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Goodman Furnace Won’t Ignite: Repair Tips

Is the temperature rapidly dropping outside and your Goodman furnace won’t ignite? This is a scenario that many homeowners dread, particularly if it happens as night begins to fall and the temperatures drop even lower. You may be tempted to double up on the blankets, but there could be a simple solution to your furnace woes.

If you need to get the heat running in your home as soon as possible, then you need to understand why your Goodman furnace won’t fire up. Here are a few of the likely culprits and how to correct them quickly.

No gas supply

One of the most common culprits of a furnace that is having a difficult time lighting is a low gas supply. This may be the case if your Goodman furnace won’t ignite, but the light is on continuously. All you need to do is locate the gas supply valve and rotate it in a counterclockwise direction to open it. It is typically located either beside or behind your furnace if you are having a difficult time finding it.

After turning the gas supply back on, your furnace should be able to ignite itself. If you smell gas, immediately turn the furnace off and contact the gas company or emergency services.

High limit switch

High-Temperature limit switch

A Goodman furnace with four blinks could be indicating that you are reaching a high limit. The limit switch is a temperature sensor attached to a mounting plate inside the furnace housing. This piece is in control of activating the blower fan to circulate air through the heat exchanger and into the house while also pulling cool air into the unit.

Heat exchangers

If you see four blinks on your furnace, it could be because the heat exchanger got too hot. The limit switch will shut the burners off when this occurs to prevent damage to the entire unit. An overheated heat exchanger can be an extremely expensive repair.

Overheating could be caused by a dirty furnace filter that is restricting air circulation through the furnace and the heat exchanger.

However, it could also be caused by a blower that is malfunctioning. If you replace the furnace filter and are still receiving four blinks on your Goodman gas furnace, you may need to contact an HVAC technician to take a closer look at your blower.

Improper ignition sequence

Has your furnace recently been turned off by a power outage or for servicing? It is possible that you need to follow the proper ignition sequence in order to power your Goodman gas furnace back up.

  1. Start by turning the power and external gas valve to the off position. Lower your thermostat as far down as it will go, open the access door, and turn the internal gas control knob off. Allow the furnace to sit for five minutes in this position, smelling closely for any trace of gas in the air.
  2. As long as you do not smell gas at the end of the five minutes, you can turn the furnace back on.
  3. Turn the internal gas knob back on and shut the access door. Reopen the external gas valve and turn on the electrical power. Readjust your thermostat to a comfortable indoor temperature.

This should effectively reset the ignition sequence and allow your furnace to reboot itself to keep you warm this winter.

Obstruction in the air intake

If your Goodman furnace won’t ignite, it could be caused by a major obstruction in the air intake system.

  1. Examine the pipes that allow for air intake to make sure they are free of all debris and other types of blockages.
  2. Clean them out if it is at all possible. Depending on the model you have, these pipes could be located near the top or the bottom of your furnace, so be sure to consult your owner’s manual.
  3. While you are examining this area, you should also check the flue pipes for possible obstructions. In order to do this, make sure that the unit is turned off and cooled down before you open the access panel doors. You should be looking at the pipes that lead to the burners and pilot light. Don’t make any adjustments to these pipes while you are in there.

More serious issues

If you attempt all of these quick and easy remedies to get your Goodman furnace to ignite and it still doesn’t start, you might have a more serious issue. The heat exchanger or the burner could be to blame for the chill in your home.

Cracked heat exchanger

Replacing these parts can be expensive, and it typically requires a great degree of technical skill. Consult an experienced heating and air professional for making these major changes to your furnace.

A furnace that doesn’t run on a cold winter night can pose a major problem for you and your family. You will want to resolve the issue as quickly as possible, so be sure to consider all of these potential sources of problems. With a little bit of effort, you may be able to get the heat flowing to your home again in no time at all.

Michael Joseph