Why does my glass go black within minutes of lighting my log burner?

If your glass goes black within minutes of lighting your log burner, it is likely due to the incomplete combustion of the wood or other factors related to the burning process. Here are some common reasons why this might happen:

1. Moisture content in the wood: Wet or unseasoned wood contains a significant amount of moisture. When you burn this wood, a lot of energy is used to evaporate the water instead of producing heat. This inefficient burning can lead to the formation of soot and creosote, which can deposit on the glass, turning it black.

2. Insufficient air supply: For efficient combustion, wood requires a sufficient supply of oxygen. If the air vents on your log burner are not fully open or if the airflow is restricted, it can lead to incomplete burning and the production of soot, which will accumulate on the glass.

3. Poor draft: A poorly designed chimney or inadequate draft can cause smoke and soot to linger in the firebox rather than being drawn up the chimney. This can result in a build-up of soot on the glass.

4. Incorrect burning techniques: If you're not using the right burning techniques, such as stacking the wood improperly or using damp wood, it can lead to incomplete combustion and a blackened glass.

5. Quality of wood: The type and quality of wood you burn can also play a role. Certain types of wood produce more creosote and soot than others.

To reduce the blackening of the glass, here are some steps you can take:

1. Use dry and seasoned wood: Ensure the wood you use has been properly dried and seasoned to reduce its moisture content. Dry wood burns more efficiently and produces less soot and creosote.

2. Ensure proper air supply: Make sure the air vents on your log burner are fully open and that there is adequate airflow to support efficient combustion.

3. Have your chimney and log burner inspected: Regularly clean and inspect your log burner and chimney to ensure they are in good working condition and that there are no blockages or issues affecting proper airflow.

4. Use the right burning techniques: Learn the proper techniques for starting and maintaining a fire in your log burner to maximize efficiency and reduce soot formation.

5. Consider using different wood: Some types of wood produce less soot and creosote than others. Hardwoods like oak, maple, or birch tend to burn cleaner than softwoods.

If you follow these guidelines and still experience excessive blackening of the glass, it might be a good idea to consult a professional to assess your log burner and chimney system for any underlying issues.