Fireplace inserts have several potential disadvantages. The cost of the insert and its installation can be a significant investment, as the process can be complicated and expensive, particularly if modifications to the existing fireplace are necessary. Aesthetically, some people find that inserts lack the traditional look and authentic ambiance of an open, crackling fire. There are also ongoing costs for maintenance, cleaning, and fuel. Fuel type can be a limitation; for example, an insert may be unusable if you don't have access to its specific fuel source. Maintenance and repairs can also require specialized services, especially for gas or electric models. Finally, while an insert is more efficient than an open fireplace, it may not heat a home as evenly as a central HVAC system.

Yes, if your gas fireplace has a flue, you typically need to open it when using the fireplace. Although gas fireplaces don’t produce the type of smoke and soot that wood-burning ones do, they still release combustion gasses like carbon monoxide. Opening the flue ensures these gasses safely exit your home through the chimney. Not all gas fireplaces need a chimney, however. Always check the manufacturer’s instructions for your specific gas fireplace model, as some newer models may have different ventilation requirements.

A fireplace that doesn’t require a chimney is simply called a chimneyless fireplace. Don’t confuse these with ventless fireplaces, however. There are some fireplaces that require ventilation via a system of pipes, not a chimney. More specifically, the fireplace in question will likely be called by its name, such as electric, ethanol, or balanced flue.

When your wood stove catalyst goes bad, it can cause your stove to produce less heat or run slower than normal. You might also notice thick black smoke coming out of your chimney. If you notice any of these signs, contact a professional who installs wood-burning stoves and repairs them for an inspection and fix.