Woodstove Maintenance

As the hardwoods peak and shower our homestead with a bright blanket of multi-colored leaves, the resulting re-emergence of the surrounding mountains reminds me that cold weather’s coming fast and things here on the ‘stead have to be squared away for that inevitability. First on the list of things to do, of course, is woodstove maintenance.

Our woodstove is a custom job, came with the cabin when we bought the place. It needs to be blackened, as the surface does tend to become a bit pitted and rusty over a period of years. We could use a coat of gun blue, but we usually just get a can of good ol’ stove blacking from the hardware store and apply that. Once it’s on, it needs to be fired up to set, however. And that of course requires cleaning the stovepipe and making sure all the joints are sound (or get replaced, also something that has to happen every few years). And while we’re at that, cleaning out all the packed ashes leftover from springs last cold nights has to be removed, the lining bricks re-set, and all the grates through which the stovepipe passes have to be meticulously cleaned of accumulated cobwebs and possible flammables. A well-maintained woodstove provides reliable and welcome heat for decades whether it’s free-standing or a fireplace insert variety. Without said maintenance it’s a fire hazard for which you may find your insurance lacking.

So now that at least the start on the winter’s wood supply has been cut, split and stacked in a convenient location, here’s the basic overview of “How-To” do whatever else needs doing…

1. Checking the Pipe. The first place to look for needed replacement is at the connection of the pipe to the stove. This joint gets the hottest, and stovepipe is a thin sheet metal rather than a thick cast iron. It will degrade faster than anywhere else. You should of course also check the rest of the pipe joints for rust and thinning, and if anything looks weak go ahead and replace the entire thing. Along with the cap to discourage rain from getting in, and re-tar the flashing where it goes through the roof. Last time we replaced the pipe we got an extra galvanized sheet and wrapped it around the joint section, then fastened it securely with wire. This has allowed the pipe to last longer than it used to, which is cost-effective.

Our stove is in the basement, the pipe goes straight up through the center of the cabin’s living area and right up through the loft and out the roof. This arrangement is very energy efficient, as we get more “living” heat off the pipe than the stove. Being three stories tall, it also minimizes the carbon particulates in wood smoke that makes it all the way out, which is good even though I like the homey smell of wood smoke when coming home from an outing. The downside of the tall pipe is that soot and resin/creosote buildup tends to coat the inside of the pipe quite thickly. This presents a chimney fire hazard, so years that we don’t replace the pipe we have to ‘sweep’ it good.

First thing to do is get a stout stick or paddle and ‘rap’ the pipe starting at its highest point and working your way down to the stove itself. Don’t hit it hard enough to dent it, but do strike all the way around to loosen built-up carbon. You’ll hear it ‘raining’ down as you go, and yes you will have to get it out of the stove once you’re done. But once you’ve ‘banged the pipe’ down its entire length, go on up to the roof and do the interior job. You can purchase a ‘sweep’ (a circular stiff brush), or you can do it the old fashioned way. This involves tying a brick or good-sized stone into an old terrycloth towel and then attaching a rope so this can be lowered into the pipe as far as it will go. If it meets resistance pull it up and drop it down a few times to loosen the blockage. The old towel should be entirely trashed by the time this job is done, so toss it. Then check the sections and joints yet again to ensure that the metal is still entirely sound.

If your woodstove set-up has much shorter sections of pipe with elbows in it, you’ll have to dismantle those elbows and either clean thoroughly with wire brush or replace. These 90º turns pick up a whole lot of carbon and creosote, need extra attention.

If you’ve got one of those pretty fireplace insert stoves, you’ll need to not just clean the pipe but also the chimney. It can be worth it to go ahead and hire a chimney sweep for this purpose, who will also inspect your rock and/or brickwork to ensure the mortar is solid and your rain cap is functional without blocking air flow. A friend’s house very nearly burned down a couple of years ago when his brick chimney caught fire and sent flames and sparks out onto the roof shingles. Don’t let that happen to you, pay attention to your exhaust system!

2. Applying the Blacking. We get ours in a can from the hardware store, which is cheaper and more made-to-order than gun blue. It’s a sort of paint that you apply – just like paint – to the outside wrought iron surface of your stove. You can also apply to the interior, but we’ve never found that necessary.

Once it’s dry you want to open up every window and door throughout the house (so do this on a warm day), maybe crank up those window fans, and build a fire. The blacking doesn’t become ‘one with’ the wrought iron until it’s gotten good and hot. But the process does cause some obnoxious fumes during that setting fire, which is why the house must be open. We have birds, cats and dogs, all of them should be taken to somewhere outside for as long as the setting fire burns, and not brought in again until the fumes have been thoroughly purged by fresh air.

A good blacking job can last for 3 or 4 seasons before needing to be done again, so don’t bother with this unless the metal of your stove is looking rough.

3. Setting the Bricks. This is kind of a dirty job, but well worth the effort if you rely on your woodstove to keep things above freezing on long winter nights or for many hours while you’re away from home. The basic idea is that lining the stove with bricks adds a great deal to its thermal mass, helps it to retain heat even when its vents are shut very nearly all the way off.

We use regular old building bricks. The stove itself is rectangular, so these work very well and tend to stay in place. We set them one-thick to completely cover the bottom of the stove, then 2-high around the back and sides. This means the fire is set right on top of them. On cold nights we load it up with larger pieces of wood, let it catch well, then close down the vents all the way, then a quarter-turn back. Barely enough air to keep it smoldering, not enough for flames. The stove stays warm enough to save pipes, but the house is cold enough to need comforters and quilts on the beds. Who would want to sleep in a hot house in the middle of the winter anyway?

In the morning the vents are opened up a bit and some fresh wood is added, by the time coffee’s ready the stove is cooking away and it’s warm enough for showers and such. Don’t have to actually build any fire at all, as there are enough leftover red-hot coals from the night to fire it up automatically.

If you’re heating already with wood, you probably already know about putting metal or ceramics underneath and on any walls around your unit. These things can get red-hot, and can not only ruin any drywall, wood paneling or wallcoverings in their vicinity, they can also cause them to catch fire. We covered the wall nearest our woodstove with a sheet of that aluminum looks-like-stone skirting for mobile homes, because we happened to have a sheet from a salvage job we did years ago. But just like the brick trick, if you were instead to use stoneware floor tiling or even actual mortared brick, you’d be adding to the thermal mass of your overall heating system. More efficiency the better, and when it’s really, really cold every little bit of radiant heat is welcome.

And whether or not you have small children in the house, do put a ‘fence’ around any woodstove that is taking up room in the main living area. We don’t because ours is in the basement, but where the pipe comes up through the library we have a chickenwire ring-fence around it to keep people and animals away from it. That pipe gets plenty hot enough to burn if touched. We also have a nifty little magnetic temperature gage on the pipe that allows us to tell quickly when the fire’s too hot. Managing the temperature is easy enough to do just by closing the vents a bit, but it can get ahead of you if the stove isn’t right there to be seen and felt.

At any rate, I trust we’ll all have a safe and warm winter on our homesteads. More helpful hints for winterizing the place will be upcoming as the seasons change, so do stay tuned!

Related Ads:

Filed under Biofuels, Energy, Environment, Heating, Homestead, Maintenance, Repair | Comment (0)