. It will not stay lit anymore.

Solution: Changing the furnace thermostat is the best solution in this kind of situation. Here’s how to do it easily:

  • Turn off the power supply to the furnace system
  • Reach the thermostat system
  • Remove all the wires attached to it. Don’t forget to take a picture of the wiring
  • Remove the thermostat
  • Clean the area
  • Mount the base for the new thermostat
  • Install the new thermostat on this base
  • Install the wiring in accordance with the picture you took
  • Turn on the power supply

You can also watch the video to replace the thermocouple.

Reason 6: Defective Thermocouple

The thermocouple is another sensor device. It senses the temperature of the furnace system and controls the gas valve accordingly. 

A broken or defective thermocouple will signal the gas valve to close as soon as you turn the furnace on. As a consequence, there will be no gas supply in the furnace. In other words, your Goodman furnace will not stay lit.

Solution: Simply replace the thermocouple to get your furnace back to working. Here’s how it’s done:

  • Open up the furnace access cover
  • Locate the thermocouple near the gas control valve
  • Take an open-end wrench to unscrew the nuts holding the thermocouple in its place
  • Disconnect the gas connection of the thermocouple
  • Gently pull the thermocouple out of its place and mark the location
  • Screw a new thermocouple in the marked spot
  • Reinstall the gas valve connections to the thermocouple
  • Power on the furnace 

Sometimes, you may find after replacing the thermocouple, your furnace pilot won’t light still. Then you can learn why your furnace pilot light won’t stay lit after replacing the thermocouple & solutions.

Reason 7: Malfunctioning Blower Motor

A Blower motor keeps your furnace system cool so that it can work properly. However, this blower motor may malfunction due to many reasons. When it fails to complete its task, the furnace system overheats. And you already know that overheating leads to shut down of the furnace.

Solution: There are a few things you should ensure. Here they are,

  • Make sure that the blower motor wiring is not damaged and is perfectly secured
  • See if the blower motor is dirty. If it is, use a can of compressed air to clean it
  • Install a new blower motor in case the motor is completely broken

And these are all. Following these instructions should get your furnace back to working. However, if you have tried all these methods and your furnace is still not lighting up, call an expert. The problem is probably not what you think.

FAQ:

Why does the flame on my furnace keep going out?

A possible reason why your furnace keeps going out is overheating. If the heat exchanger gets too hot, the limit switch will turn your furnace off.

What are the symptoms of a bad thermocouple?

The most common signs of a bad thermocouple are cracks, contamination in the tube, pinhole, discoloration, absence of insulation.

Where is the reset button on a goodman furnace?

The Goodman furnace reset button is located in the middle of the rollout limit switch component. You have to hold it down for 2 seconds and then release it.

What does it mean when your furnace won’t stay on?

If your furnace doesn’t stay on, it can mean that your pilot light is faulty.

How much does it cost to replace a thermocouple on a furnace?

It costs around $150 to $300 to replace a furnace thermocouple.

How do I know if my thermocouple is bad on my furnace?

The most common sign of a bad thermocouple is that the flame will come and go out within 30 seconds.

Final Words: 

A furnace must stay lit if you want to enjoy its benefits. But even with proper maintenance, the device may have problems. However, knowing the proper way of dealing with the issues will save your appliance and your money. So if your Goodman furnace won’t stay lit, just follow what we have discussed in this article. This will take care of everything. 

Leave a comment below if you have any questions.

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