HOW TO OPERATE AN EFFICIENT WOOD BURNING STOVE ( SUPPLEMENT 3 ) STOVE BUILT IN USA USING REFERENCE DOCUMENT REFERENCE: HOW TO BUILD AN EFFICIENT WOOD BURNING STOVE REVISION (A) 07/16/2013 ED KEANE 08/09/2013
Introduction This supplement (3) is educational information for the stove installers to pass on to the women who will be the primary user of the efficient wood burning stove. It requires a new method of cooking which will be a negative because it requires more work preparing wood and feeding the stove as you cook, however the benefits are many. The benefits are a healthy environment for the family, less burns and less time foraging for wood. The work and time added will be offset by the stove efficiency requiring less wood. I can understand that the woman who cooks wants to do what she is doing and her mother did before her. If I could design a stove that would fit her life style that would be the best scenario but studies show that is not possible. To burn wood efficiently there is a need for a rocket elbow. To remove the toxic smoke from the home I need a smoke path and a chimney. The stove needs to be raised to protect the children from serious burns. To obtain these benefits the woman who cooks needs to understand the importance of efficient wood burning stoves and how they work. The installer needs to understand these instructions so he could educate the new stove owner on how to use the stove. The main objective using an efficient wood burning stove is to use the minimum amount of wood to cook a meal. The women who cook everyday will be the ones who make it work but they need the basics first and then they can form groups and be the educators. Preparing Wood First we need to cut the wood to the proper length about 40 cm long. In the USA we use a bow saw and a sawbuck see Figure 1. Whatever method you use, make it ease so it will become a normal routine. Splitting Wood If the wood pieces are larger than about 5cm diameter they should be split. When you split wood you create more exposed area and it burns better. To split wood you will need to place the log on a hard surface. You will need a steel wedge and a sledgehammer or an axe see Figure 2. Figure 3 shows wood that has been cut and split and is ready to be stacked for drying prior to use. ED KEANE 08/09/2013 Page 1
Drying Wood H0W TO OPERATE AN EFFICIENT WOOD BURNING STOVE The moisture content of fresh cut wood is high. This wood will result in a smoky fire that will not burn efficiently, the wood needs to be dry. To dry the cut and split wood, stack it in a sunny spot for at least three months before using. In the rainy season the wood needs to store in in the home. Feeding the Stove Figure 4 is a view at the centerline of the stove that shows how to feed the wood into the combustion chamber. Only the tips of the wood burn and as tips burn off the wood pieces need to be pushed gradually into the combustion chamber (CC). Therefore the cook needs to attend the stove while the food is cooking. If the food is cooking to fast wait before adding more wood. If and the wood has been pushed into the combustion chamber a brick can be used to cover the CC opening while the food shimmers see Figure 5. If the cooking slows down remove the brick and add more wood and repeat the process. See Figures 6 and 7 for pictures that demonstrate the process. Note; If there is excess oxygen wood will burn too quickly and the food will cook too fast. Wood burning too fast can be the result of too much draft and there is no damper in the chimney to regulate the draft. A brick covering the CC inlet will help slow down the air intake to the combustion chamber which will act as a damper. Cleaning the Chimney There is little information in the reference document on how to fabricate and build a chimney that removes the smoke from the home. The chimney needs to be fabricated in sections so it can be disassembled. Figure 9 shows a young girl cleaning a stove pipe section with a broom made with stiff straws fastened to a long handle. This is necessary to prevent buildup of creosote in the stove pipe that can cause a fire. This is a real maintenance item and may be alien to the user of the new efficient wood burning stove. Here again education will be important to the operation and maintenance of an efficient wood burning stoves. This item is important and more attention needs to be given to the ED KEANE 08/09/2013 Page 2
