Heating with wood has been a “necessary” tradition for thousands of years, but with the advent of the industrial revolution, and the advancement in methods of heating homes and buildings, heating with wood became less and less popular. During the 1970s Energy Crises, there was interest in seeking “alternative” energy sources, and people started to rediscover the benefits of heating with wood. In the early 1990s, gas stoves and inserts took the place of traditional wood burning. People were just too busy to deal with the time and energy required with wood. In the last few years however, wood has come full circle, yet again. It’s funny how people go back to things that are simple, reliable, and secure, in times of uncertainty.
I am a former Technical Administrator for a Wood and Gas Stove manufacturer, and thought I might be of some help by passing on some of my experience and knowledge. Basically, I was the guy who trained “the stove professionals” at the places that customers buy their stoves.
Heating your home/retreat with wood can be very rewarding, especially in a SHTF [1] scenario. It can literally mean the difference between barely surviving, and comfortably thriving. If a wood stove is not installed, operated, and maintained properly, there is a very real possibility that there can be substantial loss of property, and or life.
Fireplaces
While fireplaces do add warmth and comfort, they are far from being efficient. Most fireplaces are only about 10% efficient, in other words, 90% of your fuels’ BTUs [2] are going straight up the chimney. If you do have a fireplace in your home, and would like to make far less trips to the wood pile, please consider installing a wood burning fireplace insert.
Selection of a wood burning stove
There are many types of woodstoves, and not all woodstoves are built alike, and there are a few features that are highly advantageous. Most stoves will burn wood effectively, that is, yes the wood does burn, but there is a bit more to it than that.
Catalytic Stoves – The king of wood stoves
A catalytic stove utilizes what is called a “Catalytic Combustor”. This combustor is similar to the catalytic combustor (converter) in a cars exhaust system. Its’ size can differ, but usually is 7” round, 7 x 9 oval, or rectangular, and about 2” thick. The combustor is a ceramic or stainless steel honeycomb on which is coated a catalyst. The catalyst may be a combination of one or more precious metals, including the following: platinum, palladium, rhodium and cerium. The catalyst chemically lowers the combustion temperature of the smoke from a wood fire, thereby allowing more smoke to burn, resulting in higher efficiency, and less creosote buildup. The active operating range is approximately 700-to-1,400 deg. F. The unit will glow red around 1,000+ deg., but is operating properly as long as it is in the active range. Catalytic Stoves come with a “Cat Thermometer” When operating properly; all that should be exiting the chimney is a white, steamy plume.
Pros
Saves Time and money
Dramatically longer burn times. Up to 40 hours on low setting (Blaze King Brand)
Much higher efficiency
Fewer trips to the wood pile
Chimney stays much cleaner, less chance of chimney fire
Greater burn control, resulting in more even temperatures in the home/retreat
Uses less woods
Cons
More expensive than traditional non-cats
Average life of converter is 5-9 yrs, depending on use and type of fuel burned
Replacement Cat’s are expensive. (This cost is made up by time and money saved)
Note: In worst case scenario (i.e. TEOTWAWKI [3]) and the cat is no longer working, the by-pass door (not the loading door) can be left open and the stove will still operate. The EPA [4] will say that it is illegal to operate the stove without the use of a properly operating catalytic combustor. If it is TEOWAWKI, I’m sure you will get a pass on this.
Non-Catalytic Stoves
Non-cats are more commonplace, yet they too, are not all the same. You have your basic type, that is, a box with a hole in the top, and you have others that employ what is called “secondary air”. Secondary air aids in better combustion of smoke, resulting in lower emissions.
Pros
Less expensive than Catalytic
Fewer parts to wear out
Cons
Shorter burn times (cold mornings?)
Less efficient
Uses more wood
More trips to the wood box
Thermostats
Woodstoves with thermostats are much better at controlling the burn, and maintaining a more even temperature in the house. They are incorporated into the stove itself. (Not on the wall) A thermostat is comprised of a “flapper” that is controlled by a wound, bi-metal strip. As the stove gets hotter, the flapper will start to close, thus controlling the amount of fresh air given to the fire, and conversely, will open up as the fire dies down.
A stove without a thermostat will generally have a manual air intake control, in the form of a plate that you can move to control the volume of air coming into the firebox.
Positioning of stove in the house
It is generally best to place your stove in a centralized area in the home. Natural air flow is a large consideration. Most average sized homes can be heated sufficiently with a quality woodstove, based upon layout and natural air flow. It is preferred to have the chimney within the envelope of the home and not routed on an outside wall.
Pre-Manufactured Chimney Systems
Most installations will utilize a pre-manufactured chimney system. It is important to understand that there is two different systems, one is standard residential, and the other is High Temperature Mobile Home/Alcove/Close Clearance. Normally, single wall pipe called a connector, is used to come off of the stove. This pipe must be 24/26 MSG Black/Blued steel stove pipe. (Do not use aluminum or galvanized pipe) Once reaching the ceiling, it will transition into a “ceiling box” that has Triple Wall (actual chimney), that runs the rest of the way.
Always follow the manufacturer’s installation requirements, and local codes. DO NOT MIX DIFFERENT CHIMNEY SYSTEM.
