Pages Navigation Menu

Serving Woburn, Lexington, Arlington, MA areas

Safety Information

Attention all Woodstove and Fireplace users

If you are one of our many wood-burning customers, you are aware that you have an enemy when it comes to your chimney safety- that enemy is CREOSOTE.  Creosote is a black, tarry or glazed material that can coat every surface inside your flue system that is on the path of your smoke’s exit from the chimney.  Creosote is a carbon residue that accumulates as a by-product of the combustion of wood.  As smoke travels up the chimney, some of it condenses and turns to soot and creosote.  It is especially prone to building up at chimney “cool” spots (such as the smoke chamber of the fireplace, or the very top of your flue), and at bends in the flue.  Creosote is your enemy because it is flammable- it can ignite inside your flue system and become fuel for a chimney fire.

The most important way to avoid creosote build-up is to have your chimney cleaned regularly.  For most woodstove burners, that means every year, or after 2 cords of wood.  For standard fireplace users, once every 3 years is usually right, because the average FP customer takes that long to burn 2 cords.  However, please read about ACS (below).  We cannot remove the most-hardened creosote deposits using regular sweeping methods.  ACS can help.

For many customers, regular cleanings are all that is necessary to keep creosote levels to a minimum.  Additionally, all wood-burners should observe the following rules:

  • Burn clean, seasoned hardwoods (avoid pine).
  • Don’t burn trash, paper, or newspaper (a piece or two to get started is OK)
  • Place a woodstove thermometer on your stove.  Check it often.
  • Don’t run your stove too low.  Burning at 200 degrees saves on wood, but causes excessive creosote build-up.
  • Don’t run your stove too high.  Over-firing can damage your stove and may start a chimney fire.
  • Don’t put a large stove in a small room.  You will be tempted to run it too low.
  • A good temperature is 400-500 degrees.
  • When you start your fire, let the chimney warm up gradually.  Shocking it can crack the inner brickwork or clay liner.
  • Have a plan for a chimney fire- keep a fire extinguisher ready.
  • Use ACS – Anti-Creosote Spray! We cannot overstate the value of this helpful maintenance product.  Simply spray on the burning logs.  About 10-15 pumps per day will work, but you can double that for stubborn creosote problems.  The agents  in the liquid react at 300 degrees, and attack the tarry creosote, which is transformed into a dry, crunchy, and less flammable substance.  The new substance is much easier for us to loosen and remove during normal chimney sweeping operations.   ACS should be kept away from kids and pets and will stain fabrics, so be careful.  ACS can be purchased at some hardware stores.  Alternatively, we are glad to deliver it to your door for $15 per bottle.  We suggest that you use 1 bottle per 1 cord of wood burned.

The Best Way to Upgrade your Woodstove Safety

  • We strongly suggest that all our wood-burning stove customers consider having us upgrade the installation of their stove.  Many of you had your stove installed 10,15 or even 20 years ago.  Installation codes and techniques have advanced every year since.
  • Simply put, we suggest the installation of a direct-connect stainless steel chimney liner with hook-up to the smoke outlet of your woodstove.  The advantages of this system are many:
  • Smoke is contained inside an extremely strong and durable sleeve and is carried directly to the top of the chimney.
  • The new liner is a consistent size and shape.  This eliminates cool-down spots (such as your smoke chamber spill area) and by-passes any unseen cracks / flaws in your existing flue.
  • Flue temperatures are kept more consistent, lessening the build-up of creosote.
  • Draft is usually improved.
  • Annual cleanings are more thorough – there are no unreachable crevices that creosote can collect in.
  • Finally, if a chimney fire were to start inside your chimney, it would be contained, and would likely burn itself out.  In an un-lined or even clay-lined flue, chimney fires often damage the chimney’s inner walls; in a worst case, those cracks allow heat and flame to spread to the wood framing surrounding your chimney.  A home fire could result.

TESTIMONY:  The author (Joe) has a large wood-burning stove, through which 4 cords of wood are burned each year.  Along with use of Anti Creosote Spray, and a cleaning each spring, I elected to lined my woodstove’s flue with a stainless steel liner, though I already had a clay liner inside the chimney.

I can sincerely say that it was well worth my time and expense.  The benefit to me was the knowledge of a job well done with no safety compromise, increased performance, ease of cleaning, and the peace of mind that allows me to load up my stove, set the damper, and leave the house for the day with no worries.

Please talk to us if you would like to upgrade.