Wood Heat

Too Much Charcoal Building Up in a Wood Stove

Most of us appreciate wood that makes a nice bed of coals when it burns. But sometimes you can get too much of a good thing. I once had an EPA certified wood stove with a small firebox that had this problem. Sometimes a bed of slowly smoldering charcoal would build up so much that there wasn’t much room to put enough wood in to make a hot fire.

This was especially a problem during cold weather when I was going through a lot of wood 24 hours a day. The more wood I burned, the more charcoal would build up. This was also a bigger problem in cold weather because that is when I wanted to be able to put more wood in for a hotter fire. But with all the coals in the way, I had a problem and I didn’t want to let the fire die down enough to scoop the coals out because the house would get cold if I did.

EPA certified stoves are more likely to have this problem. This is because of the higher temperatures inside the firebox. This causes the more volatile and faster burning compounds to burn off quickly leaving more of the slower burning coals.

What I learned to do is to move the coals around so they would be right next to the air inlets inside the firebox. This stove had the airwash system that blew air over the door glass to keep it clean. So I would pull the coals up front as close to the door opening and piled as high as I could without the coals spilling out. Then put some small split pieces of softwood on top of the coals.

With the air blowing down on the coals and the fast burning wood on top, the coals would flare up and burn up. At least those in the direct airstream would. As they burned away I would keep pulling more into the airstream and repeating the process until the charcoal was down to a more acceptable level.

Does Burning Softwood Cause Creosote in a Chimney

I have read a lot of articles about how you should never burn softwoods because they will cause creosote to build up in your chimney, and if you do your house will likely burn down. The idea is that the resins in softwoods cause the creosote to build up. But these are mostly rumors.

Creosote buildup is primarily caused by the chimney flue cooling the exhaust gasses enough to where they start to condense onto the walls of the flue. This is the case with both hardwoods and softwoods. If these exhaust gasses are above 250 degrees Fahrenheit, they will rise out of the chimney the way they are supposed to. When the temperature of these gasses falls below 250 degrees, they condense on the flue surface and build up.

There are a couple main causes of low flue temperature. The first and maybe the most common is the wood burning appliance operator. Burning wet wood releases water from the wood and absorbs heat from the combustion and the exhaust gasses, causing it to cool. Burning wet wood is a big cause of creosote buildup.

Restricting the oxygen supply or dampering down causes the wood to burn more slowly or even smolder. This may be good for holding a fire all night, but it creates a lot of particulates and unburned gasses without a lot of heat. The cooler and dirtier gasses will likely cool enough as it rises up the chimney to deposit creosote.

The best ways to prevent this is to burn dry wood and burn hot fires instead of smoldering fires. If you want less heat, instead of throttling the air supply, simply put in less wood and make a smaller fire. This is easier done with smaller pieces of wood.

Now back to softwoods causing creosote. Resinous softwoods are well known for burning quickly but more intense. A lot of people don’t like softwood because a lot of the heat goes up the chimney instead of radiating into the room. With more heat going up the chimney, there may actually be less creosote.

The other main cause is poor flue design. If you are burning hot fires with dry wood and still having problems with creosote, you should have an expert come inspect your system. Some poorly designed flue systems can cause the gasses to cool too fast no matter how you burn wood below.

On the flip side, there are some chimney flues that are so good that you can burn all the wet wood you want without a problem. This is partly why there are so many conflicting stories on this subject.

Even in the best cases, all wood burning flues will have some buildup and all flues should be cleaned regularly. This article is only my opinion. Contact a trained professional for real advice. If you do a search, there are a lot certified chimney cleaners who have websites with great information on keeping your flue safe and clean.

Wood Fired Water Heater

A wood fired water heater can be good for off grid applications. We have one in a remote cabin and it produces all the free hot water we want to use. It’s similar in shape and size to a small gas water heater but has a small wood firebox at the bottom.

This type of water heater can be plumbed into your home’s hot water line, just the same and just as easy as any traditional gas or electric water heater. We actually have both a propane and the wood fired water heater hooked up parallel next to each other. A valve between the two allows us to simply direct which one the water will flow through.

The only problem with the wood fired water heater is there is some inconvenience. In order to have hot water we have to plan ahead and build a fire ahead of time.

The firebox is small and the door is even smaller so it can only handle small pieces. It does draft very well and is easy to get a fire started. We mostly use small flakes and wood chips that accumulate around our wood splitters for fuel. Just a few of these is all it takes to heat the whole tank of water.

It can take up to 20 minutes to a half hour for the water to get over 120 degrees. At that point there is enough hot water for two hot showers. And I don’t mean just quick showers, there is actually enough to enjoy a good shower, plus enough left over to wash the dishes.

For a remote vacation home, the wood fired hot water heater works great. For every day use, building a fire every time you want hot water is probably too much of an inconvenience for most. But for someone who has no other choice, or for someone who just wants to heat their water with free renewable energy, a wood fired water heater like this one can be very practical.

