Clean glass gas fireplaces with a fireplace glass cleaner. For water spots, use an appropriate glass cleaner with mild abrasives. Soot buildup on glass is a sign of incomplete combustion. Contact a hearth professional for a fireplace tuning and cleaning.
White or cloudy buildup on glass may be the result of condensation. If the fireplace starts up when the glass is cold, water evaporates and the glass becomes hot, leaving mineral deposits that can be removed with a mild abrasive glass cleaner. Be careful when choosing a cleaning product, as harsh abrasives can permanently scratch glass.
Gas fireplaces should burn cleanly, with no traces of soot on the glass windows. Monitor soot buildup closely, and if necessary, stop using the fireplace until the root of the problem is addressed. Problems with gas pressure, burner settings and log positioning are all potential causes of poor combustion. Buildup on the glass indicates that buildup may also be accumulating on logs, the fireplace interior, and the venting on the outside of the house. This buildup may eventually require more extensive and costly cleanup. Contact a local hearth professional for cleaning, detailing and inspection.
Clean glass fireplace windows at least one to three times a year to avoid buildup. Always use an ammonia-free glass cleaner, as ammonia can permanently damage glass.