Chimney Spark Arrestors: Everything You Need To Know

  • A chimney spark arrestor prevents sparks and embers from falling onto your roof or onto combustible materials on the ground and potentially starting a fire
  • Generally, they’re made from double layers of metal mesh that catches the embers but also enables smoke and gases to leave the chimney
  • Most chimney caps have integrated spark arrestors- meaning they have mesh screens included
  • They are necessary- so if you aren’t sure you have one, get a chimney inspection

Fire accidents can cause unprecedented damage when they occur. Preventing or reducing the risk of fire is the best way to keep your equipment or yourself safe. Sparks, for example, from an internal combustion engine, wood stoves, or our fireplaces can result in fires and explosions during their operation.

Spark arrestors are commonly used in such settings to tame fire from accidental ignition by trapping or destroying the hot particles released by the internal engine combustion or fireplaces. Spark arrestors have been used since the early 1800s.

chFor example, locomotives used screens to keep off accidental fires from occurring.

Since the 1800s, spark arrestor technology has advanced, and today they come in different sizes and for different equipment, but their purpose remains unchanged. This article explores some of the basic principles fire arrestors use to prevent fire and how to clean them.

So, What Are Spark Arrestors?

Spark arrestors are devices designed to eliminate or reduce sparks emitted from a combustion engine before igniting, causing an accidental fire.

Spark arrestors are commonly used in welding, metal cutting, and grinding equipment where sparks are constantly generated.

The law dictates manufacturers in industries such as car and power cutting equipment to install spark arrestors to enhance the safety of their products.

How Do Spark Arrestors Work?

Spark arrestors trap carbon particles with a diameter greater than 0.023. The mechanical equipment traps or pulverizes the large carbon atoms from the internal combustion engine or the equipment generating sparks.

The arrestor traps the carbon particles which go through the screen, and the larger particles are pushed out of the exhaust system.

Through centrifugal force, the heavier carbon particles are forced into the arrestor inside walls and trapped to reduce the threat of causing fire and burning the engine. The arrestor uses either a screen or a disc during the screening process. Using more discs for the disc type arrestors is recommended to make the exhaust efficient and reduce backpressure.

What Are The Common Types of Spark Arrestors?

There are different types of spark arrestors used in different equipment. Although spark arrestors may appear different, they all have the same purposes. Here are some of the common spark arrestors you may come across:

1. Fallout Arrester

The fallout arresters are designed for large machines. They are notably long and are held in a large chamber to allow the heavy carbon articles to lose velocity and drop at the bottom of the chamber. This kind of arrestor is reliable and safe for heavy machinery and trucks.

2. Trap Arrestor

The general-purpose arrestor is perfect for those looking for a cost-effective solution to eliminating sparks before they cause a fire accident. It works in two different ways, trap and screen the carbon particles. Trapping uses centrifugal force to trap the heavier particles, while screening relies on the screen to push lighter particles out. Trap arrestors are popular in welding and cutting machines but also in industrial dust collectors to extinguish sparks and burning embers.

3. Pulverizer Arrester

The pulverizer arrester compresses the carbon particles by circulating gasses within the arrestor, just as the word suggests. The pulverizer arrestor is a superior quality flame extinguisher commonly preferred for heavy industrial machines.

What Happens When Your Spark Arrestor is Clogged?

The efficacy of the spark arrestor is compromised when it is clogged. For example, you may notice the engine is not accelerating to its optimal capacity. In vehicles, clogged arrestors may lead to a higher spit back via the carburetor and zero power under the load.

It is always recommended to have your spark arrestor checked when you suspect it is clogged. If the spark arrestor screen is blocked, consider cleaning or replacing it if overused.

How to Clean a Clogged Spark Arrestor?

Here is a simple guide to cleaning a spark arrestor to prevent accidental fires from sparks and fire embers from your equipment because of clogged spark arrestors. The example below is for a small motorcycle engine.

  1. Remove all the screws to allow you get to the muffler.
  2. Always wear safety gloves and glasses, and then take away the spark arrestor housing so you can separate it from the muffler.
  3. Once you separate the spark arrestor from the muffler, you can safely take out the spark arrestor screen.
  4. Cleaning the spark arrestor screen use a blow torch and needle-nose pliers. Make sure you do this from the outside.
  5. Put the screen somewhere clean to allow it cool to the touch before fixing it back in the exhaust pipe.
  6. For the rest of the spark arrestor, wash with clean soap water to remove any other clogged materials.
  7. Mount everything back, and your engine will work like it’s new.
  8. Precautions to Take When Cleaning Spark Arrestor
  9. Avoid using wired brushes to clean the screen. The brush scratches the screen, which can cause accelerated plugging.
  10. Wait until the screen is cooled off to further clean it if unsatisfied with the first cleaning.

Good Maintenance Practices for Spark Arrestors

Spark arrestor maintenance goes a long way toward safeguarding your equipment’s performance and reducing fire risks.

Maintain a regular inspection routine to ensure they remain in excellent condition. It is recommended you inspect your spark arrestor after 1000 hours of operation.

Always buy an approved spark arrestor or from reputable brands or sellers. This way, you are guaranteed safe and quality spark arrestors.

Sparks arrestors play a critical role in preventing accidental fires and enhancing the functionality of many power equipment and locomotive engines. Understanding how they work is a fundamental step in buying quality spark arrestors and ensuring proper maintenance practice.

While this article presents detailed information about spark arrestors, there is a ton of information purposefully left out to enhance the article’s simplicity and ease of understanding. You are always recommended to research more and iron out your insight about spark arrestors.

Eugene Duke Pic

Hi, my name’s Eugene Duke and I love sitting by my fireplace reading a book and sipping on an adult beverage. Do you have a fireplace in your house? I’ll help you figure out the best type and style of fireplace for your home.


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