Never use more than a total of two 90 deg. turns in an installation. Any more than that, will significantly reduce your draft. If possible, use two 45’s instead of a 90. Furthermore, never slap a 90 deg. elbow right off of the top of a stove. Preferably, you would go a minimum of 36” up, before turning. Furthermore, if a horizontal run is needed, it should be 36” or less, AND have a slope of ¼” per ft., downward into stove. It is important and required, that the chimney extends a minimum of 3 ft. above a roof, and is at least 2 ft. higher than any area of the roof within 10 ft.
Note: Chimney sections should ALWAYS funnel into the stove collar, meaning the crimped end faces down into the stove. This allows for condensation/creosote to drain into the stove, and not leak outside of the pipe
Masonry Chimneys
If you have an existing masonry chimney, and are able to route your stove pipe into it, you can save a lot of money. A masonry chimney must be lined; the liner is usually made out of clay 5/8” thick min., and appropriate cement. A chimney liner should never be smaller than the cross sectional area of the stove collar, example: An 8” collar is approx. 50 square inches. A visual inspection of the chimney is needed prior to the installation of the stove. Look for cracks/holes, loose field stones/bricks, and mortar that is crumbling/deteriorating. Creosote patches are signs of fresh air being introduced through these cracks. Have a professional chimney sweep inspect and repair the chimney if you feel that this is beyond your capabilities/judgment. Overly large, unlined, existing chimneys often will not draft properly, will accelerate the buildup of creosote, and usually violate code and installation requirements. All installations require a thimble when the pipe enters the chimney through a combustible wall. It may be constructed of brick, or pre-manufactured.
Note: Make sure the ash clean out door on the outside base (if installed) of the chimney is closed. This will keep cold air from being introduced into the chimney, and reducing draft.
Creosote and chimney cleaning
Creosote is basically caused by smoke cooling and condensing on the chimney walls. It can be built up with the addition of ash and other large, unburned carbon particles. It can present itself as hard and shiny, or thick, light and fluffy. You should inspect your chimney and connector system twice a month during burn season. Pay close attention to the appearance of creosote patches inside of the chimney. The existence of these patches is an indication of fresh air leaking into the chimney, and should be repaired or replaced immediately.
Use only a tight fitting chimney brush to clean your chimney. Getting “Bubba” up on top of the roof with tire chains, hoses, and the pool skimmer, will not only result in unsatisfactory results, it can potentially damage your chimney. Remove the first section of pipe off the stove, and attach a plastic bag to the open end of the pipe. Again, follow manufactures cleaning instructions, if available. You cannot expect to get every speck of creosote cleaned off, so don’t lose any sleep over it. Just do your best to brush as much of it out as you can.
WARNING: NEVER INTENTIONALLY START A CHIMNEY FIRE TO CLEAN OUT THE CHIMNEY
“Magic” Chimney Creosote Cleaning Logs/Products
My experience has shown that nothing can substitute a tight fitting chimney brush for cleaning a chimney. While there are several products out there that claim to “clean” or otherwise break down the buildup of creosote, I would not recommend them.
Safe Operation of Stoves
Always follow the manufactures operating instructions, and procedures. If none are available, please consider the following:
Never leave the stove unattended with the loading door left open. Leaving the loading door open, then getting distracted by a phone call, or knock at the door, can have disastrous results. Once a loading door is opened, there is virtually an unlimited supply of combustion air available for the fuel. If left unchecked, especially if the stove has just been filled, the stove can reach temperatures exceeding that in which the stove is designed. This can warp the stove, or worse, cause a house or chimney fire.
Never use gasoline, kerosene, lighter fluid or any other type of accelerant, to start a fire, or to “freshen up” a fire.
Never mix, or substitute chimney brands/systems. If you are trying to save money by mixing and matching stove pipe, you stand the chance of losing so much more. Chimney Systems are just that, “systems”. They have gone through extensive testing for a reason, to save lives and property. Many have gambled and lost on this issue. Do not use aluminum or galvanized “duct” piping, they cannot withstand the high temperatures of burning solid fuels.
Use only solid, seasoned wood as fuel, unless the stove has otherwise been designed for such fuel. Do not burn coal, oil, plastics, wrapping paper, charcoal, railroad ties, particle board, and sawdust, painted wood, or anything else that is not dry, seasoned wood. Using unseasoned “green” wood will increase production of creosote, and make for poor draft up the chimney. Seasoned wood is wood that has been cut and allowed to “season”, or sit, for a period of usually at least 8 months. Saltwater driftwood can be death for a stove; it will [cause rust that will] eat right through it
If you are experiencing a chimney fire and it is safe to do so, then make sure the loading door is closed, turn down the thermostat all the way (or manual air control), evacuate your home, and call 911.
Check Loading Door Gasket twice during each burn season. You can do this by opening the door and positioning a dollar bill on the area where the door gasket meets the opening on the stove, now close and latch the door. There should be noticeable resistance when pulling the bill out. Try this in different areas around the door.
Ensure proper combustible clearances to the stove are maintained. Refer to your owner’s manual on distances. If your stove is bought second hand, and does not have the clearances and certification agency labeled on the unit itself, contact the local authority having jurisdiction, to verify code requirements.
I have gone through most of the basics regarding wood burning stoves, and I’m sure that I’ve missed a thing or two. What I have presented are just general guidelines. I cannot emphasize enough that you follow the manufacturer’s Installation and Operating Instructions, doing so will ensure best performance, with the lowest risk of danger. – Kevin K.