Does a stoves air-wash system really keep the glass clean?

Most stoves built since the mid-1980s with ceramic glass panels in their doors also include an air-wash system. This system supplies most of the primary air to the fire through a narrow slot along the top inside edge of the glass. The air is designed to sweep down between the glass and the fire, preventing soot from sticking to the glass.

Good air-wash systems are remarkably effective at keeping the glass clear. When combined with seasoned fuel and proper operating techniques, they can keep the glass door clear for weeks of continuous operation. Over time, a white or gray haze may form on the glass, but this can be easily removed with a damp paper towel when the stove is cool.

Light brown stains often form at the lower corners of the glass and can be removed using a special wood stove glass cleaner. Dark stains, however, are more challenging to remove and may indicate that the air-wash system is insufficient, the fuel is wet, or the stove is being turned down too much. Smoldering fires and damp fuel are the most common causes of dirty glass. Burning very hot for a couple of load cycles can make dark stains easier to clean. Avoid using abrasives on the glass, as they can cause damage.

Some people suggest using a razor blade to remove black stains from ceramic glass, but this can scratch the material, which is softer than regular window glass. For more detailed cleaning tips, check out our section on How to Clean Wood Stove Glass.

Maintaining Wood Stove Glass

Regular maintenance is essential for keeping wood stove glass clean and functional. Modern wood heaters use clear ceramic glass, which is more durable and heat-resistant than the tempered glass found in older fireplaces. This ceramic glass, commonly called "stove glass," is designed to withstand the high heat generated by wood burners. However, it can still crack if the fasteners are over-tightened or if it’s struck hard by a poker or piece of wood.

If your glass breaks, you can purchase replacement glass here.

How to Remove Creosote from Glass

To prevent air leaks, the glass must be sealed tightly to the door. This is typically achieved with a flat woven gasket, often with adhesive on one side. Follow these steps to install a new gasket:

1. Clean the glass before attaching the gasket.
2. Remove the paper backing from the gasket and lay it sticky side up on a flat surface.
3. Center the edge of the glass on the gasket and press it into the adhesive.
4. Rotate the glass and press each edge into the gasket until the entire perimeter is covered.
5. Cut the gasket to the correct length and wrap the edges around the glass.

Glass gaskets usually last longer than door seals but will still need replacement over time. If you notice brown streaks on the glass coming from the door frame, it’s time to replace the gasket.

Tips for Replacement Glass

Wood stove glass is expensive but should rarely need replacement. Some stove models may cause etching of the glass over time, even with normal use. If this happens, you may choose to replace the glass to restore a clear view of the fire.

When tightening glass fasteners during replacement, ensure they are only lightly secured. This allows room for the glass to expand when heated. If the glass cracks, you may use the stove temporarily while sourcing a replacement.

Replacement glass can be cut to size by a specialty wood heating store or purchased directly from the stove manufacturer. Some EPA-certified stoves require specially coated glass. Consult your manual to ensure proper installation and to confirm that the coated side faces out.