If you’ve just obtained a fresh batch of unseasoned green wood, or if the seasoned firewood in your stock has gotten wet, you need to dry them before they can be burned. A lot of people resort to using a fan, blowing air at full force towards the damp wood, hoping this will speed up the drying process.
A fan can help dry firewood if you’re in a dry, non-humid environment. If the air around you is cold and damp, then a fan is pretty much useless. But if you’re in an environment with relatively low humidity and where the air is warmer, then a fan can help you dry your firewood.
In this article, we will be exploring this subject in great detail. We will particularly focus on when and how you can use a fan to dry your damp firewood. We’ll also share some extra tips on how you can keep your firewood dry.
Using a fan to dry firewood.
If you’ve decided to use a fan to help you dry your wet firewood, good for you. You really can’t go wrong with this process, but there’s a chance it won’t do any good either. It all depends on the relative humidity of the air.
The relative humidity of air is a ratio of the amount of water vapor in the air at the moment to the amount of water vapor needed for saturation at that temperature. To put it more plainly, it helps indicate how wet or dry the air is at any given time and place.
So if you’re using a fan to dry up wet firewood, you should be mindful of the relative humidity of the air at the place. If the air is dry enough, a fan can greatly reduce the amount of time needed to dry up your wet firewood. The drying process will be a lot faster than just leaving it out in the open for the sun and the wind to do their work.
So, go ahead and use a fan during the dry seasons. A fan can dry the wood down to appropriate moisture levels in a matter of weeks. This is a vast improvement over the 6-9 months that the wood takes to dry from the sun and the wind.
But it’s practically pointless to use a fan during the wet seasons. The high humidity means that you will just be sending more moisture in the direction of the wood. There is an alternative, however; one that requires you to take the process indoors: using a dehumidifier.
Should you use a dehumidifier to help dry firewood?
Now the important question to consider here is whether you should use a dehumidifier to help you dry your firewood.
If you’re using firewood at a place where you have access to a dehumidifier, then there’s a good chance you have other alternative sources for generating heat. So, would it be economical to first use a dehumidifier to dry up the air, then use a fan to dry up your wet firewood and then finally burn the dried up firewood to generate heat?
To put it in simpler terms, the eventual cost of drying up your firewood depends on this simple equation: Dehumidifier electricity consumption + Fan electricity consumption
As you can imagine, this process will consume a lot of electricity. If you were drying some sort of construction wood, this could possibly be deemed as economical. But if all you’re looking to do is dry your wet firewood, then this would probably be a poor economical choice, and you would be better off using an electric heater.
Of course, if you might be someone who simply prefers fire over an electric heater. If that’s the case, your best bet would be to choose an appropriate place for the process. Any place that has air circulating in it is bound to mix up with the air outside.
However, the air in your basement tends to be higher in relative humidity than someplace on the first or second floor. This is because wet air tends to be heavier than dry air and hence will settle down.
Alternatively, you could invest in/build a dehumidifier dry kiln, but your best bet would still be to make the most of the seasonal changes, managing and storing your firewood in an appropriate manner.
How to dry firewood naturally.
Using a fan to dry wet firewood should always be your last choice. The best option is to naturally dry up the firewood during the drier seasons and then storing them in a way that prevents them from getting damp.
The first thing to consider is that you need to cut the wood up during spring or summer if you want them to be ready for use by the following winter, giving it a good 6-9 months to dry. Cut the wood up in big chunks in the beginning as more surface area means quicker drying.
Once cut up, avoid storing the wood indoors as the sunlight and the wind movement outside will help them dry up the quickest. Also, cover the wood with plastic every time it’s about to rain.
Another way you can speed up the process of drying is to tie some wood into a bundle and hang them from the branch of a tree or something else that is at height. With the bundle suspended in air, more air passed through and around it, helping speed up the drying process.
Of course, if you’re a little behind schedule, a fan could help you get up to “speed.” As we’ve discussed in the earlier sections, using a fan to dry up your firewood can prove uneconomical, but it can get the job done a lot quicker.
Why you shouldn’t try to burn damp firewood.
When freshly cut, most wood has around 50% of moisture content in them. This gives them a dark brown color with a greenish tinge (hence the name green wood) and makes them heavier. You need to take the amount of moisture down to at least 20% before it makes good firewood. Burning it while it is damp produces a lot of heat as most of the energy is wasted in fighting with the moisture.
Not only is burning damp firewood inefficient, but it can also actually be pretty dangerous. Burning firewood with a moisture level of over 30% will result in heavier smoke and residual tar in the walls of your chimney or flue. This tar can eventually accumulate and result in a fire.
The moisture content in firewood should be dried down to at least 20% for it to burn well and efficiently. While typically it takes around 6-9 months for wood to dry down to this level naturally, using a fan can greatly increase your speed of drying.
While fan drying can be a cheap and fast way to dry up your wet firewood in dry places, it won’t work in places where the relative humidity of the air is high. You could use a dehumidifier, but the overall cost will not be economically viable. If and when possible, you should always opt for natural methods.