Our water heater was bought 10 years ago or more and unfortunately the manufacturer is no longer building them, otherwise I would include their contact information. If you know of anything similar or have had any experience with wood fired water heaters that you can share please post a comment below.

I recently found a new wood fired water heater made by an Australian company. I have not tried it but it looks promising. It is a simple and clever way to use heat from your wood stove to heat your water. Check out the Axeman Fire Flue wood fired hot water heater.

Wood Fired Hot Water Heater – Axeman Fire Flue

Why Smart Consumers Buy Firewood in the Spring

For most people, thinking about firewood is the last thing on their mind in the spring. They are just finishing their burning season and in their minds, winter is a long way away. But the smartest, most experienced firewood users know that right now, before summer, is the time when they should be stocking up on firewood.

Most people wait until the last minute and buy their firewood in the fall. Some may even think they are buying their wood ahead of time by buying it in the late summer. Buy I hear a lot of stories from people who buy their winter supply of firewood late in the season and then commonly end up spending the whole winter struggling to stay warm trying to burn wood that is not dry or seasoned.

Firewood can appear to be dry on the outside and may even have cracks but may still be full of water or sap on the inside. The sap inside green wood can take a whole summer to dry depending on the drying conditions.

The best way to ensure you have fully seasoned firewood is to buy your wood before the summer and dry it yourself. When you buy your wood ahead of time you can buy it green, usually for a lower price than that of seasoned firewood. Late in the season is when everyone else is buying their wood and that is when firewood prices are more likely to increase. Early in the year demand for firewood is lower and you can usually find better prices.

What the Really Experienced Firewood Users Do

The really experienced firewood users buy their wood a year in advance. They already have their wood for next winter that they got last year. Now this spring they are stocking up for the winter after next. This way their wood has over a year to dry and they always have a year supply of wood on hand.

This may not work so well for people who do not have the space for two years supply of firewood but for those who do, they always know they will have dry wood and they are a full year ahead of price increases. This method can also be good for consumers who have a hard time paying for a full year supply all at once. Since you are buying your wood so far ahead of time you can buy a little at a time throughout the year as your budget allows.

How to Burn Firewood More Efficiently in a Wood Stove

How to Burn Firewood More Efficiently in a Wood Stove or Fireplace

Learning to burn firewood more efficiently can help you get more heat and save money by burning less wood. This also gives the benefit of cleaner air for you and your neighbors to breath, both inside and outside your home. A cleaner burning fire will produce less creosote buildup in your chimney and on the glass on your wood stove. Smoke not only causes pollution, it is a wasted energy since smoke is unburned fuel that wasn’t converted to heat.

If you don’t have a modern certified wood stove, you might want to look into one since they are usually cleaner burning and produce more heat from less wood. But with some practice and the right knowledge you can make a clean burning and more efficient fire with both older non certified and certified stoves that will produce little or no visible smoke.

Here are Six Steps to A Cleaner Burning More Efficient Fire

Burn Seasoned Dry Firewood

It is very important to burn firewood that is seasoned and dry. Burning green or wet firewood will significantly reduce the heat output of your wood stove and increase smoke an creosote buildup in your chimney. Firewood should be seasoned for at least 6 months or up to a full year in some conditions. Learn how to season firewood.

Start Your Fire Right

Start a small hot fire using small pieces of firewood and kindling. Starting a fire with small dry pieces will give you a hot cleaner burning fire more quickly. It is good to keep your wood stove door slightly open for about a minute to allow extra air flow to get the fire going quickly before latching the door. Just make sure you latch it after the fire gets going. You don’t want an unattended fire to escape and burn your house down.

Get Your Stove Hot

Get your stove hot enough that it will re-burn the smoke the way it was designed. Start with a small hot fire and load more in one at a time as they are needed. Loading up your stove with several large pieces at once can cool the fire and create an inefficient burn and even a smoldering situation.

Maintain Your Fire

In older stoves especially, don’t close off the air flow too much since this makes the fire smolder and smoke. Don’t overload any stove since this also causes it to smolder and smoke. This wastes your fuel and money, causes creosote to build up and pollutes the air.

Keep the Wood Stove Doors Closed

Once the fire is going you shouldn’t open the doors unless you are putting in more wood. Wood stoves are designed to operate with the doors closed. When the door is opened, much of the heat will go out the chimney.

Never Burn Garbage

Garbage, newspaper or junk mail should never be burned in a wood stove. In some areas it is illegal. Paper can be used for starting fires but other than that the only things that should be burned in a wood stove are firewood, fire starter and manufactured fire logs approved for burning in a wood stove.

If all these steps are working properly you should be able to go outside and see no visible smoke coming from your chimney. There should be only hot air and water vapor.