A chimney sweep’s brush vs chimney sweeping logs. Do these logs really clean the chimney? I have been cleaning chimneys for 30 years now, and I get this question asked of me several times each year. I cannot speak for the cleaning logs because I have not observed their effect over time with various degrees of creosote build-up.
To be able to answer this question, I would have to start with a clean chimney. I would have to record how much wood was burned over a given period of time and how long it took for the chimney to get to the point where a manual sweeping was required. And of course, I would need to keep a record of when the chimney cleaning logs were used. If you have a pre-existing heavy build-up of third-degree creosote, then the cleaning log is not going to handle it. You will need to call in a sweep that has experience in using specific chemicals, equipment, and procedures to remove this dangerous build-up.
Other points to consider: what your chimney sweeping log can’t see.
Your chimney cleaning log does not have a trained eye for the condition of your chimney and fireplace or wood stove. Consider this standard Condition Report that we fill out as a routine part of a chimney cleaning (Click image to enlarge:)
There are 21 points of inspection. Chimneys are not rocket science, and a close inspection with some common sense can alert you to the majority of things that can be wrong with a chimney, fireplace, or woodstove.
My best advice (if you are going to use these logs) is that you start with photographs of your chimney flue interior and the smoke chamber above the damper. Record all of the data I listed above and come to your own conclusion. The cleaning logs do not take the place of structural and mechanical inspections; these need to be done as well.
And remember, there are simply situations where cleaning logs do not take the place of chimney sweep brushes.
The safe bet is that you start with a chimney that is clean, and use the log as a preventative maintenance measure.