Factory-built chimneys for solid fuel-burning appliances must comply with the Type HT requirements of UL 103 and be marked "__________".

Factory-built chimneys for solid fuel-burning appliances are specifically designed to handle the high temperatures generated by such appliances. The Type HT designation indicates that these chimneys have been tested and approved to withstand the rigors of high-heat applications, ensuring safety and effective operation.

The requirement for these chimneys to comply with the Type HT standards as outlined in UL 103 is crucial, as it ensures that they can resist temperatures up to 1,100 degrees Fahrenheit without compromising their structural integrity. This is especially important in preventing dangerous situations such as chimney fires or the release of harmful gases.

Marking the chimneys as "Type HT" identifies them as compliant with these specific standards, making it clear to installers and users that they are suitable for high-temperature applications. This classification helps to ensure proper installation, maintenance, and adherence to safety regulations, thereby safeguarding the health and safety of occupants in homes using solid fuel appliances.