Yes, it is possible. An electrical fire can break out if the compressor has inadequate ventilation. When it overheats but doesn't have a proper thermal cutout, this can cause the motor to short-circuit and catch fire. This risk is exacerbated if flammable materials, like dust and fallen leaves, are clogging the unit. The compressor overheating won't start a fire by itself, but poor maintenance and installation can increase the risk once it hits its breaking point and short-circuits.

Asbestos has many beneficial properties, including fire resistance, strength, and chemical resistance. It is also an excellent insulator, which is why it was used in pipe insulation and other building materials for decades. For all its benefits, asbestos is dangerous for human health, which is why it was eventually banned from use in certain products.

A chimney liner isn’t required for an outdoor fireplace; you don’t technically need one if the masonry chimney uses the proper dimensions and is built to code. However, a chimney liner does serve as a protective coating for the flue. Adding a liner could improve performance, safety, and durability. In short, while not necessary, it wouldn’t hurt.

You should never block both the top and bottom of your chimney. Proper airflow is essential because the temperature inside the chimney will still fluctuate as your house warms and cools. Moisture can build up without ventilation, leading to dampness in your walls over time. Blocking the top prevents debris and animals from entering, but the chimney still needs air circulation to avoid condensation issues. Allowing the chimney to breathe maintains the health of your home and prevents long-term damage.