Fireplaces, Heating Stoves, Flues and Chimneys - What is the real scoop on pine?

We have an abundance of pine here in Nor Cal, it's often available split and seasoned for free from local tree services.

I keep reading various opinions on whether to burn it. Some say never, some say a little, some way no big deal. I don't burn it exclusivley, it is usually mixed in with oak and acacia.

Does is really matter, as long as you properly maintain your fireplace?.

I'm by no means an expert on firewood but I have a wood stove in my house and another in my shop. My shop isn't insulated and I tend to burn a hot fire out there. The stove in the house usually has a slow burn.

The house stove only burns hardwood. The flue needs cleaning about once a month if used regular.

The shop stove burns mostly pine but also an assortment of wood scraps and any firewood I deem unfit [rotten,etc] for use in the house. I clean that flue once or twice a year and I'm always suprised how relatively clean it is. I assume this is mostly because of a hot burn.

I've always heard that cresote is worse when burning pine - maybe a hot burn counter acts that :thinker:

Marksr is right, if pine is burned in a hot fire, the creosote issue is negated because the excess resin in pine is burned more thoroughly in the high temps. I personally burn pine in a mix, and the cooler the fire the less pine goes in.

softwoods such as pine have a higher equilibrium moisture content compared to most hardwoods. That means that even if you kiln dry them pine logs will absorb some moisture from the air to reach its equilibrium MC. This is because softwoods are more hygroscopic than hardwoods.

If you use extra BTUs to dry wood, there are less BTUs available to generate sufficient draft or heat the room. Thus, as the draft suffers, you get more condensation. If the Rh% in the flue gases is higher, all the more condensation, which includes creosote.

The sap is moisture and sugar, which is pre-oxygenated hydrocarbon fuel. It will burn must faster than cellulose, which also contains carbon hydrogen and oxygen but it much more complex and takes more BTUs to break down. Want a good firestarter? light a Snicker's bar or potatoe chips. :coffee:

Softwoods have a porous or open cell structure compare to hardwoods. This allows oxygen to diffuse into the cells faster thus speeding up pyrolysis or the gasification of fuel. The wood does not burn directly--it is the combustible gases above it you see burning.

Here is a trick question for you:
On a kiln dried basis, which contains more BTUs--a pound of oak or a pound of pine? :wall:

Hearthman

I am sufficiently dazzled and baffled. Regardless of the science, my experience coincides with Marksr's: Burning pine in a hot fire does not result in noticeably more creosote build-up than burning strictly hardwood.