How Hot Does a Flue Get?

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  • A chimney flue can reach temperatures as high as 482 degrees Fahrenheit
  • Chimneys are designed to remove dangerous gas from the home but if they are not reaching the correct temperatures this can be dangerous.
  • The material that is making up the flue must be able to withstand these high temperatures.

People heat their homes with a fireplace because it is effective at providing heat. The chimney flue is there to help remove waste and toxic gases from the home.

This flue can reach temperatures of 482 degrees.

If a person has a double-wall chimney flue it can reach temperatures as hot as 2,000 degrees. The temperature can only be this hot for a short time because any issues may begin.

How hot?

If there is a single wall type the surface temperature will have a reading but things will get to be very hot.

If there is a double-wall chimney pipe a probe thermometer will need to be used to get an accurate reading.

The surface temperature will always be a little cooler than the flue temperature but things still get hot.

The temperature will be able to reach over 900 degrees Fahrenheit and this is okay if it stays at this temperature for a little while. If the temperature goes above 900 degrees Fahrenheit and stays that way for some time this may be a warning sign of a possible chimney fire.

This includes the temperature inside of the pipes. While they have been designed to handle the heat, temperatures above this range are not good.

When looking at these temperatures a good range for the single wall pipes is anywhere from 250 to 400 degrees F. If a person has a double pipe then the temperatures can range a little higher. They can range from 300 degrees Fahrenheit to 800 degrees Fahrenheit.

When looking at the thermometer reading it should be higher during the first 30 minutes that the heating device is being used. After this time it should be brought to a lower temperature. At this time the temperature should be a little lower allowing this to reach an average. This will not be too hot and it will not cause damage.

Why Temperature is Important

To make sure the system is working properly a person needs to know that it is up to temperature and if they should add more fuel to this.

No one can test the air that is inside the chimney or the flue. It is also important to know what is happening on the outside of the pipes and their temperature.

This will help a person know if their pipe is working properly or if there is some type of issue. If the pipes get too hot and build up tar then it may be able to explode and cause more issues.

Too Much Heat

If the flue or the pipes get to be too hot this can lead to a problem. If they reach a temperature high above normal or reach a high temperature for a prolonged part of the time this can be a warning sign that there is going to be a fire.

If the flue gets to be too hot this is where issues can begin. It is even possible that a fire can start. Some fires are the result of a flue exploding.

If the flue is not burning at the correct temperature then creosote can build up. If the flue is less than 250 degrees F then the creosote can build up and gather.

Over time this will be a fire hazard and will be one of the most dangerous things that can happen. It will be able to begin a fire at any time.

Buildup of Creosote

When the wood is brought gases, vapors, and other chemicals are being released. Check out creosote logs if you’ve got built up creosote.

The smoke from the fire goes up the flue and out of the home. If the temperature of the flue is above 250 degrees the smoke will be able to rise and get out of the home. If the temperature is low then creosote will build up and over time it will resemble glass in texture.

As it hardens it will need to be removed or if it builds up there may be a fire. Creosote will turn into tar making it a hazard and a fire danger to the home.

Warming Up

To get the flue up to temperature there are some ways to warm it. If not there can be a huge problem.

There are some easy ways to get the thing to do to get the chimney hot is to take newspaper and burn it in this. Allow the smoke the chance to wise. This will allow the flue to warm up.

This is important to do if the temperatures were cold. Allow the newspaper to burn until the smoke comes from the chimney and then wood can be added. This should be done often so that the fireplace is warm and there is no buildup- learn how to open up your flue.

Determining the Temperature

It is important to have an accurate reading when it comes to the flue. If the temperature is too high heat is being wasted. The temperature needs to be in the right range. A probe reading will be around two times higher than a surface reading.

A double wall flue should have a magnetic thermometer. This will allow for a more accurate reading and to determine if things are working as they should.d

If the flue gets to be too hot the metal that makes it up may face damage. While they are designed to withstand heat there can still be an issue if the heat is too much. If the metal is damaged then it may become weak. If it is weak and deformed then this may be an issue.

These are the average temperatures of the chimney flue and the importance of knowing these temperatures. If something happens out of this normal range it can lead to a fire. A person should also be aware of these temperatures so they do not touch the flue or go anywhere near it when it was hot.

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