How to Maintain a Tiny Wood Stove
Proper maintenance is critical to the efficient function and safety of your wood stove.
Before Each Use
Use a brush to collect ash in the ash pan, and empty it prior to each fire, and as needed. Ashes may contain embers for hours or days after the fire goes out, so they’re best disposed of in a fireproof ash bin. Improper disposal of ashes (i.e. tossing them in the kitchen trash can or vacuuming them with a household vacuum) is a leading cause of stove-related house fires, so treat ashes with appropriate care.
Some soot will accumulate on your stove glass. To remove it prior to starting your stove, moisten a crumpled sheet of newspaper with water and dip it in some wood ash, then use the ash to scrub the glass until the deposits are removed. There are commercially available wood stove glass cleaning products, but scrubbing the glass with wet newspaper and wood ash seems to work the best.
Keeping the Flue Clean
The most important ongoing maintenance task for your wood stove is to keep the flue system clean. As you use your stove, some smoke will condense inside the flue system and form creosote, a flammable tar-like substance. Too much creosote buildup can increase your risk of a chimney fire.
Some creosote formation is inevitable, so regular sweeping is necessary. But there are several things you can do to minimize the buildup.
Burning properly cured hardwood fuel will help your fires burn cleanly, which will minimize creosote buildup. Moisture content in solid fuels consumes a significant amount of heat and results in cooler fires and lower flue temperatures. The colder the flue temperatures, the more creosote will condense inside the flue.
Fuels like kiln dried hardwood and pressed logs (except the ones that contain wax) are relatively expensive fuel sources, but are ideal low-moisture fuels for your wood stove. If you plan to burn low and slow overnight, using a more expensive low-moisture fuel during that time can help reduce creosote buildup.
Bulk cordwood is a good fuel option if you have the space to allow it to cure properly. Most firewood dealers deliver wood before it is completely cured, so you should plan on ordering a supply at least a year before you need it. If in doubt, using a firewood moisture meter is the best way to ensure your fuel is properly cured.
Softwood has a lower BTU content than hardwood, but it can still be burned cleanly as long as you keep your flue gases up to temperature.
Pitchy, resinous pines and "fatwood" make great firestarters, but can cause excessive creosote deposits if burned in bulk. Avoid using resinous wood as bulk firewood if possible, and inspect and sweep your chimney more often when resinous wood can't be avoided.
Creosote consists of flammable compounds escape your stove without being fully burned, and then cool and condense in your stovepipe. Ensure that you are burning your fuel as completely as possible to minimize the amount of flammable compounds that end up in your chimney.
Avoid smoldering or "choking" your fire by keeping the air controls relatively open, and making gradual changes as you adjust your burn rate. Whenever possible, reduce the stove's primary air (bottom of the firebox) first, and feed your fire primarily with secondary air (top of the firebox). The secondary air mixes extra oxygen with any unburned flue gases while they're still in the firebox, which can allow the gases to burn more completely before exiting the stove.
Regardless of your fuel source, a stovepipe thermometer is a critical tool for monitoring your stove's performance. Keep the flue temperatures in the "ideal" range to help prevent creosote from forming in your flue system.
If you're burning low and slow fires, you'll likely get some extra creosote buildup overnight. You can help remove some of that buildup by getting your flue system nice and hot in the morning. People call this "burning off" the creosote, which is a misnomer. The goal is not to actually burn the creosote, but just to heat it up. Getting the flue hot enough will help to gas off some of the sticky volatile compounds in the creosote, which both reduces the volume of the creosote and makes it less sticky, so deposits collect less readily.
Inspecting the Flue System
You will need to inspect your flue system on a regular basis and clean it as often as necessary. The frequency of cleaning will depend on how you use the stove—how often you use it, what type of fuel you use, and what temperatures it runs. It’s a good idea to inspect a new installation weekly for the first month, then on a monthly basis during the heating season (cleaning as needed). If you experience deteriorating performance or puffs of smoke entering the room when opening the door, inspect the flue. If there is ⅛” or more of build-up on the wall of the flue, clean it before using the stove again.
Sweeping the Flue System
To clean the flue, use a chimney brush that will fit the diameter of your pipe. This brushes of this rotary chimney cleaning kit attaches to your cordless drill, and can be trimmed to fit 3", 4", and 5" flue sizes.
Brush the interior of the pipe until buildup is removed. If there is excessive sticky creosote buildup, using a commercially available creosote remover prior to sweeping the flue can help to loosen the deposits, but is not a substitute for mechanical sweeping.
Avoid breathing creosote dust, and wear a NIOSH approved respirator if your sweeping method releases dust into the air.
If possible, sweeping from the top of the chimney can significantly reduce the dust and mess created by sweeping. Remove the baffle from your stove, shut the door, and close the air controls. Remove your chimney cap and sweep your chimney from the top. Clean the debris out of your stove (or rear exit tee) once the dust has settled.
Maintaining Your Stove's Finish
Most stoves are painted with high temperature paint, which can scratch with use. I periodically wipe my stove top down with a thin layer of cooking oil to cure any bare metal and prevent rust, same as you would with a cast iron skillet. Cooking oil can smoke when curing, so be sure to have the space well ventilated during the next fire. I like the look of a worn in stove, but if you ever want your stove to look brand new again, you can repaint it with Stove Bright brand high-temperature paint.
Another useful product to maintain the finish of a wood stove is stove polish. If your stove is rusty, rubbing it with stove polish can simultaneously remove rust and add a layer of protection, while providing a shiny black finish.
If your stove uses firebrick in the firebox, bricks will last for years of typical use, but will eventually need to be repaired or replaced. Chips and cracks can be repaired by filling cracked joints with stove cement.
You can find correct replacement bricks for Dwarf stoves here. For other stoves, contact your stove manufacturer to source correct replacement bricks.
Airtight stoves use gaskets on their doors, which need to be checked and replaced from time to time. To inspect the gasket while the stove is cold, place a dollar bill halfway in the door opening and close and latch the door. If you’re able to pull the bill out from between the door and the stove with no resistance, the gasket is worn and should be replaced.
You can find complete replacement door gasket kits for Dwarf stoves here.
If a stove gasket is still in good condition but starts to detach, it can sometimes be reattached to the stove with stove gasket cement. Clean off as much of the old gasket cement as possible from both surfaces. Then, dampen the area with water and apply a thin layer of cement to the gasket channel. Press the gasket firmly into the cement, being sure to keep the gasket material in a relaxed state, avoiding stretching it at the corners. Close the door to ensure the gasket is set in place, then allow to air dry for 1 hour with the door open. Fire the stove within 30 days and heat to 500 degrees F to cure the cement.