Watching your beautiful fire pit glass darken and discolor can be a startling experience. But not to worry — your “burnt” fire glass is absolutely fine. The fact is that fire glass is non-combustible, and it hasn’t been treated with any chemicals or additives that can produce a residue on the glass.
What you’re looking at, actually, is a fine coating of black soot on the surface, which happens when the gas in your fire pit or fireplace isn’t burning properly. This is most common in fire installations that use liquid propane (LP) such as a propane fire pit.
Here’s the Solution to Preventing Burnt Fire Glass
Unlike natural gas that is clean and light, LP gas is a denser, heavier fuel that requires the addition of air to the gas. Otherwise, it won’t burn cleanly and will produce a black soot and will result in your fire glass turning black. This black soot is visible as smoke rising from the flames that also leaves a black coating on your fire glass and propane fire pit. An LP gas air mixer will fix this problem by mixing additional air with the gas. This results in the most clean and efficient fuel source possible — and less sooting. Soot typically occurs when there is no LP air mixer present at all in a fire pit installation, or when it is undersized for the burner.
How to Clean Soot Off Your Fire Glass
The good news is that no matter how discolored your fireplace glass is, it’s fast, easy, and inexpensive to remove the soot. All you need is some water, regular household vinegar, a bucket and a strainer! In just a few minutes, your dirty glass will be restored to its original, glamorous luster and sparkle.
Get Your Air Mixer Professionally Installed
Propane gas is highly volatile! As with any kind of installation that involves gas, you should have your new air mixer installed by a trained professional. When looking for a trained professional, it’s a good idea to choose one with an NFI (National Fireplace Institute) certification. An NFI-certified installer has received the proper training in gas hearth appliances and passed NFI’s rigorous exam, ensuring they meet high standards for safety and proper installation.