The glass can go crazed or milky when high temperature burning fuels like Anthracite, smokeless fuels, compressed man made logs etc are burned too near the glass instead at the back or centre of the firebox.
These fuels burn very hot and if used in large quantity can send the temperature of the stove itself into “overburn” resulting in the glass going milky, crazed or spider web like appearance.
The solid fuels can be burned and as long as they are away from the glass there should be no effects like mentioned above.
Stove glass is capable of withstanding very high temperature, paper lights at 253 degrees C, wood burns at around 500 degrees C, coal burns at around 600 degrees C however, anthracite or cite based fuels are the superfuels whick kicked off the industrial revolution. These superfuels burn much higher and are used in the smelting process so please, keep them to the middle or rear of the firebox and use sparingly. They produce more heat than other fuels having a higher calorific value.
If you would like more details or assistance with the installation of a Country Kiln Wood Burning Stoves please email your query to firstname.lastname@example.org (The Country Kiln team respond to all emails within 24 hours) or call 01560 483966 Monday to Friday 9am to 5pm GMT or Saturday 10am to 1pm