How do I keep my stove glass clean?
Congratulations. You’re the proud owner of a wood burning stove. But there’s a problem – how do I keep my stove glass clean?
Chances are you’ve already searched on Google for the answer and come across lots of ways to clean the glass. Damp newspaper dipped in wood ash is the simplest method. But why does it keep happening and how can you prevent it happening in the first place? You’ll be pleased to know that there is a very simple solution and you don’t have to put up with that dirty stove glass any longer.
Why does it happen?
As with the solution, the cause is just as simple – inefficient combustion. Your new stove is designed to operate efficiently and cleanly within a fairly narrow temperature range – usually between 150C to 200C. Run the stove outside of that temperature range for any length of time and the problems start.
Too hot and you risk damaging the stove, cracking the stove glass and burning out the flue liner. You’ll also end up using an incredible amount of fuel and most of the heat will just be disappearing up the chimney. Your stove will be “over fired”. The solution? Invest in a stove thermometer and experiment with the air controls to achieve the optimum burn temperature. Remember, each stove is unique and will behave differently depending on your location and even the weather so keep on experimenting with those air controls. Get to know your stove!
Run your stove below the recommended operating temperatures and then your problems really will start to mount up. Dirty stove glass will be the least of them. If your fire is not hot enough then all the volatile oils in your fuel will not be burnt off. Instead they’ll condense out onto the coolest surface in the stove – your stove glass! All that tar and soot on the stove glass is a result of inefficient combustion.
But the problem doesnt stop there. Those same annoying tar, soot and creosote deposits which are spoiling your enjoyment of your new stove will also be covering the surface of your flue liner and you will run the real risk of a chimney fire or eventually blocking the flue enough to allow poisonous fumes.
Avoiding the problems and dangers.
Banking up the stove
It’s a great feeling to wake up in the morning and discover that your stove is still burning. You filled the stove or “banked it up” just before going off to bed, left the air controls open just a crack and, in the morning, with a bit of luck, you let more air in and whoosh it’s away again. The stove glass is really dirty and you can’t see the fire but it’s still alight. Anyway if you can get the stove hot enough hopefully all those nasty deposits will burn off – or most of them. You’ve just created the perfect scenario for a chimney fire or worse. That smouldering overnight fire will have deposited highly flammable unburnt residues – tar, soot and creosote – along the length of your flue. Keep on doing that and you will have a disaster.
Burning the right fuel
You’ve just bought a load of really cheap firewood and are feeling very pleased with yourself. You’ve saved a shed load of money. You load the stove up only to discover they refuse to burn as well as you expected. Not a problem. You cram more logs in and open all the air controls to really get that fire going.
Despite your best efforts your stove still isnt giving off any heat, you’ve gone through masses of wood, the stove glass is filthy and you can’t see the fire anyway. Every time you open the stove door smoke billows into the room. Sounds familiar?
That cheap firewood is unseasoned which means it has a high moisture content – possibly up to 60%. It was cheap because most of what you bought was water and water doesnt burn!
Plan B. You buy some coal to get a hot enough fire to burn the unseasoned wood that you saved so much money on. Hang on, didn’t you read somewhere that burning coal and damp wood together produces sulphuric acid? What will sulphuric acid do to my expensive flue liner?????
Seasoned and/or home grown kiln dried hardwood logs
As with just about everything in life, you get what you pay for. Firewood is no exception. If you want to avoid all of the problems and really start to enjoy your new stove then you’re going to have to buy some decent firewood. Good seasoned firewood should have a maximum water content of 20%. Any more than this and those logs will just sit and smoulder and refuse to burn properly. Even better is kiln dried wood which should have a maximum moisture content of 15% or less. Properly kiln dried wood is easily recognised – most of the logs will have no or very little bark remaining.
Beware of imported firewood from eastern Europe. It’s sold as kiln dried at a premium price but still has a water content of 20% or more – evidenced by the bark remaining on the logs! An interesting article on the merits of importing firewood over 2000 miles to the UK can be found HERE
Good seasoned locally grown hardwood logs or home grown kiln dried hardwood logs aren’t cheap. A lot of time and effort goes into producing really good quality fuel. What you will discover is that you’ll need much less air going through your stove to reach the correct operating temperature. That means less heat forced up the chimney and more heat in the room. You won’t need to cram the stove full of logs to generate that heat so you’ll use much less fuel. Even a single properly dried log will burn well on its own. Your stove will look great, feel great and you’ll actually end up saving money.
How do I keep my stove glass clean? Well now you know!
The author is co-founder of Border Biomass Fuels Ltd and owner of Firestop Safety – fire protection consultants.