One of the most beautiful things about a stove heater, besides the embracing heat is the view of the fire you can see on the other side of its clear window.

But a viewing window does more than just give pleasure. This window allows you to see at glance if your fuel load might need adjusting, and when it’s time to refuel. It also allows you see if the fire is not in flame, but is simply smouldering, which can cause chimney fires. Chimney fires can be caused when soot or wood tar deposits build up in the stove. The heat from the fire warms the deposits release combustible materials.

When these materials ignite the fire migrates up the chimney and expands the fire. You can tell you have a chimney fire when a roaring noise can be heard in the chimney. A mass of smoke will pour out of the chimney and then flames will be seen coming out of the chimney. If you hear the roar or see the flames call an emergency line right away. But what happens when that window gets fogged, and then clouded, and then its translucence is stolen by collected ashes and smoke stains? That’s where an Air Wash System comes in.


If you have an air wash system in your stove you’ll know, because you almost always will be enjoying the glow from the window. If you don’t have it designed into your stove you’ll know it too. Cleaning that window is no fun, if you can clean it at all. Most stoves built since the 1980s that have ceramic glass panels in their doors have an air-wash system designed into them. Through a narrow slot on the top inside edge of the glass, the air-wash system supplies most of the air to the fire.

It is designed to make the combustion air sweep down between the glass and the fire so that soot cannot stick to the glass. Airwash systems help to keep the glass on a stove clean. It does this by a drawing air (washing) over the window, this helps to keep the smoke and gasses away from the glass and keeps them in the stove burn chamber. Stoves without airwash tend to get tar deposited on the glass, causing the glass to darken and become black over time. Good air-wash systems a great at this task and keep the glass clear for weeks of 24 hour a day usage.

Air-wash systems, like everything, have their limits, and every so often a white or a grey haze can form on the glass. The haze is easily removed with a damp paper towel when the stove is cool. Light brown stains can also form at the corners of the glass, but can be removed by a good glass cleaner. If dark stains appear and are hard to remove the stove may have a poor air-wash system, or possibly wet fuel. Smouldering fires can also cause hard to clean dirty glass.

Dirty glass can be cleaned with a commercial cleaner or by grabbing a handful of newspaper, misting it with water, and then rubbing the newspaper in the fireplace ashes. The grit will buff away the majority of the film. This method works best when the wood stove is warm. Be sure to wear gloves to protect your skin from the heat. Finish the job by spraying a mixture water and vinegar on the window and wiping. If the stain is really hard to remove try water and baking soda. Follow up both cleanings with a dish detergent wipe for a streak free shine.