4 Tips to Help Your Furnace Work BetterMarch 18, 2019
For the furnace to work properly and for a long time with maximum efficiency and to avoid its premature destruction, the owner of the furnace should carefully study the operating rules. This manual will contribute to your furnace work to be on the top. Before usage, the furnace must be dried. To do this, initially, the furnace is heated twice a day, for 1-1.5 hours with a small amount of fuel (no more than 2 kg with a humidity of no more than 15%) with the blower and furnace door open. Do not use wood chips, chipboard in large quantities. For a short time, they will give a high temperature, which will lead to the cracking of the furnace. So the furnace is heated until the defogging of the outer walls stops and water droplets appear on the valve. This rule helps to your furnace work to be quite qualified.
1. Scheme of the kindling and furnace
After that, the furnace is dried, burning an increasing amount of fuel, with the furnace closed. During the entire period of drying, the chimney and the blower are not closed, and the room is ventilated vigorously. Depending on the size of the oven, its drying lasts 10-20 days in the summer and 3-4 weeks in the fall and winter.
2. High-speed drying causes cracks in the masonry and can disable the furnace before it starts operating
For the troubleshoot furnace, it is filled with a full amount of fuel and burned for 1.5 … 2.5 hours, that is, until the furnace walls are heated to the limit. Lack of smoke will indicate the presence of traction; touching the surface with your hand, you can determine the degree of heating in different places.
Before you start your furnace work, the furnaces should be checked and regularly maintained. Particular attention should be paid to the integrity of the masonry, starting from the first row to the top of the pipe. There are not rare cases when the force of frost heave breaks the furnace and especially the pipe (the pipe in the attic must be whitewashed so that cracks can be seen). Check furnace devices and the state of the firebox, both before the start of the heating season and during operation.
Eliminate cracks in the masonry (fill with mortar, or change burst bricks) and seal up the gaps between the masonry and stove devices (you can use kaolin wool soaked in clay mortar). This will significantly improve the operation of the furnace, increase efficiency and increase fire safety. The furnace must be manufactured in accordance with the established rules of fire safety in the Russian Federation and GOST 9817-82 “Solid fuel household appliances”.
The process of fuel combustion is divided into three periods: burning, intense burning and burning out. In each period, a different amount of air is required to burn the fuel completely.
The largest amount of air for fuel combustion is required in the intensive burning stage. Firewood is known to contain solid and volatile combustible substances. Only 1 kg of wood needs 3.8 m3 of air. This is the optimal theoretical value. In practice, air flow reaches 6-9 m3 per 1 kg of wood. In this case, the excess air is 1.6-2.4 times.
If you want your furnace work properly, it should be noted that less air is required at the stage of burning and burning out. If you give the same amount of air 6-9 m3 per 1 kg of firewood, for the entire combustion reaction time, heat loss from underburning will be 3-5%, and afterburning of fuel in the stage of burning will be 20-35%. However, if air is supplied to the furnace in quantity less than optimal, chemical underburning of the fuel occurs.
As a result, the energy contained in the fuel is not completely released, and volatile substances not burned down are deposited in the form of soot on the walls of the furnace. Soot has a low thermal conductivity and therefore deposits of soot on the walls of the furnace reduce the useful heat transfer from the furnaces. In addition, soot deposits reduce chimney sections, reduce cravings and create a fire hazard, as soot is combustible.
3. At the stage of ignition and intense burning, the temperature in the furnace rises, at the stage of combustion it decreases.
It follows from the above that in the stage of intense burning the blowing door must be opened so that the optimal amount of air falls into the furnace in order to make the furnace work properly. This can be judged by the color of the flame. It should be light yellow. If the flame is dark yellow with black smoke, little air enters the firebox, the combustion reaction takes place with low efficiency and high soot deposition on the furnace walls. This leads to clogging of the furnace, reducing its heat transfer and increased flammability.
Therefore, in this stage, it is strictly forbidden to heat the furnace in the mode of glowing burning with the blower door closed. A bright white flame indicates excess air. This is also indicated by the strong humming of the furnace. In this case, it is necessary to cover the glowing door. In the afterburning stage, when coals remain in the furnace, the blowing door can be completely covered. It does not make sense to regulate the burning process with the furnace valve, although at the stage of burning it should be covered to reduce the draft of the pipe.
For ignition, it is desirable to use paper, bark, resin torches. This will remove cold air from the chimney, create cravings and provide an ignition temperature of wood 300-350 ° C. In the cold season if the oven has not been used for a long time, it is better to start kindling with the open valve of the summer course.
4. After ignition, dry logs should be put in the furnace to obtain a working temperature of 800-900 ° C
Firewood should be dried for 1-2 years, and have a maximum humidity of 15%. When using raw wood, the loss of heat of combustion can reach, according to Finnish sources, 34-57%. It also leads to rapid clogging of the furnace and increased fire hazard due to the rapid clogging with soot. Part of the heat generated during the combustion of fuel is spent on the evaporation of water contained in it.
The heat spent on the evaporation of water is lost with the steam exiting the tube. It is desirable to have wood of approximately the same thickness (5-10 cm) and humidity so that they burn with the same gap in time. Otherwise, it happens that not burned single heads take more heat than they give, because you can’t close the pipe until they burn completely. This also applies to fireplaces, and without it, your furnace will not work.
For making your furnace work for a long time and not to require cleaning, do not burn garbage in it, especially polymers, rotten and wet wood, varnished, painted wood, paper, and cardboard.
Otherwise, it will need to repair or replace with a new one.
The substances that arise during the burning of these materials are deposited on the walls of the stove (fireplace) and repeatedly increase the risk of fire and litter the environment. We had repeatedly encountered cases when, after a month of operation, the furnace stopped working. At the opening of the furnace, it was found that the 13 cm wide cap was completely clogged with soot adhering to the walls. In this case, it is necessary to alternately clean the walls of the caps from soot, and then burn the caps with dry fine aspen wood, starting from the top. This guide will make your furnace work much better.