details for disassembly of the stove pipe. There may be a need for a special group who will be responsible for fabricating the stove pipe and will perform maintenance and cleaning of the stove pipe where the new stoves are installed. Problems Figure 8 shows some problems with some of the early stoves installed in Sumbawanga. This is not to be critical, they are important lesson learned and they can be rectified. They demonstrate the need for education and it is not easily solved. The women who cook have been using three stone fires their hold life and now they need to change and change is never easy. The women are an import part of any stove project and they need to be involved and understand what we are trying to accomplish. Instructions for Safe Cooking Herein page 11, are instructions for safe operation of the new efficient wood burning stove. However a lot more information and education is required for the women who cook and operate the new stoves. The more they know about the stove and its benefits they can accept the new life style associated with cooking on a new efficient wood burning stove. ED KEANE 08/09/2013 Page 3
FIGURE 1 CUTTING FIRE WOOD TO LENGTH IN THE USA This is just an example, to use this method you would need a bow saw and a sawbuck (wood support that can easily be built). However you accomplish this task make it ease so it will become a normal routine. ED KEANE 08/09/2013 Page 4
FIGURE 2 SPLITTING FIRE WOOD FIGURE 3 SPLIT WOOD READY TO STORE ED KEANE 08/09/2013 Page 5
COOKING PLATE SMOKE BY HAND PUSH WOOD TO FIR WOOD FEED WOOD INTO THE COMBUSTION CHAMBER FIGURE 4 SECTION AT CENTERLINE OF STOVE Section view shows method of feeding fire wood into combustion chamber. A longer piece of wood is used for pushing. The object is to burn the tips of the wood until it is consumed and push in the remaining section of wood. ED KEANE 08/09/2013 Page 6
LOOSE BRICK TO REDUCE AIR INPUT INTO FIRE COOKING PLATE SMOKE STEEL WOOD RACK FIRE FIGURE 5 -SECTION AT CENTERLINE OF STOVE WITH BRICK INSTALLED TO REDUCE AIR INPUT Once the fire wood has been pushed into the combustion chamber the input air can be reduced to slow down the cooking and save wood and prevent fast burn that can damage the stove (combustion chamber, cooking plate and chimney). If the cooking slows down remove brick and add more wood and repeat process. ED KEANE 08/09/2013 Page 7
A LONG PIECE OF WOOD TO PUSH SHORTER PIECES INTO CC FIGURE 6 PICTURE AT FACE AT CC INLET SHOWING WOOD BEING PUSHED INTO THE CC LOOSE BRICK TO REDUCE AIR INPUT INTO COMBUSTION FIGURE 7 -STOVE PICTURE SHOWING A METHOD OF REDUCING AIR INPUT USING A BRICK TO ACT AS A DAMPER ED KEANE 08/09/2013 Page 8
Problem H0W TO OPERATE AN EFFICIENT WOOD BURNING STOVE FIGURE 8 EXAMPLE OF A PROBLEM First the wood needs to be cut in smaller pieces and feed into the stove during cooking. The black soot on the face of the stove housing indicates the wood was burning outside the combustion chamber (CC). The stove housing at the CC inlet is eroded from fast burns due to a high draft from the chimney. This stove with fast burn will eventually damage the stove housing, which is already happening it can warp the cooking plate and reduce the life of the chimney. Therefore the instructions herein need to be followed. It s good we built prototype stoves and learned that these things can happen. ED KEANE 08/09/2013 Page 9
(This should be done outside the home because it is a dirty job) FIGURE 9 A YOUNG GIRL CLEANING A STOVE PIPE ED KEANE 08/09/2013 Page 10
INSTRUCTIONS FOR SAFE COOKING 1. DO NOT BURN PAPER, LEAVES, TRASH, PLASTICS OR GARBAGE USE ONLY WOOD.- 2. BURN ONLY SEASONED WOOD THAT IS DRIED FOR A LONG TIME.-THIS IS NECESSARY TO PREVENT CREOSOTE AND TAR BUILDUP IN STOVE PIPE THAT CAN CAUSE FIRES.- 3. USE THE FOLLOWING MAXIMUM WOOD SIZE, LENGTH- ABOUT 50 CM WITH CROSS SECTIONAL SIZE WIDTH 5CM- HEIGHT 5 CM- PREPARE WOOD FOR COOKING BY SPLITTING AND CUTTING TO LENGTH- 4. FEED WOOD ON STEEL RACK INTO COMBUSTION CHAMBER USING A PIECE OF WOOD- IDEALLY ONLY THE TIPS OF WOOD SHOULD BE BURNING AND THE FIRE SHOULD BE DIRECTLY UNDER THE POT. THERE SHOULD BE NO FIRE, EXCEPT IN THE COMBUSTION CHAMBER- 5. REMOVE ALL ASHES FROM THE COMBUSTION CHAMBER BEFORE STARTING A NEW FIRE AND WHILE OPERATING THE STOVE, IF THE ASHES FILL UP ABOVE THE TOP OF THE WOOD TRAY.- 6. START FIRES WITH A BUNCH OF VERY THIN STICKS OF WOOD WITH A FIRE AT ONE END, PLACE THE LIT END INTO THE COMBUSTION CHAMBER ABOVE WOOD TRY, THEN ADD LARGER PIECES AND SLIDE THEM ALL THE WAY INTO THE COMBUSTION CHAMBER-THIS IS AN IMPORTANT TECHNIQUE TO DEVELOP THAT WILL MINIMIZE SMOKE DURING STARTUP.- 7. WRAP A SCREEN AROUND STOVE PIPE IN AREAS THAT CAN BE REACHED BY CHILDREN TO PREVENT THEM FROM TOUCHING THE STOVE PIPE AN RECEIVING BAD BURNS, -THE STOVE PIPE AND THE STEEL COOKING PLATE TEMPERATURE DURING OPERATION IS ABOUT 230 DEGREES CENTER GRADE. THAT IS OVER TWICE THE TEMPERATURE OF BOILING WATER ED KEANE 08/09/2013 Page 11