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Hi, I am Melissa from NorthlineExpress and today I am here to give you some helpful tips to use when cleaning Class A chimney systems. When cleaning a Class A Chimney System it is important that you have all of the right tools and supplies. You need to choose a proper fitting brush, the correct amount of rods and lengths. No one like it to realize when you are starting the job that you either have the wrong tools or you don’t have all of what you need!

Video Highlights: 0:09 Type of Brush to use 0:38 Measuring chimney length 1:15 Choosing Rods 3:03 Chimney Brush Size 3:55 Cleaning Preparations for a Wood Stove

Tip #1: What Type of Chimney Brush to Use

First, I am going to start by talking about the type of brush that should be used to clean a metal flue chimney. When cleaning a Class A chimney you want to make sure that you are using a Poly-bristled brush. You do not want to use the metal bristled brushes because even though they seem like they will do the job better they will actually do more harm than good. The metal bristles will scrape down the inner wall of the chimney flue and they will create grooves in the metal. The grooves then give creosote a place to begin to deposit in. So make sure when you pick a chimney brush that you are choosing a Poly-bristled Chimney Brush for your Class A Pipe.

Tip #2: Choose the Correct Chimney Brush Size

Having the correct size chimney brush is very important. With Class A chimney pipe it is not as complicated as having a rectangular or oval flue. More times than not you are going to need a round brush of a certain diameter when cleaning Class A chimneys. 5’’ to 8’’ diameter chimney pipe is very common with 6’’ and 8’’ being the most frequently used pipe and you would need a brush that is the same diameter. With stove or chimney pipe the measurement refers to the inside diameter of the pipe. So, if you have 8’’ chimney pipe you will need an 8’’ round brush. To double check the opening of your chimney simply measure straight across the inner edges of the opening and this will give you the brush size you need. The bristles of the brush should touch all side of the pipe to get the most out of a cleaning. If they do not touch all side then there really is no point in using that brush as it is not going to do an adequate job and the chimney will still be at risk of a fire occurring.

Tip #3: Have Plenty of Chimney Rods Accessible

When choosing your chimney rods it is good to know that you have enough! It is better to have more than what you need than not enough because once you get up on the roof to start the job. Make sure that you measure the Class A chimney run from the top all the way to the top of the stove vent. An easy way to measure the length of your chimney run is going to be by dropping a rope from the top of the chimney all the way to the stove vent. It is easier if you have someone in the room to tell you when you are at the opening. Then you can either tie a knot to mark the measurement or if you have the tape measure handy you can mark it just by pinching your fingers and measure right away.

Tip #4: Choose the Appropriate Chimney Rods

Now that you know the length of your chimney it is time to choose the rods that will connect to the brush for cleaning. There are many options to choose from when it comes to chimney rods. However there are two that are the most common materials that the rods are constructed of to consider: Fiberglass or Polypropylene. If you have a straight chimney you can use fiberglass rods. They are going to be stiffer and more durable. They do have a little bit of give to them but they are not going to be very flexible. Fiberglass Rods work well for top down cleaning or any cleaning that has less than a 45 degree bend in the run. If you are going to be cleaning from the bottom up or if you have a 45 degree or more bend in your chimney the Poly rods are going to be the better option. Choosing the connecting ends is simply personal preference or what type of connecting end does the brush have that you are using. There are two types of connecting end: threaded which can be ¼’’ or 3/8’’ NPT or there is button Lock connectors. You are able to convert if needed. There are adapters to convert the 3/8’’ NPT or 1/4’’ NPT to the Button Lock or vice versa. The important thing to remember is to make sure that whatever type of connect you choose for the brush you either have rods or an adapter to connect everything together.

Tip #5: Prep for Catching the Debris

If you have a straight chimney run you may think you can clean it allowing the creosote to fall into the fireplace and clean it out when you are finished. If you have an older stove connected to your chimney this thought may be correct. However, for this chimney there is an EPA certified wood stove on the bottom with baffles inside so we are not able to allow the creosote to fall into the firebox. So in preparation I have disconnected the stove pipe from the wood stove and placed an ash bucket underneath of the pipe to catch the debris. If you have a telescoping piece of stove pipe it will make this easier. If you do not then I would suggest that you remove each section of stove pipe, place it outdoors to be cleaned, then tape a garbage bag around the opening of the ceiling support box to catch the falling debris.