Trane Furnace Red Light Flashing 2 Times [Solved]

Trane AC blinking red light twice indicates your furnace lockout. To be more precise, Trane furnace red light flashing 2 times means that your furnace has been locked out. This is one of the most common error codes for Trance XB, XR95, XR90, and XR80 furnace models.

Though this means your furnace will not work anymore, you have nothing to worry about. We are here to help you deal with it in the simplest way. 

In this article, you will get to know 5 steps to fix if the red light on your Trane furnace flashes 2 times. If you follow the whole article, you will have a perfectly working Trane furnace within an hour. So let’s get started.

Trane Furnace Red Light Flashing 2 Times Error Code [5 Steps To Fix]

Already you know, the Trane furnace red light flashing 2 times means external lockout. And now it’s time to learn how to fix this error code in your Trane furnace. If your Trane furnace red light flashes 2 times, then you have to reset the furnace.

Here’s how to do it.

Step 1: Turn Off The Furnace

As a part of the preparation, you will start by turning off the furnace system. Just use the power switch to shut the furnace off. Don’t forget to turn off the pilot light as well.

Step 2: Locate The Reset Button & The Reset Switch

Now you have to find the reset button of your Trane furnace. It’s a bright red button, usually located near the power button. In some models, the power button itself is the reset button.

However, the reset “switch” is inside the blower housing. Make sure that the reset switch is easily accessible.

Step 3: Pressing The Buttons

Firstly, shut off the reset button by giving it a push. This will stop all kinds of power supply in the furnace. After this, you have to wait till the furnace cools down.

Now you have to press the reset “switch.”

Step 4: Keep The Switch Pressed

You have to hold the switch button down for 30 seconds. Don’t put too much pressure on the button, and don’t release it early.

See if the furnace is making any noise. If it does, don’t push the switch again. Wait for a while till the noise dies out.

Step 5: Examine The Furnace

By now, your furnace is completely reset like brand new. Reconnect the power supply to the furnace and see if it’s working properly. Call an expert if the furnace isn’t turning on. The problem is probably somewhere else.

However, if your Trane furnace reset button doesn’t work or if your furnace doesn’t have a reset button, then here’s what you can do,

  • Cut off the power of your furnace
  • Turn off the furnace breaker
  • Change the air filter
  • Turn on the furnace breaker
  • Turn on the power supply

Follow all these steps accordingly and see if they work. If you properly take these actions, your furnace will reboot doesn’t matter if it has a ‘reset’ button or not. You can get more clear idea by watching the video.

5 Suggestions To Prevent Trane Furnace Red Light Flashing 2 Times

Though our solution helps you to deal with Trane furnace red light flashing twice effectively, the situation is never good. Such problems directly affect the longevity of the furnace.

The best way to prevent these issues and keep your furnace healthy is to do some maintenance. Here are the 5 things you can do in your Trane furnace to avoid twice red light flashing error codes. 

1. Check For Miswiring

The wrong positioning of wires is one of the major reasons behind external furnace lockout. So after each maintenance session, you have to make sure that the wiring is placed perfectly. Consult the manual to see if the wires are accurately placed.

2. Clean Clogged Pilot Tube

Clogged pilot tubes usually prevent the pilot light from working. This can affect the overall function of the furnace. Keeping the pilot tube clean will solve the issue. Here’s how it’s done:

  • Disconnect gas and electricity supply
  • Remove the cover plate
  • Find the pilot tube connected to the automatic gas valve
  • Disconnect the bracket to hold the gas supply
  • Use a screw to pull out the pilot tube
  • Clean the pilot tube with a wire brush
  • Use a thin wire to clean the clogged pilot tube
  • Put all the elements back in their place

Doing this at least once a year will reduce the chance of furnace lockout.

3. Ensure Proper Humidity In The Unit

Humidity in the furnace helps it to work properly. You can ensure such humidity by installing a humidifier in the furnace. Though it’s better if you leave this task in the hands of professionals, an amateur can do it as well. Here’s how to do it:

  • Locate the position to place the furnace humidifier
  • Make a space to set the humidifier
  • Install the humidistat in a near electrical outlet
  • Connect the humidifier to the humidistat
  • Connect the humidifier to the furnace

This setup will drastically improve your furnace performance as well.

4. Ensure A Good Flame Sensor

Your furnace is very likely to go into lockout mode if the flame sensor is faulty. The flame sensor signals your furnace about the function of the overall system. If the flame sensor sends the wrong message, your furnace will go into a lockout system.

Check the flame sensor regularly. Clean the flame sensor if you see that it’s dirty. You may even need to change it if you find cracks or any such defect on it.

5. Change or Clean The Air Filter

The air filter processes air in the furnace. A dirty or old air filter can push your furnace system into lockout. Cleaning the filter or changing it will keep your furnace safe from such problems.

You can clean the air filter easily. Just take it out of its place, rinse it with clean water, and let it dry before sliding it back into its place. And if you want to replace the air filter, then just take the old air filter out, and put a new one in its place instead.

Practicing these things regularly will not only prevent furnace lockout but other issues as well.

Give our solution a try before spending hundreds of bucks after a technician. You can easily do the work of a professional if you just follow the instructions discussed here. It will save you extra money and keep your Trane furnace in its best condition.


What does flashing red light on Trane furnace mean?

The flashing of red light on the Trane furnace means that the furnace unit shut off because of some trouble.

Why is my Trane XB furnace blinking red light 3 times?

Red light blinking 3 times indicate to draft pressure error in the Trane XB furnace.

What is Error 126 on the Trane thermostat?

Error code 126 on the Trane thermostat indicates a low-temperature lockout.

Why is the green light blinking on my furnace?

The blinking green light on the furnace means that your furnace is perfectly working.

What would cause a furnace to not kick on?

A faulty thermostat may be the reason why your furnace won’t kick on.

Why is my furnace light blinking 4 times?

The furnace light blinking 4 times means that the 24 V fuse is open.

Final Verdict:

Trane furnace red light flashing 2 times is indeed a serious issue. But it should not bother you anymore because this article is all about how you can perfectly deal with this situation. So follow our suggestions and use a fault-free furnace for years to come. 

If you have any questions then let us know in the comment section below.

About William

William is the founder of He has real life practical skills in fixing smoker & heating appliance issues. He loves to share his knowledge & helps others in fixing their appliances & saving their money. William firmly believes that anyone can repair his or her unit with the correct guidance & knowledge. See more at about us.

5 thoughts on “Trane Furnace Red Light Flashing 2 Times [Solved]”

  1. So ours is flashing 2 times, but only when the cover is on the burner housing. It tried 3 times, but always snubs itself out… so having to run the furnace with the doors off the burner housing.

    • Hi Rob

      Constant flashing means your furnace is working normally. So, there is nothing to be worried about continues flashing. On the other hand, when the red light blinks, it indicates that there is a problem and your system is locked out of its normal function currently.

      Have a great time.


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